MANUAL FOR STATISTICS ON ENERGY
CONSUMPTION IN HOUSEHOLDS
-MESH PROJECT-
Report 7: Operational list of
variables/concepts and their definitions
September 2012
2012
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
Index
1.
INTRODUCTION ............................................................................................... 8
2.
HOUSING STOCK CHARACTERISTICS ......................................................... 10
2.1.
DWELLING .................................................................................................. 10
2.2.
OWNED/RENTED ....................................................................................... 10
2.3.
DWELLING TYPE: ........................................................................................ 10
2.3.1.
Single House .................................................................................................................................... 10
2.3.2.
Apartment ....................................................................................................................................... 11
2.4.
URBAN/RURAL ........................................................................................... 11
2.5.
HEATED FLOOR SPACE ............................................................................. 11
2.6.
AIR-CONDITIONED FLOOR SPACE .......................................................... 12
2.7.
BUILDING ENVELOPE................................................................................. 12
2.8.
COMMUNAL AREAS OF THE BUILDING................................................... 12
2.9.
DWELLINGS BY PERIOD OF CONSTRUCTION ......................................... 12
2.10.
3.
AVAILABILITY OF INSULATION ............................................................... 13
HOUSEHOLD CHARACTERISTICS ................................................................. 14
3.1.
HOUSEHOLD .............................................................................................. 14
3.2.
NUMBER OF OCCUPANTS OF A DWELLING........................................... 14
3.3.
HOUSEHOLD INCOME .............................................................................. 14
3.4.
ECONOMIC ACTIVITY ............................................................................... 15
3.5.
PRIMARY RESIDENCE ................................................................................ 15
3.6.
SECONDARY HOMES ................................................................................ 15
4.
CONSUMPTION/EXPENDITURE OF ENERGY COMMODITIES .................... 16
4.1.
CONSUMPTION ......................................................................................... 16
4.2.
EXPENDITURE .............................................................................................. 16
4.3.
ENERGY COMMODITIES ........................................................................... 17
4.3.1.
Electricity and Heat........................................................................................................................ 17
3
4.3.2.
Natural Gas...................................................................................................................................... 17
4.3.3.
Oil ...................................................................................................................................................... 18
4.3.4.
Solid Fuels and Manufactured Gases ......................................................................................... 20
4.3.5.
Renewable Energy and Energy from Waste ............................................................................. 22
4.4.
UNITS
OF MEASUREMENT
OF
ENERGY
COMMODITIES IN
THE
RESIDENTIAL SECTOR AND CONVERSION EQUIVALENTS ................................ 24
4.4.1.
Electricity and Heat........................................................................................................................ 24
4.4.2.
Natural Gas...................................................................................................................................... 24
4.4.3.
Oil ...................................................................................................................................................... 25
4.4.4.
Solid Fuels and Manufactured Gases ......................................................................................... 26
4.4.5.
Renewables and Waste ................................................................................................................ 26
4.4.6.
Conversion Equivalents ................................................................................................................. 27
5.
END USE ......................................................................................................... 29
5.1.
SPACE HEATING ........................................................................................ 29
5.1.1.
Main/Supplementary Space Heating System ........................................................................... 29
5.1.2.
Collective/Individual Space Heating System ............................................................................ 29
5.1.3.
Type of Heating Equipment .......................................................................................................... 30
5.1.4.
Age of Heating Equipment ........................................................................................................... 31
5.1.5.
Availability and type of temperature control instruments (thermostats). ............................ 31
5.2.
WATER HEATING ........................................................................................ 31
5.2.1.
Type of water heating Equipment............................................................................................... 31
5.2.2.
Tank size, age .................................................................................................................................. 32
5.2.3.
Main/Secondary Water Heating equipment ............................................................................ 32
5.3.
COOKING .................................................................................................. 32
5.3.1.
Cooking Equipment ....................................................................................................................... 32
5.3.2.
Main/Secondary Cooking Equipment ........................................................................................ 32
5.3.3.
Age of Primary Cooking Equipment ........................................................................................... 32
5.4.
SPACE COOLING ...................................................................................... 32
5.4.1.
Air conditioning ............................................................................................................................... 33
5.4.2.
Air conditioning equipment type ................................................................................................ 33
5.4.3.
Age ................................................................................................................................................... 33
5.4.4.
Thermostat types ............................................................................................................................ 33
5.5.
LIGHTING AND ELECTRICAL APPLIANCES .............................................. 33
5.5.1.
Refrigeration .................................................................................................................................... 33
5.5.2.
Laundry............................................................................................................................................. 33
5.5.3.
Dishwashing ..................................................................................................................................... 33
5.5.4.
Home Entertainment ...................................................................................................................... 33
5.5.5.
Home Office .................................................................................................................................... 34
5.5.6.
Rechargeable devices.................................................................................................................. 34
5.5.7.
Cleaning and small equipment not included in other main end uses ................................. 34
5.5.8.
Lighting ............................................................................................................................................. 34
5.6.
OTHERS END USES...................................................................................... 34
5.6.1.
Stand-by ........................................................................................................................................... 34
5.6.2.
Lifts or elevators............................................................................................................................... 34
5.6.3.
Garden equipment. ....................................................................................................................... 34
6.
PENETRATION OF ENERGY EFFICIENCY TECHNOLOGIES......................... 35
6.1.
PENETRATION OF LABELLED APPLIANCES / EQUIPMENT ...................... 35
6.2.
IMPROVEMENT WORK (BY TYPE) CARRIED OUT IN THE DWELLING AND
THE HEATING / AIR-CONDITIONING EQUIPMENT WITH A VIEW TO IMPROVED
ENERGY SAVING .................................................................................................. 35
6.3.
PENETRATION OF HIGH-EFFICIENCY CONDENSING BOILERS .............. 35
6.4.
DIFFUSION OF HIGH EFFICIENCY BULBS .................................................. 35
7.
ENERGY SERVICE DEMAND ......................................................................... 36
7.1.
INTENSITY OF USE OF HEATING SYSTEM AND THERMOSTAT SET POINTS
DURING THE HEATING PERIOD ........................................................................... 36
7.2.
INTENSITY OF USE OF AIR-CONDITIONING SYSTEM AND THERMOSTAT
SET POINTS DURING THE COOLING PERIOD ..................................................... 36
8.
PENETRATION OF RENEWABLE ENERGY SOURCES ................................... 37
8.1.
GEOTHERMAL ............................................................................................ 37
8.2.
HYDRO POWER ......................................................................................... 37
8.3.
SOLAR ENERGY ......................................................................................... 37
8.3.1.
Solar photovoltaic. ......................................................................................................................... 37
8.3.2.
Solar thermal. .................................................................................................................................. 37
8.4.
WIND ........................................................................................................... 38
8.5.
SOLID BIOMASS AND BIOGAS. ................................................................ 38
9.
ENERGY POVERTY ......................................................................................... 39
9.1.
ENERGY POVERTY RATIO.......................................................................... 43
9.2.
ENERGY POOR HOUSEHOLD ................................................................... 43
9.3.
ADEQUATE LEVEL OF WARMTH ............................................................... 43
9.4.
PRIMARY HEATED ZONE ........................................................................... 43
9.5.
SECONDARY HEATED ZONE..................................................................... 43
9.6.
UNHEATED ZONE ....................................................................................... 43
9.7.
UNDER-OCCUPATION .............................................................................. 43
9.8.
SURPLUS BEDROOMS ................................................................................ 44
9.9.
NUMBER OF BEDROOMS REQUIRED ....................................................... 44
9.10.
SURPLUS FLOOR AREA ........................................................................... 44
9.11.
STANDARD
LIVING
AREA
REQUIRED
FOR
THE
NUMBER
OF
OCCUPANTS. ....................................................................................................... 44
9.12.
HEATING REGIME ................................................................................... 44
9.12.1.
Heating Pattern .......................................................................................................................... 45
9.12.2.
Heating Extent ............................................................................................................................ 45
9.13.
LENGTH OF THE HEATING SEASON ...................................................... 45
9.14.
GAIN TO LOSS RATIO............................................................................. 45
9.15.
DIMENSIONS OF THE DWELLING AND, IN PARTICULAR, THE HEATED
VOLUME AND HEAT LOSS AREAS....................................................................... 45
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
1. INTRODUCTION
Eurostat, playing its role as coordinator of the Statistical European System, contributes to
the statistical planning and harmonization for all the State Members. The main objective of
Eurostat is the development, improvement and strengthening of the European statistics,
favouring the harmonization of the statistical information for the evaluation of public
policies. With this purpose, Eurostat has developed the MESH Project, in order to deepen
the amount and quality of data on energy consumption in the residential sector, which is
one of the sectors with greater lacks in this field. Within the framework of this project, and
after analyzing the corresponding situation of each country, establishing best practices
both
geographically
and
according
to
statistical
methods,
standardizing
the
methodologies, and making the appropriate recommendations to each EU member
country, it is fundamental to provide a standard of concepts, that is, an operational list of
variables and their definitions which allows the harmonization of the statistical information
on energy consumption in households, which must be based on the principles of
coherence, comparability and capacity of being integrated.
Eurostat defines standardization as the creation and utilization of directives for the uniform
production of interchangeable components, especially those used in mass production. It
also makes reference to the establishment or adoption of guidelines on behaviour or
methods, for the development of a specific process.
Thus, the standardization of concepts is presented as a fundamental tool for the
harmonization of statistical information, because it establishes the necessary norms and
characteristic features to be followed by all the countries that attempt to lay down such
standardization.
Hence, the purpose of this report is the production of a glossary of standardized variables,
concepts and definitions in the field of energy consumption in households, to be
commonly used in the statistical operations related to that subject within the EU, with the
purpose of allowing the comparability of the information produced.
This operational list of variables and definitions will also make possible:

To dispose in an ordered and systematized way the concepts which have been
used for the statistical production.

To compare concepts and definitions with other national and international
standards.

To provide the users with clear, concise and standardized concepts which serve as
a help for the interpretation of statistics
For establishing the operational list of variables and concepts, it is necessary first to delimit
which variables are relevant to the subject to be standardized. The variables and
definitions that pertain to the subject to be standardized are those inherent in the
statistical operation, that is, basic and fundamental concepts for the thematic and
8
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
conceptual design of the statistical operation and for its development, and concepts that
are subject of study in the statistical operation and for that reason are the centre and basis
for its development.
It must be pointed out that the standardization of concepts is a continuous process, which
is neither closed nor limited. The variables and definitions established now can change
over time, but the matter is the establishment of unified definitions by general consent.
For the development of this report and the research on standardization of the utilized
concepts, international references have been taken into account in order to reinforce the
conceptual framework of this piece of work. The consulted references are:

American Council for an Energy-Efficient Economy: www.aceee.org

Department of Energy and Climate Change, U.K.: Fuel Poverty Methodology
Handbook. Available at www.decc.gov.uk

Energy
Efficiency
and
Renewable
Energy,
U.S.
Department
of
Energy:
www.eere.energy.gov

Eurostat: Regulation on Energy Statistics.
Available at www.epp.eurostat.ec.europa.eu

IEA-OECD-Eurostat: Energy Statistics Manual. Available at www.iea.org

NSi consortium within the MESH Project, Eurostat: Manual for Statistics on Energy
Consumption in Households (MESH): Definition of the Household Sector, Draft
version: V 1.0 – 12 h July 2012.

United Nations Statistics Division (2011). International Recommendations for Energy
Statistics (IRES). Draft version. New York.
After this introduction (chapter 1), in the following pages a structure of variables/definitions
has been developed according to the following classification categories:
2. Housing stock characteristics
3. Households characteristics
4. Consumption/Expenditure of energy commodities
5. End-uses
6. Penetration of energy efficiency technologies
7. Energy service demand
8. Penetration of renewable energy sources
9. Energy poverty
9
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
2. HOUSING STOCK CHARACTERISTICS
Information on dwelling characteristics affecting energy consumption.
This section takes as main reference the document Definition of the Household Sector,
Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH Project.
To start with, collective residences and private residences can be differentiated.
Collective residences, which can be permanent (i.e.: prisons, quarters for soldiers, colleges,
etc.) or temporary (i.e.: hotels, hospitals, etc.), are excluded from the sector that is the
subject of study, which is focused in private residences.
DWELLING
2.1.
The physical structure (a house, an apartment, a group of rooms, or a single room)
that is either occupied or intended for occupancy by the members of a
household.
Regarding energy consumption in households, only occupied dwellings are
relevant.
OWNED/RENTED
2.2.
A dwelling is classified as "owned" when the owner or co-owner is a household
member. Dwellings bought on mortgage are included under this heading. The
ownership refers to the structure itself (not to the land). A dwelling is classified as
rented when it is occupied or used in return for regular payments by the tenant or a
third person.
DWELLING TYPE:
2.3.
While an elaborate classification of dwellings
may be used, a simple typology
could be limited to Single Houses and Apartments.
2.3.1.
Single House
A dwelling, detached or attached, that provides living space for one
household.
10
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
2.3.2.
Apartment
A dwelling in a building that contains living quarters for more than one
household and in which households live above, below or beside other
households.
However, it is recommended to break down both these two basic categories,
differentiating detached, semidetached and terraced houses in the category
“Single House”, and low and high rising apartment buildings concerning the
category “Apartment”, because , as IDAE comments, all these factors affect
energy consumption. Regarding the height of an apartment building, it is
necessary to delimit the threshold that differentiates between low and high rising
buildings.
2.4.
URBAN/RURAL
Classification of dwellings as being located in a city / town / suburb/ rural / open
country.
This classification is relevant because in suburb, rural and open country locations
detached houses are relatively much more abundant than in cities or towns.
Additionally, households incomes differ substantially in general terms between rural
and urban areas, which affects the physical characteristics of the dwellings, the
types of technologies and the equipments involved in energy consumption in
households. Moreover, energy facilities tend to be scarcer in rural areas, which
results in differences from the supply side that imply differences in systems and
equipments related to energy consumption in dwellings.
As an operational criterion, rural areas may be delimited according to the number
of inhabitants of the municipality. As within Europe the territorial and population
distributions are quite different, this operational criterion might be established
according to a threshold pertaining to an interval of inhabitants, whose precise
value could be set for each specific European country or region.
2.5.
HEATED FLOOR SPACE
The floor area of a dwelling heated during most of the winter months. Rooms that
are unoccupied during the heating season, unheated garages or other unheated
areas in the basement and / or the attic are not counted.
The expression “floor interior area” is richer, as the relevant purpose of the end use
space heating is related to indoor areas.
11
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
As an operational criterion a correction factor could be applied to the floor area of
the dwellings according to the presence of terraces, garages, basements or attics,
and the households should be required in the corresponding information sources to
report the extent of these areas.
In fact the heated volume is the most appropriate concept regarding space
heating. This should be estimated considering an average ceiling height for each
dwelling, taking into account broad classes of dwellings according to the factors
that influence this average ceiling height, such as period of construction or type of
dwelling.
2.6.
AIR-CONDITIONED FLOOR SPACE
The floor area of the dwelling that is cooled during most of the summer months.
The same comments made in the previous point “Heated Floor Space” are
relevant to the “Air-conditioned Floor Space”.
2.7.
BUILDING ENVELOPE
The “building envelope” refers to the external walls, windows, roof, and floor of the
building where the dwelling is placed. This barrier between indoors and outdoors is
important with regards to ventilation and insulation of a conditioned space.
2.8.
COMMUNAL AREAS OF THE BUILDING
This concept may be relevant to all type of dwellings. The communal areas of a
building are those areas of the building, or of its associated land, for the use of all
the occupants of the dwellings. The amount of usage of the communal areas of
the building for each occupant or each dwelling cannot be determined.
2.9.
DWELLINGS BY PERIOD OF CONSTRUCTION
The period (e.g. 1950-1973) when the building in which the dwelling is placed was
completed.
This variable affects energy efficiency related to the end uses space heating and
space cooling, and dwelling characteristics. An international comparison among
dwellings by period of construction is very difficult. In any case, this variable should
be taken into account, and in a way that allows comparability. For that reason, an
operational criterion could consist in considering decades. Other operational
criterion, focused on energy efficiency, could consist in fixing a specific year for all
the European countries, considered as the date from which relevant energy
efficiency technologies start to be applied to buildings, with European territorial
12
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
signification, and then differentiating between dwellings built after and before that
year.
2.10.
AVAILABILITY OF INSULATION
Presence of thermal insulation of external walls, floor, loft/roof or windows.
As regards availability of construction, the period of construction of the dwelling,
and renovations, are two key variables. So, surveys should include questions to
determine the contents of the performed renovations (façade, roofs, windows,…)
and when they were made.
13
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
3. HOUSEHOLD CHARACTERISTICS
Household characteristics affecting energy consumption.
This section takes as main reference the document Definition of the Household Sector,
Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH Project.
According to the NSi consortium involved in the MESH Project, secondary residences are
excluded from the research in order to establish a homogeneous system of statistics for
measuring energy consumption in households. Nevertheless, the case of the secondary
residences is analogous to that of the primary residences; as in the field of energy
consumption the latter is more extensive, the intended methodology focuses on it.
HOUSEHOLD
3.1.
A family, an individual, or a group of unrelated persons occupying the same
dwelling. Household members include all persons who usually live in the dwelling
(even if they are temporarily absent at the time of the interview, as persons
travelling, in hospital etc). Household members who are away from home on
extended periods (as college students, members of the armed forces etc) do not
count.
3.2.
NUMBER OF OCCUPANTS OF A DWELLING
The number of occupants of a dwelling is the number of people for whom the
dwelling is the usual residence.
This variable has a key impact in energy consumption in households, though in
some energy end uses its effects are far distant from being linear.
3.3.
HOUSEHOLD INCOME
The income combines the total income from all sources (before taxes and
deductions) of all household members, during a twelve month period. Income
comprises: wages, salaries, pensions, commissions, interest, dividends, rental
income, social security, unemployment compensation or any other public
assistance.
14
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
ECONOMIC ACTIVITY
3.4.
The subject to be covered by the research in order to establish a
homogeneous system of statistics for measuring energy consumption in
households consists in private consumption of energy by households in their
main residence. As a result of this definition, transport energy consumption in
households and consumption of energy for performing economic activities in
dwellings in order to raise income.
The variable “Economic Activity” must measure home-based economic
activity – practised by the household - that uses important amounts of energy.
A broad classification (farming, other economic activity, both) might be
adequate; further refinement of economic activities (according to NACE) may
be
pursued.
While
introducing
uncertainties,
energy
consumption
in
households will be reported net of energy use in home-related economic
activities.
3.5.
PRIMARY RESIDENCE
A dwelling which is the usual place of residence of the householder; it is
occupied for at least half of the year by the householder.
3.6.
SECONDARY HOMES
A dwelling which is occupied for less than six months of the year by the
householder. It will not be counted in the surveys.
15
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
4. CONSUMPTION/EXPENDITURE OF ENERGY COMMODITIES
The points 4.1 and 4.2 in this section takes as main reference the document Definition of
the Household Sector, Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in
the MESH Project.
The point 4.3 in this section takes as main references the Regulation on Energy Statistics by
Eurostat, and the International Recommendations for Energy Statistics (IRES) by the United
Nations Statistics Division (2011). The point 4.4 takes as main reference the IEA-OECDEurostat Energy Statistics Manual.
4.1.
CONSUMPTION
The amount of energy commodities consumed by a household during a twelvemonth period.
For fuels that may be stocked and are purchased in the market, consumption, as a
first approximation, represents fuel purchased, not fuel consumed, over this twelvemonth period. However it would be desirable to estimate in these cases the actual
consumption attributable to the year, as it is made in the energy balances at a
macro level. For this purpose specific questions may be asked in the surveys.
Renewable energies consumption in households must be estimated by means of
the
information
sources
available
or
by
means
of
modelling
or
other
methodologies. For this purpose information about the equipments that produce
them is needed.
Correction for climate is relevant to methods like modelling and to purposes like
fuel poverty or energy planning, but is not relevant to measure actual
consumption.
4.2.
EXPENDITURE
Money spent for the energy used in, or delivered to, a dwelling on an annual basis.
The amount comprises VAT and other taxes. Electricity and natural gas
expenditures cover the amount of these energy commodities that are consumed.
For fuels that may be stocked, expenditure covers the amount of fuel purchased,
which may differ from the amount of fuel consumed; however in this case it would
be useful to impute the costs attributable to the year, in line with the comment
made in the previous point “Consumption”.
16
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
ENERGY COMMODITIES
4.3.
Definitions are reported according to the Energy Statistics Regulation of the EU
(2010),
and
complemented
when
it
is
necessary
with
the
International
Recommendations for Energy Statistics (IRES) by the United Nations Statistics Division
(2011). The focus is on commodities related to energy consumption in the
residential sector; these appear in bold, and the complete classification which
includes them, till they are reached, is reported for illustrative reasons.
Fuel is any substance burned as a source of heat or power. The provision of energy
as heat or power in either mechanical or electrical form is the major reason for
burning fuels. The term energy, when used accurately in energy statistics, refers only
to heat and power but it is loosely used by many persons to include the fuels. The
term energy commodity will be used in this report when a statement covers both
fuels and heat and power. However, other energy statisticians may use synonyms
like energy carrier, energy vector or energyware.
4.3.1.
Electricity and Heat
4.3.1.1.
Electricity supplied from the mains.
4.3.1.2.
District heating
Heating plant or boiler rooms for several buildings. If the source of this
commodity is the geothermal energy, then this energy commodity is
reported in the category of Renewables and Waste.
4.3.2.
Natural Gas
Natural gas comprises several gases, but consists mainly of methane (CH4).
When extracted from a gas field or in association with crude oil, it comprises a
mixture of gases and liquids (some of them will not be energy commodities).
Only after processing does it become one of the marketable gases among the
original mixture.
Natural gas also includes methane recovered from coal mines (colliery gas) or
from coal seams (coal seam gas) and shale gas. When distributed it may also
contain methane from anaerobic fermentation or the methanation of
biomass.
To facilitate transportation over long distances, natural gas may be converted
to liquid form by reducing its temperature to –160 degrees Celsius under
atmospheric pressure. When gas is liquefied, it is called liquefied natural gas
(LNG).
17
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
4.3.3.
Oil
Petroleum is a complex mixture of liquid hydrocarbons, chemical compounds
containing hydrogen and carbon, occurring naturally in underground
reservoirs in sedimentary rock. Coming from the Latin petra, meaning rock, and
oleum, meaning oil, the word “petroleum” is often interchanged with the word
“oil”.
Following the International Recommendations for Energy Statistics (IRES) by the
United Nations Statistics Division (2011), the term oil means liquid hydrocarbons
of fossil origins comprising (i) crude oil;(ii) liquids extracted from natural gas
(NGL); (iii) fully or partly processed products from the refining of crude oil, and
(iv) functionally similar liquid hydrocarbons and organic chemicals from
vegetal or animal origins. This classification is detailed below, and the energy
commodities relevant to the residential sector are in bold.
4.3.3.1.
Conventional crude oil
A mineral oil of fossil origin extracted by conventional means from
underground
reservoirs,
and
comprises
liquid
or
near-
liquid
hydrocarbons and associated impurities such as sulphur and metals.
Remark: Conventional crude oil exists in the liquid phase under normal
surface temperature and pressure, and usually flows to the surface under
the pressure of the reservoir. Crude oil includes condensate from
condensate fields, and “field” or “lease” condensate extracted with the
crude oil. The various crude oils may be classified according to their
sulphur content (“sweet” or “sour”) and API gravity (“heavy” or “light”).
Crude oil is the most important oil from which petroleum products are
manufactured.
There
is
a
wide
range
of
petroleum
products
manufactured from crude oil. In the residential sector liquefied
petroleum gases (LPG), kerosene, heating gas oil and heavy oil are the
most relevant.
i. Liquefied petroleum gases (LPG)
LPG refers to liquefied propane (C3H8) and butane (C4H10) or
mixtures of both. Commercial grades are usually mixtures of the gases
with small amounts of propylene, butylene, isopropylene and
isobutylene stored under pressure in containers.
Remark: The mixture of propane and butane used varies according to
purpose and season of the year. The gases may be extracted from
natural gas at gas separation plants or at plants re-gasifying imported
liquefied natural gas. They are also obtained during the refining of
crude oil. LPG may be used for heating and as a vehicle fuel.
Certain oil field practices also use the term LPG to describe the high
vapour pressure components of natural gas liquids.
They are often used in domestic or residential heating and cooking.
18
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
ii. Kerosenes
Mixtures of hydrocarbons in the range C9 to C16 and distilling over the
temperature interval 145ºC to 300°C, but not usually above 250ºC and
with a flash point above 38ºC.
Remark: The chemical compositions of kerosenes depend on the
nature of the crude oils from which they are derived and the refinery
processes that they have undergone.
Kerosenes obtained from crude oil by atmospheric distillation are
known as straight-run kerosenes. Such streams may be treated by a
variety of processes to produce kerosenes that are acceptable for
blending as jet fuels. Kerosenes are primarily used as jet fuels. They are
also used as domestic heating and cooking fuels, for lighting and as
solvents. Kerosenes may include components or additives derived
from biomass.
iii. Gas oil / Diesel oil
•According to UN (2011(, gas oils are middle distillates, predominantly
of carbon number range C11 to C25 and with a distillation range of
160ºC to 420°C.
Remark: The principal marketed products are fuels for diesel engines
(diesel oil), heating oils and marine fuel.
Gas oils are also used as middle distillate feedstock for the
petrochemical industry and as solvents.
The main difference between diesel and heating oil is the sulphur
content of the fuel – for environmental purposes, the specification of
the sulphur content for transport diesel is much lower than that of
heating oil.
•According to EU (2010), Gas/Diesel Oil, also named Distillate Fuel Oil,
is primarily a medium distillate distilling between 180 °C and 380 °C. It
includes
blending
components.
Several
grades
are
available
depending on uses. Heating and Other Gas oil pertains to this
category and is light heating oil for industrial and commercial uses,
marine diesel and diesel used in rail traffic, other gas oil including
heavy gas oils which distil between 380 °C and 540 °C and which are
used as petrochemical feedstocks.
iv. Heavy gas oil
A mixture of predominantly gas oil and fuel oil which distills in the
range of approximately 380ºC to 540ºC.
4.3.3.2.
Natural gas liquids (NGL)
Natural gas liquids are a mixture of ethane, propane, butane (normal
and iso), (iso) pentane and a few higher alkanes collectively referred to
as pentanes plus.
Remark: NGL are produced in association with oil or natural gas. They
are removed in field facilities or gas separation plants before sale of the
19
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
gas. All of the components of NGL except ethane are either liquid at the
surface or are liquefied for disposal.
The definition given above is the most commonly used. However, there is
some use of terms based on the vapour pressure of the components
which are liquid at the surface or can be easily liquefied. The three
resulting groups are in order of increasing vapour pressure: condensates,
natural gasoline and liquefied petroleum gas.
NGL may be distilled with crude oil in refineries, blended with refined oil
products or used directly. NGL differs from LNG (liquefied natural gas)
which is obtained by liquefying natural gas from which the NGL has been
removed.
4.3.3.3.
Refinery feedstocks and additives and oxygenates
4.3.3.4.
Other hydrocarbons
This division
includes
non-conventional
oils and
hydrogen. Non-
conventional oils refer to oils obtained by non-conventional production
techniques. They also include the oils extracted from oil sands, extra
heavy oils, coal and oil shale which are at, or can be brought to, the
surface without treatment and require processing after mining (ex situ
processing). Non-conventional oils may also be produced from natural
gas.
Remark: The oils may be divided into two groups: (i) oils for transformation
(e.g., synthetic crudes extracted from extra heavy oils, oil sands, coal
and oil shale); and (ii) oils for direct use (e.g., emulsified oils such as
orimulsion and GTL liquids).
4.3.4.
Solid Fuels and Manufactured Gases
Solid fuels and manufactured gases cover various types of coals and products
derived from coals by carbonization or pyrolysis processes, by the aggregation
of finely divided coal or by chemical reactions with oxidizing agents, including
water.
Remark: There are two main categories of primary coal, hard coal (comprising
medium and high-rank coals) and brown coal (low-rank coals) which can be
identified by their Gross Calorific Value - GCV and the Vitrinite mean Random
Reflectance per cent. The IEA-OECD-Eurostat Manual (2005) distinguishes
another category, sub-bituminous coal, which includes non-agglomerating
coal with a GCV comprised between those of the other two categories.
Peat is included in this category of Solid Fuels and Manufactured Gases.
4.3.4.1.
Hard coal
Coals with a gross calorific value (moist, ash-free basis) which is not less
than 24 MJ/kg or which is less than 24 MJ/kg provided that the coal has
20
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
a vitrinite mean random reflectance greater than or equal to 0.6 per
cent. Hard coal comprises anthracite and bituminous coals.
Anthracite is a high-rank, hard coal with a gross calorific value (moist,
ash- free basis) greater than or equal to 24 MJ/kg and a Vitrinite mean
Random Reflectance greater than or equal to 2.0 per cent.
Remark: It usually has less than 10% volatile matter, high carbon content
(about 86-98% carbon) and is non-agglomerating. Anthracite is mainly
used for industrial and household heat raising.
Bituminous coal is a medium-rank hard coal with either a gross calorific
value (moist, ash-free basis) not less than 24 MJ/kg and with a Vitrinite
mean Random Reflectance less than 2.0 per cent, or a gross calorific
value (moist, ash- free basis) less than 24 MJ/kg provided that the Vitrinite
mean random reflectance is equal to or greater than 0.6 per cent.
Remark: Bituminous coals are agglomerating and have a higher volatile
matter and lower carbon content than anthracite. They are used for
industrial coking and heat raising and household heat raising.
4.3.4.2.
Sub-Bituminous Coal
•According to EU (2010) it refers to non-agglomerating coal with a gross
calorific value between 17 435 kJ/kg (4 165 kcal/kg) and 23 865 kJ/kg (5
700 kcal/kg) containing more than 31 % volatile matter on a dry mineral
matter free basis.
4.3.4.3.
Brown coal
•According to UN (2011) it makes reference to coals with a gross calorific
value (moist, ash- free basis) less than 24 MJ/ kg and a Vitrinite mean
Random Reflectance less than 0.6 per cent.
Remark: Brown coal comprises sub-bituminous coal and lignite.
•According to EU (2010), Lignite/Brown Coal is a non-agglomerating
coal with a gross calorific value less than 17 435 kJ/kg (4 165 kcal/kg)
and greater than 31 % volatile matter on a dry mineral matter free basis.
4.3.4.4.
Peat
It is a solid formed from the partial decomposition of dead vegetation
under conditions of high humidity and limited air access (initial stage of
coalification). It is available in two forms for use as a fuel, sod peat and
milled peat.
Remark: Peat is not considered a renewable resource as its regeneration
period is long.
They can be distinguished Sod peat (Slabs of peat, cut by hand or
machine, and dried in the air), Milled peat (Granulated peat produced
by special machines, and is used in power stations or for briquette
manufacture), Peat products (which includes products such as peat
21
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
briquettes derived directly or indirectly from sod peat and milled peat),
Peat briquettes, which is a fuel comprising of small blocks of dried, highly
compressed peat made without a binding agent and is used mainly as a
household fuel, and Other peat products (peat products not elsewhere
specified such as peat pellets).
4.3.4.5.
Coal products
This division includes products derived directly or indirectly from the
various classes of coal by carbonization or pyrolysis processes, or by the
aggregation of finely divided coal or by chemical reactions with
oxidizing agents, including water. The main commodities regarding
consumption in households are the following:
i. Semi-coke
It is a solid product obtained from carbonization of coal at low
temperature. Semi-coke is used as a domestic fuel or by the
transformation plant itself. This heading also includes coke, coke
breeze and semi-coke made from lignite/brown coal.
ii. BKB (Brown Coal Briquettes)
•According to EU (2010), BKB is a composition fuel manufactured from
lignite/brown coal, produced by briquetting under high pressure
without the addition of a binding agent. It includes peat briquettes,
dried lignite fines and dust.
•According to UN (2011), it is a composition fuel made of brown coal
produced by briquetting under high pressure with or without the
addition of a binding agent.
Remark: Either sub-bituminous coal or lignite may be used, including
dried lignite fines and dust.
iii. Gas Works Gas
Covers all types of gases produced in public utility or private plants,
whose main purpose is manufacture, transport and distribution of gas.
It includes gas produced by carbonization (including gas produced
by coke ovens and transferred to gas works gas), by total gasification
with or without enrichment with oil products (LPG, residual fuel oil,
etc.), and by reforming and simple mixing of gases and/or air,
reported under the rows “From Other Sources”.
4.3.5.
Renewable Energy and Energy from Waste
Renewable energy is energy that is derived from natural processes that are
replenished constantly (this definition leads to some issues, dealing for instance
with the time horizon for the replenishment).
Waste is a fuel consisting of many materials coming from combustible
industrial, institutional, hospital and household wastes such as rubber, plastics,
22
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
waste fossil oils and other similar commodities. It is either solid or liquid in form,
renewable or nonrenewable, biodegradable or non-biodegradable.
The relevant commodities in this category for energy consumption in
households are listed below.
4.3.5.1.
Geothermal
Energy available as heat emitted from within the earth’s crust, usually in
the form of hot water or steam. It is exploited at suitable sites, in the case
of households, directly as heat for district heating.
4.3.5.2.
Hydro power
Potential and kinetic energy of water. It can be converted into electricity.
4.3.5.3.
Solar energy
Solar radiation exploited for hot water production and electricity
generation. This energy production is the heat available to the heat
transfer medium, i.e. the incident solar energy less the optical and
collectors losses. Passive solar energy for the direct heating, cooling and
lighting of dwellings or other buildings is not included. Solar energy can
mainly be of two types, Solar Photovoltaic and Solar Thermal.
i. Solar Photovoltaic
Sunlight converted into electricity by the use of solar cells usually
made of semi- conducting material which exposed to light will
generate electricity.
ii. Solar Thermal
Heat from solar radiation. It is captured in households by equipment
for the production of domestic hot water or for the seasonal heating
of swimming pools (e.g. flat plate collectors, mainly of the
thermosyphon type).
4.3.5.4.
Wind
Kinetic energy of wind. It can be exploited for electricity generation in
wind turbines.
4.3.5.5.
Solid Biomass
It covers organic, non-fossil material of biological origin which may be
used as fuel for heat production or electricity generation. It comprises
Charcoal, and Wood, Wood Wastes and Other Solid Wastes.
i. Charcoal
The solid residue of the destructive distillation and pyrolysis of wood
and other vegetal material.
23
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
ii. Wood, Wood Wastes and Other Solid Wastes
Purpose-grown energy crops (poplar, willow etc.), a multitude of
woody materials generated by an industrial process (wood/paper
industry in particular) or provided directly by forestry and agriculture
(firewood, wood chips, wood pellets, bark, sawdust, shavings, chips,
black liquor etc.) as well as wastes such as straw, rice husks, nut shells,
poultry litter, crushed grape dregs etc. Combustion is the preferred
technology for these solid wastes.
Biogas
4.3.5.6.
A gas composed principally of methane and carbon dioxide produced
by anaerobic digestion of biomass. There are many kinds of biogas. In
energy consumption in households, the most relevant is the Sewage
Sludge Gas, which is a biogas produced from the anaerobic
fermentation of sewage sludge.
UNITS OF MEASUREMENT OF ENERGY COMMODITIES IN THE
4.4.
RESIDENTIAL SECTOR AND CONVERSION EQUIVALENTS
The units of measurement of energy, mass, and volume, most widely accepted
across the world are those of the Système International d'Unités (SI). This system is
and international standardization of the units of measurement of all physical
concepts.
4.4.1.
Electricity and Heat
Units of energy: The SI unit of energy is the joule (J). Within the SI, energy can
be expressed in a multiple of watt-hours.
For households, electricity consumption is reported in kilowatt-hours. One joule
is equal to one watt-second. So a kilowatt-hour is equal to 3,600,000 joules, that
is, 3.6 megajoules.
Yearly heat consumption of a dwelling is expressed in gigajoules, according to
the SI.
Alternatively, the whole energy consumption of a dwelling may be reported in
gigajoules.
4.4.2.
Natural Gas
Fuels are naturally expressed in units of mass or volume. It order to obtain the
energy value of an energy commodity expressed in mass or volume, the so
called calorific value, or heating value, per unit of mass or volume is needed.
The calorific value makes reference to the energy, in the form of heat, which is
produced by means of the combustion of the fuel. The gross value includes all
24
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
of the heat released from the fuel, including any carried away in the water
formed during combustion. The net value excludes the latent heat of the
water formed during combustion and the heat dismissed during combustion
owed to the presence of impurities.
The difference between net and gross is typically about 10% for natural gas.
Energy content of natural gas and manufactured gases is expressed in gross
calorific value (GCV).
Natural gas consumption of a household is reported in cubic metres,
according to the SI. When using volume measurements for natural gas, it is
important to know at which temperature and under which pressure the gas
has been measured. Indeed, as gas is very compressible, volumes of gas have
meaning only at an agreed specific temperature and pressure. There are two
sets of conditions under which gas can be measured:
- Normal conditions: measured at a temperature of 0 degrees Celsius and a
pressure of 760 mm Hg.
- Standard conditions: measured at a temperature of 15 degrees Celsius and a
pressure of 760 mm Hg.
The conversion to energy units (joules) must be done using the gross calorific
value of the flow concerned. Each of the gas flows may have a different
calorific value, and within each flow, the components might have different
values (e.g. production from various fields of differing gas qualities, or imports
from different sources). Calorific values also change over time. The relevant
gross calorific values may be obtained from the gas supply industry.
4.4.3.
Oil
Liquid fuels can be measured by their mass or volume, and then, concerning
the yearly consumption of a household, they are expressed in litres (volume) or
in kilograms (mass), within the SI. One litre is equal to 0.001 cubic metres, and
the cubic metre and the kilogram are respectively the units of measurement of
volume and mass within the SI.
As liquid fuels can be measured by their mass or their volume, it is essential to
be able to convert one into the other. In order to make this conversion, the
specific gravity or density of the liquid is needed. Density is defined as mass per
unit volume. The specific gravity is the relative weight per unit volume (or
density) of a given substance compared to that of water. Since volume
changes with changes in temperature, data on specific gravity are reported
with a reference to a specific temperature. Moreover, specific gravity is often
quoted as a percentage, e.g. a specific gravity of 0.89 is shown as 89.
The term API gravity (a standard adopted by the American Petroleum Institute)
is commonly used to express the specific gravity of petroleum.
Nota bene: API gravity is defined as: (141.5 / 60o specific gravity at 60o F ) –
131.5.
25
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
Specific gravity and API gravity move in opposite directions. API gravity moves
in the same direction as energy content per tonne, i.e. the higher the API
gravity, the higher the energy content per tonne, whereas specific gravity
moves in the same direction as energy content per unit volume.
The difference between net and gross calorific value is typically about 5% to
6% of the gross value for liquid fuels. Energy content of liquid fossil fuels is
expressed in net calorific value (NCV).
4.4.4.
Solid Fuels and Manufactured Gases
Solid fuels are usually measured by mass. In some technical reports, coal data
can also be found in terms of tonnes of coal equivalent (tce). The tonne of
coal equivalent is not a unit of mass but a unit of energy that is more widely
used in the international coal industry to make comparisons between various
fuels. A tonne of coal equivalent is defined as 7 million kilocalories. The relation
between tonne of oil equivalent (toe) and tonne of coal equivalent is: 1 tce =
0.7 toe.
The calorific values for the respective solid fossil fuels can dramatically vary
from product to product, and for each product, the different flows may have
different values. Moreover, calorific values can change over time owing to
changes of processes and/or technology. They are expressed as net calorific
values.
Manufactured gases can be measured in several units: either according to
energy content (also referred to as heat) or volume. Within each of these
measurements, several units are used in the natural gas industry:
- In order to measure energy, it is possible to use joules, calories, kWh, British
Thermal Units (Btu), or therms; always expressing gross calorific value.
- In order to measure volume, the most frequently used unit is the cubic metre
or cubic foot.
The differences between net and gross are typically about 5% to 6% of the
gross value for solid and liquid fuels.
4.4.5.
Renewables and Waste
Because of their diverse forms, renewables and waste products have
traditionally been measured in a variety of units. Solid products like wood and
wood waste are often measured in volume (cubic metres or cords) and mass
(tonnes) units. Biogases can be measured on a volume basis (cubic metres)
and on an energy content basis (therms or kilowatt-hours), and bioliquids in
terms of volume (litres), mass (tonnes) and/or energy content (joules or
megajoules). Further, electricity-only renewable sources and technologies like
hydro, solar photovoltaic, and wind can be measured only in terms of
electricity output (usually kilowatt-hours). However, in the case of solar panels,
the solar collectors surface is also reported (in m2).
26
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
Total energy content of the fuels should be calculated using the net calorific
value of the respective fuels. The calorific values dramatically vary from biofuel
to biofuel, as well as in function of the specific type, its density and humidity.
Heating values or calorific values of wood are expressed in three common
ways:
a) Per kilogramme of wood.
b) Per solid cubic metre.
c) Per stacked cubic metre (stere).
a) is the more fundamental measure as b) and c) are related to a) through the
density of the wood and the density of packing.
4.4.6.
Conversion Equivalents
4.4.6.1.
Decimal System Prefixes
Multiple
101 deca (da)
102 hecto (h)
103 kilo (k)
106 mega (M)
109 giga (G)
1012 tera (T)
1015 peta (P)
1018 exa (E)
4.4.6.2.
From:
U.S. gallon (gal)
U.K. gallon (gal)
Barrel (bbl)
Cubic foot (ft3)
Litre (l)
Cubic metre (m3)
Sub-multiple
10-1 deci (d)
10-2 centi (c)
10-3 milli (m)
10-6 micro (μ)
10-9 nano (n)
10-12 pico (p)
10-15 femto (f)
10-18 atto (a)
Units of Volume
To: gal U.S.
multiply by:
1
1.201
42.0
7.48
0.2642
264.2
gal U.K.
bbl
ft3
l
m3
0.8327
1
34.97
6.229
0.220
220.0
0.02381
0.02859
1
0.1781
0.0063
6.289
0.1337
0.1605
5.615
1
0.0353
35.3147
3.785
4.546
159.0
28.3
1
1 000.0
0.0038
0.0045
0.159
0.0283
0.001
1
The stere and cord are used exclusively for fuelwood measurement and represent 1 cubic
metre and 128 cubic feet of stacked fuelwood, respectively.
27
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
4.4.6.3.
From:
Kilogramme (kg)
Tonne (t)
Long ton (lt)
Short ton (st)
Pound (lb)
4.4.6.4.
From:
Megajoule (MJ)
kilocalorie
toe
Btu
kilowatt-hour
Units of Mass
To:
kg
multiply by:
1
1000
1016
907.2
0.454
t
lt
st
lb
0.001
1
1.016
0.9072
4.54 x 10-4
9.84 x 10-4
0.984
1
0.893
4.46 x 10-4
1.102 x 10-3
1.1023
1.120
1
5.0 x 10-4
2.2046
2204.6
2240.0
2000.0
1
Units of Energy
To: MJ
multiply by:
1
4.1868 x 10-3
4.1868 x 104
1.0551 x 10-3
3.6
kcal
toe
Btu
kWh
238.8
1
107
0.252
860
2.388 x 10-5
10-7
1
2.52 x 10-8
8.6 x 10-5
947.8
3.968
3.968 x 107
1
3412
0.2778
1.163 x 10-3
11630
2.931 x 10-4
1
There are several definitions of the calorie in use. The conversion equivalent between the
calorie and the joule given here is the International Steam Table (IT) value which is defined
to be 4.1868 joules. Similarly, the internationally agreed value for the British thermal unit
(Btu) is now 1 055.06 joules. The Btu is the basis for the quad (1015 Btu) and the therm (105
Btu).
28
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
5. END USE
The use of energy commodities by a household, in order to obtain a certain service
(heating, cooling, hot water etc.). Six major energy end-uses are distinguished for the
energy consumption in households; space heating, water heating, cooking, space
cooling, lighting and electrical appliances, and other end-uses.
This section takes as main references the document Definition of the Household
Sector, Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH
Project, the American Council for an Energy-Efficient Economy, and the Energy
Efficiency and Renewable Energy web site of the U.S. Department of Energy.
SPACE HEATING
5.1.
The use of energy to provide heat in a dwelling.
A more restrictive but more appropriate definition, according to the nature of
energy end uses in households, is the use of energy to provide heat in an interior
area of a dwelling.
Information on fuel type used must be included.
5.1.1.
Main/Supplementary Space Heating System
The main space-heating system provides most of the heat to the dwelling. The
supplementary space-heating equipment is used less often than the main
space-heating system.
It would be desirable to define a number of indicators that help to differentiate
between main and supplementary space heating system in those cases where
is not clear which system provides most of the heat to the dwelling (i.e.: energy
consumption of the system).
5.1.2.
Collective/Individual Space Heating System
Collective / Individual: The main space-heating system may be a collective
system, serving more than one households. An individual system provides heat
to a single household. District heating forms a separate type of main spaceheating systems.
This is a basic classification, and a more complete one is desirable. On one
hand the individual space heating systems can be further differentiated
between local (stoves, fireplaces, electric radiators, etc.) space heating
systems, and floor central heating for one dwelling. On the other hand the
collective space heating systems can be split into central heating for multiple
dwellings in one building, and district heating (heating plant or boiler rooms for
several buildings).
29
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
5.1.3.
Type of Heating Equipment
5.1.3.1.
Central Steam/Hot Water Space Heating System
It provides steam or hot water to radiators / convectors or pipes (underfloor heating) in a dwelling.
5.1.3.2.
Built-in Electric System
A system of electrical resistances (usually as under-floor heating)
providing heat to individual rooms; the system is part of the building
electrical installation.
5.1.3.3.
Central Warm-Air Space Heating System
It provides warm air through ducts to the dwelling.
5.1.3.4.
Heat Pumps
Devices that bring heat into the dwelling from the environment using a
compressor (mechanical work).
Two main types of heat pumps are used in residential and commercial
applications: air-source heat pumps (by far the most common) and
ground-source (or geothermal) heat pumps. A heat pump works like an
air conditioner in the cooling cycle; in the heating cycle, it simply works in
reverse (i.e. cooling the outside, and venting heat to the inside). Groundsource heat pumps transfer heat through earth or water, whereas airsource heat pumps do so via air. Because heat pumps simply move heat
around rather than creating heat, they can be a very efficient method of
space conditioning, especially in moderate climates.
5.1.3.5.
Stove
A non-portable apparatus that furnishes heat using solid or liquid fuels.
5.1.3.6.
Fireplace
5.1.3.7.
Electric storage heaters, portable electric heaters
5.1.3.8.
Portable kerosene/LPG heaters
5.1.3.9.
Other
Cooking
equipment:
regarding
space
heating
only
the
energy
consumption of this type of equipment directed to this end use is
relevant. So, the consideration of this type of heating system is
appropriate only if the distribution of consumption by uses of these
devices can be estimated.
30
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
5.1.4.
Age of Heating Equipment
Age of the main heating system of the household
Availability and type of temperature control instruments
(thermostats).
5.1.5.
As regards thermostats, it has proven very difficult to achieve realistic
information about their precise management in households (i.e.: the set point
fixed during the heating season). In any case, collecting information about its
availability, type, and frequency of use may be enough, providing that the
average room temperature in dwelling during the heating season can be
estimated by means of any of the statistical sources available (for instance,
simply asking about it to the household).,
5.1.5.1.
Thermostat
A device that turns on or off the heating system so that a desired
temperature is reached in a heated space.
5.1.5.2.
Availability
Number of thermostats controlling the main heating system.
5.1.5.3.
Thermostat types
Manual on-off thermostat, allowing the manual control of the heating
period during the day. Programmable thermostat, designed to adjust
automatically the temperature at different times of the day or night and
days of the week.
WATER HEATING
5.2.
The use of energy to heat water for hot running water, bathing, cleaning and other
non-cooking applications.
Information on fuel type used must be provided.
5.2.1.
Type of water heating Equipment
5.2.1.1.
Combi boiler
A combi boiler is a high-efficiency water heater and a central heating
boiler, combined within one compact unit. No separate hot water vessel
is required, heating water on demand. Type of fuel (according to the
ESR) and age (in broad classes) are relevant.
31
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
5.2.1.2.
Water Heater
A thermally insulated vessel designed for heating and storing hot water.
5.2.1.3.
5.2.2.
Heater instant Domestic Heat Water (DHW)
Tank size, age
The volume (litres) and age of the water heater (volume is not relevant in
heater instant DHW). Broad classes may be used for reporting tank size and
age.
5.2.3.
Main/Secondary Water Heating equipment
COOKING
5.3.
The use of energy to prepare meals and hot drinks.
Information on the type of fuel used must be included.
5.3.1.
Cooking Equipment
The following equipment types may be considered: Cooker, oven, hob,
cooking stove, microwave oven, extractor hood, and minor equipment (i.e.:
hot-water boiler, electric toaster, coffee machine, blender, grill, etc).
5.3.2.
Main/Secondary Cooking Equipment
The main cooking equipment provides most of the services related to this enduse to the dwelling. The supplementary cooking equipment is used less often
than the main cooking equipment.
It would be desirable to define a number of indicators that help to differentiate
between main and supplementary cooking equipment in those cases where is
not clear which system provides most of the services to the dwelling (i.e.:
energy consumption of the system).
5.3.3.
Age of Primary Cooking Equipment
Age of the main cooking equipment of the household
5.4.
SPACE COOLING
The use of energy for cooling and dehumidifying the air in a dwelling by a
refrigeration unit (fans, blowers and other appliances not connected to a
refrigeration unit are not included).
32
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
5.4.1.
Air conditioning
The cooling and dehumidification of a dwelling by refrigeration equipment
(compressor unit).
Residential air conditioning technologies include window air conditioners,
central air conditioners, heat pumps, and passive cooling.
5.4.2.
Air conditioning equipment type
A central system that has ducts to bring cooled air in the individual rooms of
the dwelling or electrically driven individual units providing cooled only to
single rooms.
5.4.3.
Age
The age of the central air-conditioning system or the oldest individual unit.
5.4.4.
Thermostat types
Manual on-off thermostat, allowing the manual control of the cooling period
during the day. Programmable thermostat, designed to adjust automatically
the temperature at different times of the day or night and days of the week.
LIGHTING AND ELECTRICAL APPLIANCES
5.5.
The use of energy by the lights and electrical appliances in a dwelling not included
in other end uses.
The age (in broad classes) examination may be limited to the main ones.
From an operational point of view, only reporting the main types listed below may
be sufficient.
5.5.1.
Refrigeration
Refrigerator, separate freezer, fridge-freezer,
5.5.2.
Laundry
Clothes washer, clothes dryer, clothes washer-dryer, iron.
5.5.3.
Dishwashing
Dishwasher.
5.5.4.
Home Entertainment
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
Colour televisions, cable networks, satellite antennas, VCR / DVD and music
equipment, video game console.
5.5.5.
Home Office
Personal computer, printer, internet/modem, fax, photocopier, multi-function
printer/scanner/copier, computer speakers, monitor, USB hub.
5.5.6.
Rechargeable devices
Power Tool, Hand-Held Vacuum, Cordless Phone, Electric Toothbrush, Shaver,
MP3 Player, Cell Phone, Digital Camera.
Cleaning and small equipment not included in other main end
uses
5.5.7.
Vacuum-cleaner, ceiling fans, blowers, humidifier.
5.5.8.
Lighting
Incandescent lamps (or "bulbs"), fluorescent tube lamps, compact fluorescent
lamps (CFLs), halogen lighting, LED lamps.
OTHERS END USES
5.6.
5.6.1.
Stand-by
Standby, or “phantom” power is the power used by electronics and
appliances when they are not performing their main function. In some
products, standby power represents the majority of their annual energy use. In
other cases, the standby power of a device may be relatively low, but
because of the ubiquity of the product the aggregate standby power
consumption may represent a significant amount of energy at a national level.
5.6.2.
Lifts or elevators
They are relevant mainly in high rising apartment buildings. In the latter, this
end use is consumed communally.
5.6.3.
Garden equipment.
All those devices used for gardening that consume energy.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
6. PENETRATION OF ENERGY EFFICIENCY TECHNOLOGIES
This section takes as main reference the document Definition of the Household Sector,
Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH Project.
6.1.
PENETRATION OF LABELLED APPLIANCES / EQUIPMENT
Energy efficiency (classes A+++, A++, A+ and A to G, according to labelling) for
6.2.
o
Refrigerators, freezers and combined appliances
o
Washing machines, tumble dryers and combined appliances
o
Dishwashers
o
Ovens
o
Air conditioners
o
TV
o
Light bulbs and tubes
IMPROVEMENT WORK (BY TYPE) CARRIED OUT IN THE
DWELLING AND THE HEATING / AIR-CONDITIONING EQUIPMENT
WITH A VIEW TO IMPROVED ENERGY SAVING
Improvement work carried-out over the last year to reduce energy consumption
may be investigated. Improvement work may concern the roof and its insulation,
exterior wall insulation, windows, heating system and air conditioning equipment.
6.3.
PENETRATION OF HIGH-EFFICIENCY CONDENSING BOILERS
A condensing boiler is designed to recover energy normally discharged to the
atmosphere through the flue. This extra energy is recovered cooling the exhaust
gases so that steam condenses to liquid water, recovering the latent heat of
vaporization.
The availability of such efficient boilers in the central heating systems will be
examined.
6.4.
DIFFUSION OF HIGH EFFICIENCY BULBS
Use of Compact Fluorescent Lamps (CFL) and LED lamps in the dwelling,.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
7. ENERGY SERVICE DEMAND
This section takes as main reference the document Definition of the Household Sector,
Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH Project.
7.1.
INTENSITY OF USE OF HEATING SYSTEM AND THERMOSTAT
SET POINTS DURING THE HEATING PERIOD
Intensity of use of the central heating during the winter period (days per week,
hours per day)
Temperature the dwelling is kept during the winter months (a) during the day when
people are present (b) during the night or in the absence of people.
An operational criterion could consist in considering a simple system in which a
high temperature is set during the day when people are present, and a low
temperature is set during the day when people are absent or during the night.
More elaborate schemes may obviously be considered
7.2.
INTENSITY OF USE OF AIR-CONDITIONING SYSTEM AND
THERMOSTAT SET POINTS DURING THE COOLING PERIOD
o
Intensity of use of the central air-conditioning system during the
summer months (days per week, hours per day) and temperature at
which the dwelling is kept during the summer months (a) during the
day when people are present (b) during the night or in the absence
of people.
o
Intensity of use of the most used individual unit during the summer
period, in the case of individual units.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
8. PENETRATION OF RENEWABLE ENERGY SOURCES
This section takes as main references the document Definition of the Household Sector,
Draft version V 1.0 – 12h July 2012, by the NSi consortium involved in the MESH Project, the
American Council for an Energy-Efficient Economy, and the Energy Efficiency and
Renewable Energy web site of the U.S. Department of Energy.
This section deals with the renewable energy sources used in private dwellings in their initial
states which are externally supplied or accessed. The best way of measuring the concept
Penetration of Renewable Energy Sources is by estimating the share of the whole energy
consumption in the dwelling corresponding to renewable energies. When these energies
are produced inside the dwelling, then the relevant information about the main
equipment related to the exploitation of these sources in the dwellings must be included.
GEOTHERMAL
8.1.
If this energy source is extracted directly by the dwelling, information about heat
pumps involved must be included. Heat pumps involved in geothermal energy
may be distinguished into ground-water and water-water systems depending on
the heat source and heat sink medium.
HYDRO POWER
8.2.
Hydraulic pumps or/and and small hydraulic electric systems must be described.
SOLAR ENERGY
8.3.
The use of solar panels (area/power, by type) and the penetration of heat pumps
(type/power, electricity consumption) must be measured.
8.3.1.
Solar photovoltaic.
Solar photovoltaic panels (generating electricity via the photoelectric effect).
8.3.2.
Solar thermal.
Solar thermal panels or solar collectors are devices that, by means of an
absorber, changes solar radiation into heat which can be used for radiators,
water heating, and space heating.
Solar collectors are distinguished in vacuum, glazed and unglazed collectors.
Heat pumps may be distinguished into air-air, air-water systems depending on
the heat source and heat sink medium.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
8.4.
WIND
The use of small wind electric systems must be measured, as they are one of the
most
cost-effective
home-based
renewable
energy
systems.
Their
main
component is a wind turbine.
8.5.
SOLID BIOMASS AND BIOGAS.
These two energy sources are seldom generated inside the dwellings, though their
inputs can be produced there.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
9. ENERGY POVERTY
The scheme applied in this final section differs from the general scheme applied in this
report, due to the novelty and complexity of the concept covered. For these reasons, at a
first stage, a literary approach has been adopted, as a simpler way of explaining the
concepts and variables related to Energy Poverty, which allows extracting information
from the context in order to grasp the relevant definitions to this subject. Indeed, the task
of defining directly and accurately the concepts and variables involved in Energy Poverty
applying the format of a list, without the aid of this introduction, would have been much
more difficult regarding clarity, because of the absence of the help that a context is able
to provide. In this section the key concepts and variables related to Energy Poverty are in
bold. Finally, after this introduction, a glossary of the main concepts and variables related
to Energy Poverty is presented.
This section takes as main reference the Fuel Poverty Methodology Handbook by the
Department of Energy and Climate Change (DECC).
The term energy poverty makes reference to a lack of access to modern energy services,
and is normally limited to the household sector. From a global operational point of view,
energy poverty is defined as a lack of access to electricity and clean cooking facilities.
This is the operational concept currently adopted by the United Nations (UN), the
International Energy Agency, and other major international institutions concerned with the
issue of sustainable economic development.
The focus on electricity and on cooking facilities is due to the great impact (air pollution
inside dwellings derived from inefficient biomass combustion used for cooking, lighting or
heating purposes) that the scarcity of these two subjects make on human living conditions.
However, as far as developed countries are concerned, the term energy poverty has a
more restrictive sense, and is synonymous of fuel poverty. In these cases fuel poverty is
defined as the situation in which a household needs to spend more than 10% of its income
in fuel to maintain an adequate level of warmth. Concerning developed countries, energy
end uses different to space heating are not fundamental in the definition of fuel poverty,
because the bills corresponding to these other end uses are considered to add up to an
affordable amount of money if only basic needs for a modern life are considered.
The concept for energy poverty that is adopted in this report is that of fuel poverty recently
defined, as it is the relevant one according to the level of economic development of all
the EU countries. In addition, this concept is more demanding and more ambitious, and so
it is considered more appropriate. In what follows this report takes as main reference the
Fuel Poverty Methodology Handbook by the Department of Energy and Climate Change
of the United Kingdom (2010).
The main elements of the fuel poverty ratio may be expressed with the equation:
Fuel poverty ratio = fuel costs (usage x price)/income
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
If this ratio is greater than 0.1 then the household is Fuel Poor.
So, as it can be noticed in the previous equation, the energy efficiency of the dwelling,
the cost of energy and the household’s income are three key factors influencing the fuel
poverty ratio.
•According to this definition, first of all it must be set what an adequate level of warm is.
For this purpose in this report the recommendation of the World Health Organization will be
adopted.
An adequate level of warmth is considered to be 21 Celsius degrees in living rooms or the
main living area and 18 Celsius degrees in bedrooms or other occupied rooms. Thus, this
definition raises the issue of intensity of occupation of the dwelling. Another aspect related
to the adequate level of warmth within the ambit of fuel poverty is the length of the
heating season.
•With regard to the intensity of occupation of the dwelling, the relevant situation in relation
to fuel poverty is the case on under-occupation, because if some home is crowded it will
not significantly increase the demand for energy in order to keep an adequate level of
warmth, as far as volume or interior surface is concerned.
In this report a dwelling is considered to be under-occupied if there are both surplus
bedrooms and surplus floor area. Two issues deserve special attention regarding this
concept of under-occupation. First of all, area instead of volume is considered, in spite of
the fact that at least physically indoor volume is what must be heated in order to keep an
adequate level of warmth. But dealing with the concept of intensity of occupation, the
relationship between indoor area and number of occupants is what determines the extent
to which a dwelling is crowded. Second, both surplus bedrooms and surplus floor area are
required for a dwelling to be under-occupied; this simultaneous occurrence condition
guaranties that there is no case of crowding erroneously classified as under-occupation,
though it may underestimate the latter cases (under-occupation). The evaluation of the
under-occupation requires considering the relationship among the size of the indoor area
of the dwelling, the number of bedrooms, the number of occupants and the part and the
amount of the daily time that each of them spent indoors. This latter aspect may be
tackled in practice making some simplifying assumptions concerning full-time or part-time
job, working days, weekends and holydays, and age groups.
Turning to the definition of fuel poverty, a dwelling can in general be split into three distinct
zones: a primary heated zone (main living area), whose adequate level of warmth equals
210 C, a secondary heated zone (bedrooms and other occupied rooms), whose adequate
level of warmth equals 180 C, and an unheated zone. In case of under-occupation only a
proportion of the otherwise whole primary or/and secondary heated zone will need
heating.
•Dealing with the length of the heating season, three main aspects must be considered:
location, physical characteristics of the dwelling, and the part of the day that occupants
spent indoors. The relevant concept of location is the climate area where the dwelling is
placed. The relevant physical characteristics of the dwelling make reference to the level
40
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
of insulation provided by its structure and materials, as well as the type of dwelling
(apartment, single house…). Regarding the part of the day that occupants spent indoors,
a standard scenario assumes that the occupants are absent during normal working hours.
•As regards the concept of fuel poverty, the amount of fuel usage in the fuel poverty ratio
is theoretical by nature, as it is constrained to the theoretical concept adequate level of
warmth. In order to fix this amount of fuel usage for each household, the following
concepts shall be evaluated:
- Heat loss due to conduction from all the external house structure to the external
environment, for example heat lost through the walls or roof.
- Heat gain from solar fluxes and other gains such as from lights and appliances and
occupants.
- Heat loss due to ventilation.
- Energy required for space heating system.
- Heating regime of the inhabitants.
Hence, the valuation of fuel poverty requires modelling. As the previous list shows, the
theoretical amount of fuel usage depends mainly on energy efficiency, specific heating
system, and heating regime. At this point the energy mix usage of each household must
be considered.
•A heating regime is which achieves an adequate level of warmth according to the
following variables: external temperature to the dwelling, the gain to loss ratio (GLR), the
extent of the primary and secondary heated zones and the number of hours that the
occupants spend in these zones. It specifies whether the dwelling is under-occupied or
not, and the number of daily hours during which the dwelling is heated in working days
and weekends.
• The gain to loss ratio (GLR) measures the proportion of energy gains to energy losses,
respectively from and to the exterior of the dwelling, and depends on dwelling type,
construction and materials, applied insulation and external climate conditions.
• In order to calculate the heated volume and heat loss areas, the following variables,
among others, should be taken into account:
- Internal and external wall areas
- Roof area
- Room specific floor areas
- Habitable floor area and footprint area (the area in contact with the floor at ground floor
level)
- Perimeter of building
- Ceiling height
- Window areas
- Number of floors and rooms in a dwelling
•Once the theoretical amounts of fuels are calculated, then the relevant fuel cost is
obtained by multiplying each amount by the price of the corresponding type of fuel used
in the space heating system. This price varies among households due to factors such as
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
location, supplier and chosen tariff. The closer these prices are to the actual prices
charged to each household, the more accurate the valuation of fuel cost will be.
•Dividing the relevant fuel cost by the household’s income gives the fuel poverty ratio.
While it may be relatively easy to estimate the income of a person, doing that for a
household is much more complicated. Information provided by surveys, in addition to that
of administrative sources, is needed. So at this point having good quality specific statistics
on households’ income is essential. All sources of income must be included, and the
relevant global income estimated for the household shall be in net terms. As fuel poverty is
evaluated by means of a ratio to household’s income, taking into account the size of the
household and its composition by age or sex is not conceptually necessary, nor would it
be technically needed provided that all data to valuate the global net income of the
household are available.
•It must be pointed out that the concept of fuel poverty doesn’t vary with the cost
associated to the achievement of an adequate level of warmth. For instance, in some
regions that cost per unit of area heated will be higher than in others, due to a variety of
factors such as different climate areas or different fuel prices, among others; if the income
of the household holds constant, these differences will result in different fuel poverty ratios,
expressing that in some regions it is easier to be fuel poor than in others. However, as the
concept of fuel poverty measures economic affordability, these different situations are
perfectly comparable, and the interpretation of the ratio is not affected.
•Finally, the operational concept of fuel poverty for developed countries is naturally
expanded to include not only space heating but all the main households’ energy end
uses: space heating, space cooling, water heating, cooking, and lighting and electrical
appliances. The valuation corresponding to each end use shall reflect the appropriate
level of coverage of the basic needs associated to modern life. In this case the term
energy poverty would be more appropriate, though it is common to refer to this expanded
concept with the same name of fuel poverty. The threshold of the energy poverty ratio is
kept at 0.1 in order to report all households fuel poor as energy poor; in addition this
procedure allows classifying households that are not fuel poor as energy poor. These two
properties are desirable, as the concept of energy poverty is wider than the concept of
fuel poverty. The referential value of the energy poverty ratio is that of the fuel poverty
ratio because fuel poverty in developed countries is the most harmful component of
energy poverty.
The expanded concept of energy poverty raises some technically difficult issues. The
nature of the variables affecting an adequate level of coolness is very similar to the nature
of the variables affecting an adequate level of warmth, but the former concept is less
precise as the human body can stand with a relatively wider range of hot temperatures
than cold ones remaining healthy. On the other hand the household’s basic needs for the
end uses cooking, water heating, and lighting and electrical appliances are more directly
related to the number of occupants than the household’s basic needs for space heating,
specially the two former (cooking and water heating). Again, to derive the amounts of
fuels associated to these other four end uses in relation to the concept of energy poverty,
resorting to methods of modelling are needed.
42
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
Next, the operational list of concepts and variables related to Energy Poverty is presented.
9.1.
ENERGY POVERTY RATIO
Energy poverty ratio =energy costs (usage x price)/income
Where energy usage is that needed to cover the basic needs associated to
modern life, and income is the global income of the household in net terms.
9.2.
ENERGY POOR HOUSEHOLD
That household with an energy poverty ratio equal or greater than 0.1
9.3.
ADEQUATE LEVEL OF WARMTH
21 Celsius degrees in living rooms or the main living area and 18 Celsius degrees in
bedrooms or other occupied rooms. This concept always refers to occupied floor
surface of the dwelling.
9.4.
PRIMARY HEATED ZONE
The main living area involved in the concept of Adequate Level of Warmth.
9.5.
SECONDARY HEATED ZONE
Bedrooms and other occupies rooms apart from the main living area, involved in
the concept of Adequate Level of warmth.
9.6.
UNHEATED ZONE
The floor surface of the dwelling which is not primary or secondary heated zone.
9.7.
UNDER-OCCUPATION
A dwelling is considered to be under-occupied if there are both surplus bedrooms
and surplus floor area. If a dwelling is under-occupied then it is assumed that only a
fraction of the indoor floor area is heated.
As an operational rule, in the Fuel Poverty Methodology Handbook by the DECC it
is considered that If a dwelling is under-occupied only half of the total indoor floor
area of the dwelling is heated.
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
9.8.
SURPLUS BEDROOMS
The operational concept used in the Fuel Poverty Methodology Handbook by the
DECC states that:
A dwelling is considered to have surplus bedrooms if:
a) There are one or more extra bedrooms than required for homes without
dependent children (children under 18 years)
or
b) There are two or more extra bedrooms than required for homes with dependent
children.
9.9.
NUMBER OF BEDROOMS REQUIRED
It depends on the household constitution. The English standard states that:
a) A bedroom is required for each couple.
b) Children of different sexes below the age of 11 years can share a room.
c) Children/adolescents below the age of 21 years of the same sex can share a
room.
9.10.
SURPLUS FLOOR AREA
There is surplus floor area in a property if the floor area of the property is over
double that considered to be the “standard” living area required for the number of
occupants.
9.11.
STANDARD LIVING AREA REQUIRED FOR THE NUMBER OF
OCCUPANTS.
It attributes the extent of the living area required as a function of the number of
occupants.
9.12.
HEATING REGIME
It specifies the Heating Pattern, the Heating Extent, and the Demand for
Temperature. The demand for temperature is that required by the adequate level
of warmth.
44
OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
9.12.1.
Heating Pattern
It specifies the hours of the day during which the dwelling is heated. It depends on
the working hours of the occupants. Weekdays, Weekends and Holidays are
differentiated. If anybody is in the house in either the morning or afternoon during
weekdays, the house is assumed to require all day heating. In these cases all day
heating is assumed throughout the week. In any case, all day heating excludes a
number of hours of the day, i.e.: 8.
9.12.2.
Heating Extent
It specifies if the whole indoor floor surface of the dwelling is heated or only a
fraction of it. The latter occurs when the dwelling is under-occupied.
9.13.
LENGTH OF THE HEATING SEASON
The length of time that heating is required throughout the year. This calculation
depends on the external temperature for the degree day region for the month and
the gain to loss ratio (GLR) of the dwelling and includes consideration of solar gain.
9.14.
GAIN TO LOSS RATIO
This ratio, when referred to space heating, takes into account:
- Heat loss due to conduction from all the external house structure to the external
environment, for example heat lost through the walls or roof.
- Heat gain from solar fluxes and other gains such as from lights and appliances
and occupants.
- Heat loss due to ventilation.
9.15.
DIMENSIONS OF THE DWELLING AND, IN PARTICULAR, THE
HEATED VOLUME AND HEAT LOSS AREAS.
This set of variables includes:
- Internal & external wall areas
- Roof area
- Room specific floor areas
- Habitable floor area, and footprint area (the area of the dwelling in contact with
the ground at ground floor level).
- Perimeter of the building.
- Ceiling height
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OPERATIONAL LIST OF VARIABLES/CONCEPTS AND THEIR DEFINITIONS
- Window areas
- Number of floors and rooms in a dwelling
46