Tariff Information Paper
Draft Annual Load
Factors for 2014/15
Generation TNUoS
Charges Under
CMP213 (Project
TransmiT)
This information paper contains draft Annual Load Factors
(ALFs) that National Grid proposes to use in the calculation of
Generation TNUoS charges for 2014/15 if Directed to
implement CMP213 WACM2. We welcome customer queries
in regards to these by 17 January 2014.
13 December 2013
V1.0
Disclaimer
This report is published without prejudice and whilst every effort has been made to ensure the accuracy of the Draft Annual Load
Factors, National Grid reserves the right to alter individual Final Annual Load Factors following discussion with the affected generators.
Contents
1
Introduction .....................................................................................3
2
Changes from Indicative Annual Load Factors.............................4 Contact:
3
Specific Annual Load Factors ........................................................5
4
Generic Annual Load Factors.........................................................8
5
Next Steps........................................................................................9 Stuart.Boyle@
6
Comments & Feedback.................................................................10
Any Questions?
Stuart Boyle
nationalgrid.com
Appendix A – Calculation of Specific Annual Load Factors .............11
Appendix B – Calculation of Generic Annual Load Factors..............15
01926 655588
2
1
Introduction
CMP213 is the CUSC Modification proposal following on from Project TransmiT, the
Authority’s review of electricity transmission charging and associated connection
arrangements. Further details of the modification can be found on the CUSC
Modifications area of National Grid’s website1.
CMP213 seeks to make changes to the Transmission Network Use of System
(TNUoS) charging methodology, in three areas. One of these is to better reflect the
costs imposed by different generators on the electricity transmission network. Ofgem
indicated on 1 August 2013 that it was minded to approve CMP213 Working Group
Alternative 2 (WACM2) which proposed to use specific generator Annual Load Factors
(ALFs) to reflect the costs imposed by different generators on the electricity
transmission network. Under this proposal the wider generation charge is comprised of
four tariff components; Peak Security, Shared Year Round, Non-Shared Year Round
and Residual. The Shared Year Round component of a generator’s TNUoS charge is
the product of the Shared Year Round tariff component for the generation zone,
Transmission Entry Capacity (TEC) and the specific ALF of the generator.
CMP213 WACM22 requires National Grid to provide its customers with draft ALFs for
the following charging year before 25th December. If a Direction is given to implement
CMP213 with effect from 1 April 2014 then we intend to use the draft ALFs stated in
this document for the purposes of charge setting. Under CMP213 WACM2 customers
have a period of 15 working days from the date of publishing to notify National Grid of
any errors. Given Ofgem’s minded to position to implement WACM2 from April 2014,
and customers’ need for information on the impact on their charges, we are publishing
these draft ALFs in advance of the requirements. We believe that this will allow our
customers more opportunity to understand and review their specific ALFs and we are
happy to provide support and advice on their derivation on a bilateral basis. To that
end, this document also describes how these draft ALFs have been calculated.
We encourage customers to review the draft ALFs pertaining to their operations and
welcome any comments before 17 January 2014. If a Direction is given to implement
CMP213 in April 2014 the final ALFs will be published in late January 2014.
1
http://www.nationalgrid.com/uk/Electricity/Codes/systemcode/amendments/currentamendment
proposals/
2
http://www.nationalgrid.com/NR/rdonlyres/70C7A64A-A62C-418D-A72A-
FF87CEE869FA/61007/FinalReportVolume4v10FinalReport.pdf
3
2
Changes from Indicative Annual Load Factors
On 4 November 2013, we published our quarterly update of forecast TNUoS tariffs for
2014/153. Appendix G to that document contained indicative generic and specific
ALFs. These were intended to provide customers with an early view of their specific
ALFs to help their understanding of the impact of CMP213 WACM2. Since then we
have further audited the data and process used for ALF calculation and as a result
these draft ALFs may differ from the November indicative values.
Commissioning dates have generally been taken from the Digest of United Kingdom
Energy Statistics 2013 Table 5.114. However, commissioning dates within the five
charging years under consideration (2008/9 to 2012/13) have been checked against
Metered Output and Final Position Notification data to determine the exact
commissioning date.
Since November there have been a number of changes to the generation background.
Appropriate changes have been made to the table of specific draft ALFs.
Consequently, there are no longer any biomass power stations commissioning in this
period and so the generic ALF for this technology has been removed.
3
http://www2.nationalgrid.com/WorkArea/DownloadAsset.aspx?id=24906
4
https://www.gov.uk/government/publications/electricity-chapter-5-digest-of-united-kingdom-
energy-statistics-dukes
4
3
Specific Draft Annual Load Factors
Table 1 shows specific draft ALFs for each power station expected to incur Generator
Transmission Network Use of System Charges during 2014/15. The methodology
used to calculate these is summarised in Appendix A.
Table 1
Power Station
Aberthaw
Achruach Wind Farm
Aigas
An Suidhe Wind Farm
Arecleoch
Baglan Bay
Barking
Barrow Offshore Wind Farm
Barry Power Station
Black Law
Brigg
Enfield
Carraig Gheal Wind Farm
Carrington Power Station
Clunie
Clyde (North)
Clyde (South)
Connahs Quay
Corby
Coryton
Cottam
CDCL
Cowes
Cruachan
Crystal Rig 2
Culligran
Damhead Creek
Deanie
Deeside
Dersalloch
Didcot B
Dinorwig
Drax
Dungeness B
Dunlaw Extension
Edinbane Wind
Ewe Hill
Eggborough
Errochty
Fallago
Farr Wind Farm, Tomatin
Fasnakyle
Fawley
Specific ALF
49.8011%
34.3151%
28.8524%
31.1243%
31.5330%
42.9466%
51.5494%
42.8802%
24.9253%
23.5301%
16.8962%
58.4627%
32.8076%
63.1254%
34.8904%
26.9795%
22.6957%
49.7752%
22.8437%
64.4106%
61.8678%
60.7867%
0.2184%
12.8457%
39.3191%
28.8524%
80.4315%
28.8524%
51.7370%
34.3151%
60.7220%
15.5970%
80.6044%
37.3658%
34.9285%
37.0971%
34.3151%
44.5431%
16.9493%
33.8663%
34.9986%
27.9503%
0.3473%
5
Power Station
Fawley CHP
Ferrybridge
Ffestiniog
Fiddlers Ferry
Finlarig
Foyers
Glendoe
Glenmoriston
Gordonbush Wind
Grain
BP Grangemouth
Great Yarmouth
Greater Gabbard Offshore Wind Farm
Griffin Wind Farm
Gunfleet Sands Offshore Wind Farm
Gunfleet Sands II Offshore Wind Farm
Gwynt Y Mor Offshore Wind Farm
Hadyard Hill
Harestanes
Hartlepool
Heysham Power Station
Hinkley Point B
Humber Gateway Offshore Wind Farm
Hunterston
Immingham
Indian Queens
Invergarry
Ironbridge
Keadby
Kilbraur
Killingholme 2 (Centrica)
Killingholme (Eon)
Kilmorack
Langage
Lincs Offshore Wind Farm
Little Barford
Littlebrook
Lochay
Lochluichart
London Array
Longannet
Luichart
Marchwood
Mark Hill Wind Farm
Medway Power Station
Millennium Wind
Mossford
Nant
Ormonde Offshore Wind Farm
Orrin
Pembroke Power Station
Specific ALF
67.7940%
39.1076%
3.3999%
45.2317%
48.4286%
16.4781%
8.6721%
39.8364%
34.5574%
17.0656%
62.5601%
62.8454%
29.0801%
22.0106%
38.5634%
36.9738%
27.2330%
28.6374%
34.3151%
75.8457%
74.5820%
56.2027%
38.7844%
71.9543%
61.1425%
1.3465%
48.2159%
13.3327%
58.7586%
42.0061%
25.3258%
32.0424%
28.8524%
58.9046%
31.4268%
52.4152%
0.3172%
36.7481%
34.3151%
36.8234%
47.4635%
49.5378%
70.3361%
29.7583%
38.5007%
42.3973%
49.5378%
24.2229%
41.1574%
49.5378%
57.2218%
6
Power Station
Peterborough
Peterhead
Quoich
Ratcliffe on Soar
Robin Rigg East
Robin Rigg West
Rocksavage
Rugeley
Rye House
Saltend
Seabank
Sellafield
Severn Power
Sheringham Shoal Offshore Windfarm
Shoreham
Sizewell B
Sloy
South Humberbank
Spalding
Staythorpe C
Sutton Bridge
Taylors Lane
Thanet Offshore Windfarm
Toddleburn Wind Farm
Torness
Walney I Offshore Wind Farm
Walney II Offshore Wind Farm
West Burton A
West Burton B
West of Duddon Sands Offshore Wind Farm
Westermost Rough
Whitelee
Whitelee Extension
Wilton
Wylfa
Specific ALF
15.3462%
57.9351%
48.2159%
57.4270%
35.9220%
36.8231%
47.7745%
52.6785%
42.7532%
89.7591%
55.4754%
22.0714%
39.1019%
30.4724%
69.0820%
85.1800%
10.3498%
57.0565%
65.6849%
54.7260%
60.4887%
0.2514%
35.1276%
33.2962%
85.8904%
40.4477%
39.7298%
49.0530%
50.2665%
38.7844%
38.7844%
26.9403%
23.7021%
25.4458%
72.3843%
7
4
Generic Draft Annual Load Factors
Generation technologies and associated generic draft ALFs are shown in Table 2.
The methodology for calculating these is summarised in Appendix B. Generic draft
ALFs have been used to set specific draft ALFs for power stations with no or limited
historical data, including power stations commissioning during 2013/14 and 2014/15.
Table 2
Technology
Oil_and_OCGT
Pumped_Storage
Hydro
Onshore_Wind
Offshore_Wind
Coal
CCGT_and_CHP
Nuclear
Generic ALF
0.5941%
12.0802%
33.2711%
34.3151%
38.7844%
42.9017%
63.1254%
67.9035%
Intermittent/
Conventional
Conventional
Conventional
Conventional
Intermittent
Intermittent
Conventional
Conventional
Conventional
8
Carbon/Low
Carbon
Carbon
Carbon
Low Carbon
Low Carbon
Low Carbon
Carbon
Carbon
Low Carbon
5
Next Steps
Draft TNUoS tariffs for 2014/15 will be published by 25 December 2013. If direction
is given to implement CMP213 with effect from 1 April 2014 then we propose to use
the ALFs stated in this document, accounting for any changes resulting through
subsequent bi-lateral discussions with customers, to set TNUoS charges for 2014/15.
To that end, where customers have a query regarding their specific ALFs they are
requested to contact National Grid as soon as possible and by 17 January 2014 at the
latest.
Final tariffs for 2014/15 will be published at the end of January 2014. If direction is
given to implement CMP213 with effect from 1 April 2014 then the final ALFs used to
set charges will be published at the same time.
6
Comments & Feedback
Comments & Feedback
As part of our commitment to customers National Grid welcomes comments and
feedback on the information contained in this statement. In particular, to ensure that
information is provided and presented in a way that is of most use to customers, we
would welcome specific feedback on:
The level of numeric detail provided to explain the load factors;
The quality of the explanation given;
Information that is not useful and could be omitted; and
Information that is missing that could be added.
These should be sent to:
Damian Clough
[email protected]
National Grid
Warwick Technology Park
Warwick
CV34 6DA
01926 656416
10
Appendix A – Calculation of Specific Annual Load Factors
ALFs have been calculated for each generator using historical Transmission Entry
Capacity (TEC), Metered Flows (MF) and Final Position Notifications (FPN) from the
five most recent complete charging years, i.e. 2008/9 to 2012/13 inclusive. No
historical or forecast data for 2013/14 has been used.
ALFs are calculated at power station level. Therefore for a power station with multiple
Balancing Mechanism Units (BMU) representing generating sets and station demand,
the BMU are aggregated before calculating the ALF.
Cascade hydro schemes may have multiple power stations included in a BMU. For
these the ALF is calculated at scheme level by aggregating stations and their
associated BMU before calculating the ALF. The scheme level ALF is applied to each
station in the scheme.
There are 17,520 half hour periods in a charging year (17,568 for 2011/12 due to the
leap year). In each half hour the metered flow (MF) and Final Position Notification
(FPN) of the generator are compared and the higher of the two used. If both MF and
FPN are negative, i.e. the station has net demand then zero is used. The ‘higher of’ is
summated over all the half hours in the charging year to give the numerator for that
charging year in kWh.
The denominator for a charging year is the sum of the Transmission Entry Capacity
(TEC) in each half hour divided by two to give kWh consistent with the numerator.
TEC is contracted on a daily basis so each half hour of a day has the same TEC and
changes in TEC take place at midnight.
The load factor for a year is the numerator divided by the denominator. A load factor
is calculated for each charging year. This is summarised in the following diagram.
< - - - - - - - - - - Charging Years used to set ALF - - - - - - - - - - >
2008/09
2009/10
2010/11
2011/12
2012/13
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17568HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
÷
÷
÷
÷
÷
Sum TEC/2
over
17520HH
Sum TEC/2
over
17520HH
Sum TEC/2
over
17520HH
Sum TEC/2
over
17568HH
Sum TEC/2
over
17520HH
=
=
=
=
=
2008/09
ALF
2009/10
ALF
2010/11
ALF
2011/12
ALF
2012/13
ALF
11
ALF Calc.
(Now)
ALF
Applicable
2013/14
2014/15
Where there are five complete charging years of data the two years with highest and
lowest load factor are excluded and the ALF is the average of the remaining three
years. In the following example the highest ALF was in 2008/9 and the lowest ALF in
2010/11 but in practice they could be any of the five years and will vary by Station or
Hydro Scheme.
< - - - - - - - - - - Charging Years used to set ALF - - - - - - - - - - >
{
2008/09
2009/10
2010/11
2011/12
2012/13
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17568HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
÷
÷
÷
÷
÷
Sum TEC/2
over
17520HH
Sum TEC/2
over
17520HH
Sum TEC/2
over
17520HH
Sum TEC/2
over
17568HH
Sum TEC/2
over
17520HH
=
=
=
=
=
2008/09
ALF
2009/10
ALF
2010/11
ALF
2011/12
ALF
2012/13
ALF
Highest
ALF Calc.
(Now)
ALF
Applicable
2013/14
2014/15
}
ALF = Average of
remaining three
Lowest
Where there are only four complete charging years of data, the year with the lowest
load factor is excluded and the ALF is the average of the remaining three years.
< - - - - - - - - - - Charging Years used to set ALF - - - - - - - - - - >
2008/09
{
2009/10
2010/11
2011/12
2012/13
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17568HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
÷
÷
÷
÷
Sum TEC/2
over
17520HH
Sum TEC/2
over
17520HH
Sum TEC/2
over
17568HH
Sum TEC/2
over
17520HH
=
=
=
=
2009/10
ALF
2010/11
ALF
2011/12
ALF
2012/13
ALF
Lowest
12
ALF Calc.
(Now)
ALF
Applicable
2013/14
2014/15
}
ALF = Average of
remaining three
Where there are three complete charging years of data the ALF is the average load
factor of those three years.
< - - - - - - - - - - Charging Years used to set ALF - - - - - - - - - - >
2008/09
{
2009/10
2010/11
2011/12
2012/13
Max
(Metered,
FPN, 0)
summed
over
17520HH
Max
(Metered,
FPN, 0)
summed
over
17568HH
Max
(Metered,
FPN, 0)
summed
over
17520HH
÷
÷
÷
Sum TEC/2
over
17520HH
Sum TEC/2
over
17568HH
Sum TEC/2
over
17520HH
=
=
=
2010/11
ALF
2011/12
ALF
2012/13
ALF
13
ALF Calc.
(Now)
ALF
Applicable
2013/14
2014/15
}
ALF = Average of three
Where there are less than three complete charging years of data the ALF is the
average of three years load factors calculated as follows:
•
For complete years of data the load factor is calculated as above.
•
For years with no data the generic load factor for the station’s technology type is
used.
•
For years during which a power station commissioned or decommissioned, a
partial year load factor is calculated for the period the station was commissioned
and a generic load factor used for the remainder. The load factor for that year is
then the average of the partial and generic load factors weighted by the number of
half hours.
Partial Year
Full Year
ALF Calc.
(Now)
ALF
Applicable
2010/11
2011/12
2012/13
2013/14
2014/15
Generic ALF
Generic
ALF
Max
(Metered,
FPN, 0)
summed
over avail.
HH
Max (Metered, FPN, 0)
summed over
17520HH
÷
÷
Sum TEC/2
over avail.
HH
Sum TEC/2 over
17520HH
=
=
2011/12
Partial ALF
2012/13 ALF
}
ALF = Average of three
{
{
No data
Weighted by
number of HH
Where a customer demonstrates that the power station has been repowered with a
different technology, data prior to the re-powering relates to the old technology and
may be discarded. Where this leaves less than three years of data available the
generic load factor for the new technology will be used prior to the re-powering.
14
Appendix B – Calculation of Generic Annual Load Factors
Generic ALFs are the average of the ten most recently commissioned power stations
of that type with five complete charging years of data. Where less than ten power
stations meet this requirement other stations with four or less years of data have been
included.
Where stations share the same commissioning year and have the same number of
years’ data then they have all been included in the calculation, i.e. more than ten
stations included.
Power station plant types have been identified using the Digest of United Kingdom
Energy Statistics 2013 Table 5.11 from the Department of Energy & Climate Change
website5.
5
https://www.gov.uk/government/publications/electricity-chapter-5-digest-of-united-kingdom-
energy-statistics-dukes
15