DePaul University
Carbon Footprint
and
Sustainability Assessment
Prepared by
Blue Planet Energy
www.BluePlanetEnergy.net
February 26, 2010
Management Summary
The following are major observations and results from the project of assessing DePaul’s carbon
footprint
•
Despite a 14% expansion in space and a 17% increase in overall enrollment, consumption
of electricity and natural gas has remained essentially constant over the past nine years.
This is attributable to the major lighting upgrade across both campuses, an ongoing
aggressive program to upgrade instrumentation and equipment, and the implementation
of energy stringent guidelines in new construction due to the LEED building process.
•
DePaul’s carbon footprint has decreased by 20% since 2001 (base year), relative to the
“business as usual” case. Along with energy improvements, increases in recycling
quantity and the purchase of renewable energy were responsible for one-third of the
decrease.
•
Continuing present operating practices in conjunction with the state mandate of a 25%
renewable portfolio standard, DePaul’s carbon footprint is projected to decrease by
almost 50% from 2001 to 2025, relative to the “business as usual” case.
•
DePaul’s students, faculty and administration have all made contributions to make the
University a more environmentally friendly campus. The administration has made its
support for environmentalism clear by donating funds to the Student Government
Association for sustainable initiatives. Students participate in classes and school and
community organizations to help promote environmental awareness and action.
•
DePaul has an impressive resume when it comes to the environment and sustainability.
However, the University needs to promote its achievements through its website and other
media.
2 Basis for Assessment and Calculations
The base year used for assessing DePaul University’s carbon footprint was calendar 2001. This
was the year for which a complete set of energy consumption data is available and it was the start
of DePaul’s concerted effort to implement efficiency measures to reduce energy consumption.
There are many different standards that can be used for assessing DePaul’s carbon footprint. The
most commonly used methodology and most widely accepted means for quantifying an
organization’s carbon footprint is the Greenhouse Gas (GHG) Protocol. The GHG protocol
divides institutional sources of greenhouse gas emissions into three different groups (referred to
as scopes). The purpose for having distinct groupings is to avoid the possibility of double
counting emissions and credits.
Scope 1 – Emissions generated from direct sources that are owned, operated or controlled by
DePaul. For accounting of GHG this includes natural gas burned for domestic heating and hot
water, cooking and laboratory operations.
Scope 2 – Emissions from indirect sources that are attributable to ongoing operations. This
includes electricity consumed at both the Loop and Lincoln Park campuses and motor fuel for
Facility Operations and Public Safety.
Scope 3 – Emission from all other indirect sources and emission credits. This includes carbon
accounting for faculty and athletic travel, recycling operations, energy efficiency measures
implemented, and purchase of Renewable Energy Certificates.
Qualitative Benefits and Positive Actions – The above three grouping are quantifications of
carbon emissions and offsets. There are, however, many other efforts DePaul is undertaking that
have beneficial effects on the environment, but are difficult to quantify. This section will explain
in some detail what is being done and how it benefits the planet.
The Future – This section deals with projections of DePaul’s environmental impact through
2025. All quantifiable inputs are assessed.
3 Scope 1 – Direct Emissions
DePaul’s direct emissions come from the burning of natural gas for facility operations. DePaul
consumes natural gas for domestic heating and hot water, cooking and laboratory operations.
Approximately 95% of all gas consumed comes from a thrid party supplier with the remainder
being supplied by the local gas utility, Peoples Gas Light & Coke.
Natural Gas Consumption
The chart to the right shows
the consumption of natural
gas (in Therms) from the
base year through 2009.
Emissions
In assessing DePaul’s carbon footprint, the consumption of the burning of natural gas has to be
converted to equivalent carbon dioxide (CO2) emissions measured in metric tonnes (MTECO2).
The chart at the right shows
the conversion of natural gas
consumption to MTECO2
(metric tonne equivalent
CO2). Note: Please see
appendix for conversion
factors and calculation
process for converting natural
gas consumption to CO2
emissions.
4 Scope 2 – Indirect Emissions
In keeping with the Greenhouse Gas Protocol, DePaul’s indirect emissions come from the
consumption of electricity and motor fuel used by Facility Operations and Public Safety.
Electricity Consumption
In our modern society electricity is used for many functions in DePaul facilities. Included are
lighting, air handling, air conditioning, heating (in some buildings) and various plug loads
ranging from sophisticated laboratory equipment to multiple student uses in dormitories.
Shown is the consumption of
electricity from 2001 (the
base year) through 2009 for
both the Loop and Lincoln
Park Campuses.
Electricity Emissions
Since 1999, DePaul has purchased 90% of its electricity from third party energy suppliers. At
that time our local electric utility (ComEd), as well as third party suppliers, started purchasing
electricity from least-cost sources. As a result, the source of electrical power is unknown to a
great degree. An acceptable method for determining the amount of carbon emission per kWh is
to use the statewide average fuel mix for the generation of electricity. (Please see appendix).
Shown to the right is the
conversion of electricity
consumption in metric tones
of CO2 emitted from the base
year through 2009.
5 Motor Fuel Consumption
Liquid motor fuel is used by Facility Operations for tractors, trucks and specific maintenance
equipment. Public Safety uses motor fuel for their fleet of patrol vehicles (including two Ford
Escape Hybrid vehicles).
The consumption of
equivalent gallons of gasoline
is shown in the following
chart.
Total Scope 2 Emissions
Scope 2 Carbon Emissions
from both electricity and
motor fuel consumption are
shown to the right.
6 Scope 3 – Emissions from Other Indirect Sources and Emission Credits
Other Indirect Sources
For DePaul other indirect emission sources include athletic and faculty travel.
Athletic Travel –Athletic travel can be separated into two modes of transportation: 1) air travel
and 2) land travel (bus, minivan, etc.) The basis used to determine which mode of transportation
utilized depends on the distance traveled (i.e., over 300 miles, the teams travel by air, less than
300 miles, they travel by land vehicles) and the number of participants (more than 12 participants
a bus is rented, fewer than 12 a van or SUV is used).
The DePaul athletic teams include:
Team
Men’s Basketball
Women’s Basketball
Men’s Soccer
Women’s Soccer
Softball
Volley Ball
Cross Country (coed)
Track & Field (coed)
Men’s Golf
Men’s Tennis
Women’s Tennis
Total Lbs CO2
Total MTECO2
# traveling
25
23
22
22
23
18
20
30
6
9
9
2007-08
154,000
170,000
80,000
70,000
235,000
60,000
25,700
145,000
32,400
55,000
30,000
1,057,100
2008-09
212,000
200,000
93,000
41,500
192,000
75,000
28,000
137,000
39,400
60,000
27,000
1,104,900
2009-10
200,000
160,000
83,000
68,000
213,500
67,500
26,200
245,000
36,400
50,000
57,000
1,206,600
479
501
547
Note: One interesting observation was that air travel generated two to three times more CO2
per participant-mile than land transportation.
Faculty Travel – Cursory data was supplied for a subset of faculty travel in 2008 and 2009. A
calculation was made and faculty travel accounts for approximately 800 tonnes per year of CO2
emissions.
Offsets for Athletic and Faculty Travel –Since the options for reducing carbon emissions from
athletic and faculty travel are limited, the most effective way to address CO2 emissions from
these sources is to invest in carbon offsets. DePaul can invest in third party offsets, such as those
from TerraPass and similar organizations, or the University can support student-run or local
environmental organizations that lead to similar reductions of carbon emissions. Total travel
emissions to be offset are approximately 1,300 tonnes per year.
7 Emission Credits and Offsets
Credits offsetting DePaul’s carbon footprint come from three sources: 1) reduced energy
consumption due to implementation of energy efficiency measures by Facility Operations; 2)
avoided energy consumption through recycling; and 3) direct purchase of Renewable Energy
Credits (RECs) and participation in Illinois’ mandated Renewable Portfolio Standard (RPS).
Efficiency Measures – DePaul has an ongoing program of upgrading mechanical, electrical and
instrumentation equipment across both campuses. In 2003 DePaul commenced an energy
efficient lighting retrofit project that upgraded all the T-12 fluorescent fixtures to energyefficient T-8 lamps and electronic ballasts. This effort was financed in large part by the Illinois
Clean Energy Trust, the City of Chicago (for the audits) and the Illinois Department of
Commerce and Economic Opportunity. Every year a portion of the utilities budget is allocated
to upgrading and replacing old boilers, pneumatic analog instrumentation and inefficient electric
motors, along with the installation of variable speed drives for air handling and chilled water
distribution. In late 2008, DePaul’s first LEED certified building came on stream. McGowan II
Science Center earned a LEED Gold designation. Implementing energy efficient measures such
as a high efficiency boiler, variable-air-volume fume hoods, outside air economizer, variable
frequency drives and high efficiency chiller resulted in a 25% (550,000 kWhs) reduction in
electrical energy and 50% reduction in natural gas consumption (115,000 therms), when
compared to similar program buildings at DePaul.
Electricity Savings (from Efficiency Measures)
The savings in electricity
consumption for energy
efficiency measures
implemented at DePaul are
shown to the right.
8 Natural Gas Savings (from Efficiency Measures)
Not all energy efficiency savings are electrical in nature; many efficiency measures reduce
natural gas consumption as well. The greatest savings in natural gas consumption come from
upgrading building automation systems, installing variable speed drives on air handlers (thereby
optimizing outside air requirements), installing more energy-efficient boilers and building better
buildings (i.e., complying with LEED certification requirements).
The savings in natural gas
consumption for
implementing energy
efficiency measures are
shown to the right.
Efficiency Carbon Offsets
The environmental benefit from the reduction in both electricity and natural gas consumption
due to the implementation of energy efficiency measures is converted to avoided metric tonne
equivalent CO2.
Shown at the right are the
carbon offsets (in MTECO2)
secured from DePaul’s
energy efficiency program.
9 Carbon Offsets from Recycling Operations
DePaul recycles aggressively on both Loop and Lincoln Park Campuses.
The quantity of waste that
has avoided being dumped
into landfills is shown in the
chart to the right.
Recycling Carbon Offsets
The environmental benefit comes from reduced transportation of materials, reduced energy
consumption for recycling metal and glass and fugitive emissions from landfills.
Shown at the right are the
equivalent offsets for
recycling at DePaul in
MTECO2
10 Renewable Energy Credits and Offsets
For their LEED Certified silver building, DePaul purchased 3,000 Renewable Energy Credits
(RECs) to be delivered over a two-year period starting in July 2007. DePaul is also participating
in Illinois’ mandated Renewable Portfolio Standard. Starting in 2008, the RPS required that 2%
of all electricity delivered be from renewable sources. This figure grew to 4% in 2009. The
assessment of carbon credits for purchasing RECs or participating in Illinois’ RPS program
results from the avoidance of purchasing electricity. Therefore, the quantification of offsets is
the same as the process used for reducing electricity consumption through implementing energy
efficiency measures.
Shown at the right are the
Renewable Energy Credits
purchased by DePaul and
DePaul’s participation in
Illinois’ Renewable Portfolio
Standard.
Shown at the right are the
carbon offsets for the
renewable energy DePaul
purchases directly and
through Illinois’ RPS.
11 Qualitative Benefits and Positive Actions
Student Government Association
DePaul’s administration has given the Student Government Association (SGA) $250,000 for the
past three years to spend on pro-environmental projects. The SGA has used this money to take
concrete steps to reduce current energy usage in many of DePaul’s buildings and departments
and also to research ways to further reduce its carbon footprint in the future. Measures taken by
the SGA in the past two years to reduce DePaul’s energy usage include:
•
•
•
•
•
•
Purchasing two 2008 Hybrid Ford Escapes for the Public Safety Department;
Adding exterior solar lighting in two key locations on the Lincoln Park Campus;
Completing the installation of CFLs in student residence halls;
Increasing the number of recycling containers around DePaul’s campus;
Installing a partial green roof system at the DePaul Center;
Upgrading building automation systems in many Lincoln Park-based buildings to
improve control of energy consumption.
During these two years, the SGA also installed a power and lighting panel circuit monitoring
system to help the Environmental Science department track student residential power
consumption. This research will result in the creation of programs that will assist students in
reducing energy usage in the residence halls.
In this coming year, SGA plans to:
•
•
•
•
Install LED fixtures at the two parking decks that are open every day and possibly use
solar power to operate the LEDs on the Sheffield deck;
Expand the DePaul Center’s green roof installation;
Continue to upgrade the building automation systems;
Add exterior recycling bins at key locations on DePaul’s campus.
Pro-environmental Steps in Transportation at DePaul
In 1999 DePaul began providing its full-time undergrad and Law students access to unlimited
rides on CTA-operated bus and rail lines through the U-Pass program. That year, the 8,000
students who qualified for the program were automatically charged a one-time fee, which
allowed them to use CTA buses and trains 24/7 during the school year, except for winter break.
Since then, the program has expanded to include full-time students in the University’s other
schools and has increased enrollment to 12,000. By the end of the 2010 school year, all the
University’s nine colleges will be participating in the program. In 2007, the University piloted a
Summer U-Pass program, which, because of strong student support, was implemented in the
12 summer of 2009. According to verbal reports from the CTA, DePaul students have averaged 1.4
million rides per year on the el, buses and subway trains. Another indication of the success of
the program is the continued decrease in sales of parking permits to students even as enrollment
has increased: 1,028 students purchased parking permits for the 2004-2005 school year, while
only 888 students purchased them for this year.
DePaul partners with the City of Chicago’s Transportation Department (CDOT) to help increase
access to and knowledge about environmentally friendly forms of transportation. During 2009
numerous events were held at DePaul promoting the use of bicycles on campus, new bike
parking facilities were installed and a bike rental service was established through the Ray Meyer
Fitness and Recreation Center. The events included Transportation Fairs and a “Car-Free
Challenge,” in which twenty faculty members and students pledged to not use their cars for a
week and find alternative modes of transportation.
In the past two years, DePaul has also taken steps to reduce its transportation carbon emissions
by purchasing more efficient vehicles for the Public Safety Department. Public Safety requires
vehicles for emergency response, escort and hospital transport services and cannot reduce the
number of vehicles in its fleet. Instead the Student Government Association used part of the
funds it received from DePaul’s administration to purchase two 2008 Hybrid Ford Escapes for
Public Safety, one of which replaced a 2003 Impala. This has resulted in a trend of gasoline
savings of 5% since their purchase.
To encourage commuting students to find more environmentally friendly ways to get to class,
DePaul has a “Commuter Information” section on its Student Life website, which includes data
on public transportation and bicycle access. The University also allows faculty, staff and
students to purchase a membership to I-GO car sharing at one-third the price of an average
membership. In addition, DePaul offers Metra assistance to some commuting students. The
program, based on financial need, gave two ten-ride tickets to 30 students in the spring of 2009.
This year, DePaul is piloting a program that will provide students with up-to-the-minute
information about bus locations. An extension of the program on the CTA’s website, DePaul’s
program will post bus schedules on screens in student buildings and, if the program is successful,
will update students by phone.
Environmental Student Groups
One of the ad-hoc committees of the Student Government Association (SGA) is the
Environmental Concerns Committee (ECC). This year, the ECC is in the process of developing
a survey to gauge environmental awareness and support for sustainable practices among
DePaul’s students. The committee is also working to establish a University “Green Fee,” that
would be added to tuition costs, and would help fund campus sustainability projects. Year
13 round, the ECC also works with the Sustainability Initiatives Committee (SIC), a faculty and
student-run organization that works to improve sustainability at DePaul. Representatives of the
ECC also sit on the Illinois Student Environmental Coalition (ISEC), which brings together
students from different colleges and universities in Illinois to advocate for environmental
awareness and action. The ISEC is currently working with No Foam Chicago to try to ban
Styrofoam in Chicago and on college campuses. To celebrate Earth Day, the ECC has planned a
numerous events, including a trip for student leaders to Allied Waste Chicago to help them learn
more about waste disposal and recycling. The ECC will also be hosting a film screening of the
environmental documentary “The 11th Hour” and will hold an Earth Day fair, bringing in
environmentally friendly vendors and organizations from the Chicago-land area to promote
environmental practices.
Environmental Actions at the Steans Center
The Steans Center for Community-based Service Learning allows students to become involved
in Chicago communities outside of the University. The Center develops long-lasting mutually
beneficial relationships with community organizations around Chicago. Students can enroll in
Service Learning classes that work with these community organizations or participate in
internships that focus on a particular Chicago neighborhood or issue. Many of the Center’s
classes and organizations focus on raising awareness of environmentalism.
Just last year, the Steans Center developed an internship to promote environmental awareness
and action. In partnership with the Gary Comer Youth Center and the Chicago Botanic Garden,
the Steans Center now offers an Environmental Stewardship Community Internship (ESCI).
ESC interns support the Gary Comer Youth Center (GCYC) in improving the Greater Grand
Crossing neighborhood’s environment through urban agriculture and youth development
projects. During their ten weeks working at the GCYC, interns will also take part in training
sessions held at the Chicago Botanic Garden. In spring 2009, the intern in the pilot program
helped the GCYC staff and young students in the Grand Crossing neighborhood harvest their
rooftop farm.
Included in the Center’s numerous community partners are organizations focusing on local
environmental justice issues, such as the Little Village Environmental Justice Organization
(LVEJO). Participating DePaul students help LVEJO and other organizations as they research
the impact of pollutants on their communities, work to improve healthy eating by, among other
things, planting local gardens, and build safe parks.
The Center also supports environmental projects undertaken by students in a variety of DePaul’s
classes. For instance, a geography class worked with a corporation based in Andersonville,
which led a certification program for local merchants to reward those taking environmentally
14 responsible actions. The Center hopes to expand this program, which resembles the LEED
certification process, to other Chicago communities. An anthropology class undertook research
to determine what would motivate the Center’s community partners to make changes that would
reduce energy usage and increase recycling. Students in a class within the Environmental
Science major tested the soil for toxicity levels in Little Village with the potential for creating
local gardens.
More Community Outreach
This year, DePaul invested $20,000 in an environmental education non-profit, Education and
Actions for Sustainable Energy Efficiency (EASEE). The organization’s mission is to empower
students (and, through them, their families and communities) to effect positive change on the
environment by educating them and giving them strategies to share their knowledge and
implement their ideas. EASEE educates high school students about energy efficiency and
renewable energy and teaches them to give presentations on these subjects to lower school
students. The program focuses on students in the Chicago Public Schools (CPS), 84% of whom
are from low-income families, as they stand the most to gain from EASEE. The founders of
EASEE believe that educating students from CPS about the environmental and economic
benefits of energy efficiency is the most efficient way to improve perceptions of environmental
action in Chicago’s communities. After learning that some of the most effective ways to save
the environment will also save their families money, the students that EASEE educates will
encourage their families to take steps to reduce their carbon footprint.
Education and Actions for Sustainable Energy Efficiency (EASEE)
EASEE’s first project is centered on the distribution of Compact Fluorescent Lamps (CFLs).
(Note: Research has shown that 40% of Chicago residents don’t use CFLs in their homes.) The
program consists of high school students fulfilling their service learning/community service
requirements by giving presentations on energy and the environment to elementary students in
grades 2 through 5. At the end of the presentation, each lower school student receives two CFLs
(one 100-Watt equivalent and one 60-Watt equivalent) to bring home to their families. The
students are taught why CFLs are beneficial, both economically and for the environment, and
take the light bulbs home with information for their families on how best to use them. Each
family will then save $150 over the lifetime of the bulbs. The initial target group is Chicago
Public Schools where 84% of the families are low income. With the money DePaul has donated,
EASEE will reach over 1,300 lower school students and families. DePaul’s donation is
environmentally equivalent to purchasing 2,000 Renewable Energy Credits, but also has the
educational benefit for the students and the economic benefit to their families.
15 The Future
Retro-Commissioning
DePaul is currently in the process of Retro-Commissioning two buildings at the Loop Campus.
Retro-commissioning is widely accepted practice of “tuning” buildings to their original
specifications with regard to operations and highlighting and implementing low-cost/no-cost
energy efficiency measures. Identified measures include:
• Addition of enthalpy control, condenser water reset and air static controls
• Installation of isolation valves on chillers
• Modification of chilled water operation to spaces that are usually unoccupied
The average simple payback for these measures is one year. The efficacy of this program from
both an economic and environmental basis is about four times greater than an energy efficient
lighting retrofit – one of the most attractive upgrades for facilities.
This effort was undertaken in conjunction with a program from the local electric distribution
company, ComEd. DePaul intends to partner with ComEd on future retro-commissioning
projects throughout both Loop and Lincoln Park Campuses.
Green Building Council LEED Certified Buildings
In late 2008, DePaul open its first LEED Gold Certified building, McGowan II Science Center.
Along with being a healthy environment for students and faculty, the building consumes
significantly less energy than buildings of similar program on campus. McGowan II uses
approximately 25% less electricity and 50% less natural gas than similar buildings. Based upon
the positive response from all stakeholders to the LEED process and result, every new building
DePaul constructs will be LEED certified.
It is expected that the combined effect of the retro-commissioning, new building LEED
certification and continuation of DePaul’s program of upgrading inefficient mechanical and
electrical equipment, will result in energy consumption staying flat even as space increases at
a 2% annual rate.
Illinois Renewable Portfolio Standard
Starting in 2008, Illinois mandated that both utilities and third party providers of electricity
purchase increasing quantities of Renewable Energy to be included in the portfolio of offerings
they sell to their respective customers. The initial requirement in 2008 was 2% of total
electricity delivered. The percentage grows every year until it reaches 25% in 2025. DePaul is
participating both financially and environmentally in Illinois’ Renewable Portfolio Standard
program. Participation has the same environmental benefit as purchasing RECs for their own
account.
16 The chart below shows two tracks:
1) Business as Usual – which assumes that DePaul continued with pre-2001 practices with
regard to energy efficiency and no additional measures taken to reduce its carbon
footprint, and
2) Projected Carbon Level – which assumes that DePaul continues with its aggressive
strategies to reduce energy consumption, resulting in flat electricity and natural gas
consumption into the future (despite a 2% annual increase in space) and offsets provided
by RECs and Illinois’ RPS.
17 Appendix
The US Environmental Protection Agency’s Clean Energy program
(http://www.epa.gov/cleanenergy/energy-resources/refs.html) was used as the framework for the
basis of the calculations in determining the equivalent carbon emissions for DePaul University.
As suggested by the program, each type of emission was checked for relevance and quantity of
equivalent carbon dioxide emissions. This was especially true determining the impact on the
environment from electricity generation. Details on fine tuning of the EPA’s calculations and
methods are shown under each emission heading, below.
Basis of Scope 1 Calculations
Therms of natural gas (from EPA’s website)
Average heat content of natural gas is 0.1 mmbtu per therm (EPA 2008). Average carbon coefficient
of natural gas is 14.47 kg carbon per million btu (EPA 2008). Fraction oxidized to CO2 is 100 percent
(IPCC 2006).
Carbon dioxide emissions per therm were determined by multiplying heat content times the carbon
coefficient times the fraction oxidized times the ratio of the molecular weight ratio of carbon dioxide to
carbon (44/12).
Note: When using this equivalency, please keep in mind that it represents the CO2 equivalency for
natural gas burned as a fuel, not natural gas released to the atmosphere. Direct methane emissions
released to the atmosphere (without burning) are about 21 times more powerful than CO2 in terms of
their warming effect on the atmosphere.
Calculation
Note: Due to rounding, performing the calculations given in the equations below may not return the exact results shown.
0.1 mmbtu/1 therm * 14.47 kg C/mmbtu * 44 g CO2/12
g C * 1 metric ton/1000 kg = 0.005 metric tons
CO2/therm
Sources
• EPA (2008). Inventory of U.S. Greenhouse Gas Emissions and Sinks:
Fast Facts 1990-2006. Conversion Factors to Energy Units (Heat
Equivalents) Heat Contents and Carbon Content Coefficients of
Various Fuel Types. U.S. Environmental Protection Agency,
18 Washington, DC. USEPA #430-F-08-005 (PDF) (2 pp, 430K, About
PDF).
• IPCC (2006). 2006 IPCC Guidelines for National Greenhouse Gas
Inventories. Intergovernmental Panel on Climate Change, Geneva,
Switzerland.
Note: We performed our own calculation for the equivalence for burning natural gas and the
0.005 metric tons CO2 per therm of natural gas is an acceptable figure.
Basis for Scope 2 Calculations
Scope 2 emissions are from indirect sources that are attributable to DePaul’s operations. This
includes CO2 emissions associated with electricity purchases and motor fuel consumed for
campus operations (Facility Operations and Public Safety).
Electricity
Since 1992 electricity on the wholesale level has been deregulated. And in Illinois, electricity
on the retail level has been restructured since 1999. As a result, the vertically integrated electric
utility was dismantled and the origin of electrical energy was not entirely known. In order to
protect rate payers, utilities could purchase electricity from least-cost sources. Therefore,
assigning a generation mix to DePaul’s sources is fraught with uncertainty. Also, adding to this
uncertainty would be how to evaluate carbon impact of the source of electricity on the margin
(that would be used when evaluating the benefit of energy efficiency improvements and
conservation). To make sense of this situation, the generation mix for the entire state of Illinois
was used for both electricity consumed and electricity saved/conserved. Based upon information
from the Energy Information Administration, for Illinois in 2007, for every 1,000 kWh of
electricity consumed 1,152 lbs. of CO2 are emitted.
Note: The figure of 1,152 lbs. of CO2 was used for both consumption and
efficiency/conservation calculations.
Gallons of gasoline consumed
To obtain the number of grams of CO2 emitted per gallon of gasoline combusted, the carbon content
of the fuel per gallon is multiplied by the oxidation factor and the ratio of CO2’s molecular weight to
that of carbon. The average carbon content of gasoline is 2,425 grams of carbon per gallon (EPA,
2005) Fraction oxidized to CO2 is 100 percent (IPCC 2006). The ratio of the molecular weight of CO2 to
carbon is 44/12.
19 Calculation
Note: Due to rounding, performing the calculations given in the equations below may not return the exact results shown.
2,425 grams C/gallon * 100% oxidation factor * 44 g
CO2/12 g C * 1 metric ton/1,000,000 g = 8.89*10-3
metric tons CO2/gallon of gasoline
Sources
• EPA (2005). Emission Facts: Average Carbon Dioxide Emissions
Resulting from Gasoline and Diesel Fuel. EPA420-F-05-001.
Available at http://www.epa.gov/oms/climate/420f05001.htm.
• IPCC (2006). 2006 IPCC Guidelines for National Greenhouse Gas
Inventories. Intergovernmental Panel on Climate Change, Geneva,
Switzerland.
Note: The above factor was used for all liquid fuel consumed by both Facility Operations and
Public Safety.
Basis for Scope 3 Calculations
Scope 3 includes other indirect sources and emission credits. Another source included is
University travel (i.e., athletic teams). Credits include credits from the implementation of energy
efficiency measures, recycling operations and the purchase of carbon offsets (i.e., Renewable
Energy Certificates).
Other Sources – DePaul University Travel
The two largest contributors of travel related CO2 emissions are Athletic Travel and Faculty
Travel.
Athlectic Travel – Athletic travel can be separated into two modes of transportation: 1) air
travel and 2) land travel (bus, minivan, etc.) The basis used to determine which mode of
transportation utilized depends on the distance traveled (i.e., over 300 miles, the teams travel by
air, less than 300 miles, they travel by land vehicles) and the number of participants (more than
12 participants a bus is rented, fewer than 12 a van or SUV is used).
In determining the carbon impact each trip for each team was evaluated. For trips by air the
amount of CO2 emitted per passenger was calculated using the Terrapass website
20 (http://www.terrapass.com/carbon-footprint-calculator/). This calculator was chosen because it
varies the amount of fuel consumed per passenger mile for each airline’s scheduled equipment.
And for trips less than 300 with more than 12 participants, bus travel was assumed. The buses
were assigned 4 mpg using diesel emitting 22.2 lbs of CO2 per gallon. The minivans and SUVs
were assigned 14 MPG using gasoline emitting 19.4 lbs of CO2 per gallon. (Both the 22.2 and
19.4 lbs of CO2 figures were from the EPA’s Clean Energy website.) The teams included:
Team
# traveling
Men’s Basketball
25
Women’s Basketball
23
Men’s Soccer
22
Women’s Soccer
22
Softball
23
Volley Ball
18
Cross Country (coed)
20
Track & Field (coed)
30
Men’s Golf
6
Men’s Tennis
9
Women’s Tennis
9
Faculty Travel --- Faculty travel is predominantly done by air with the average trip being over
1,500 miles. Unfortunately, only +/-10% of the total faculty travel was available for analysis.
Based upon our analysis for Athletic Travel, for trips over 1,000 miles, the average emission was
0.5 lbs of CO2 per passenger mile. The annual faculty air miles were calculated to be 3.4 million
miles, or 777 tonnes of CO2 emission per year.
21 Quantifying Carbon Credits and Offsets
Energy Efficiency at DePaul
Implementing energy efficiency measures can save electricity, natural gas or both. For example,
lighting upgrades predominantly save electricity while boiler upgrades save natural gas; building
automation system improvements and the installation of variable speed drives on air handling
systems can save both electricity and natural gas. The savings for each energy efficiency
measure was determined and its carbon impact was evaluated using the aforementioned factors
for electricity and natural gas. (1,077 lbs of CO2 per 1,000 kWh of electricity and 0.005 metric
tonnes of CO2 per therm of natural gas)
Purchasing Renewable Energy Credits (RECs) and Illinois’ Renewable
Portfolio Standard (RPS)
These two measures are offsets for DePaul electricity consumption. The RECs were purchased
in conjunction with the LEED certification of McGowan II Science Center and the RPS is a
compulsory Illinois program that requires electricity consumers purchase 2% Illinois-sourced
renewable energy in 2008, increasing to 25% in 2025. For each of these programs, the CO2
emissions avoided are the same as implemented energy efficiency measures (i.e., 1,077 lbs CO2
pe3r 1,000 kWh of electricity).
Recycling at DePaul
Tons of waste recycled instead of landfilled
To develop the conversion factor for recycling rather than landfilling waste, emission factors from
EPA's WAste Reduction Model (WARM) were used (EPA 2009). These emission factors were developed
following a life-cycle assessment methodology using estimation techniques developed for national
inventories of greenhouse gas (GHG) emissions. According to WARM, the net emission reduction from
recycling mixed recyclables (e.g., paper, metals, plastics), compared to a baseline in which the
materials are landfilled, is 0.81 metric tons of carbon equivalent (MTCE) per short ton. This factor was
then converted to metric tons of carbon dioxide equivalent (MTCO2E) by multiplying by 44/12, the
molecular weight ratio of carbon dioxide to carbon.
Calculation
Note: Due to rounding, performing the calculations given in the equations below may not return the exact results shown.
22 0.81 MTCE/ton * 44 g CO2/12 g C = 2.97 metric tons
CO2E/ton of waste recycled instead of landfilled
Sources
• EPA (2009). WAste Reduction Model (WARM). U.S. Environmental
Protection Agency.
[note: click "view emission/energy factors" at bottom of form to see
recycling and landfilling emission factors]
Note: For this analysis, the above figure was used for the environmental benefit of recycling
at DePaul.
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