LLF Methodology Statement EHV and HV Definitions
Background
In December 2010, the Authority directed changes to the Standard Licence Conditions (SLC) definitions of the
Common Distribution Charging Methodology (CDCM) and Extra High Voltage Distribution Charging Methodology
(EDCM).
Balancing and Settlement Code (BSC) Change Proposal 1343 was subsequently raised and implemented to ensure
that the treatment of line losses for High Voltage (HV) and Extra High Voltage (EHV) sites remains the same
irrespective of changes in the DCUSA. To achieve this, Balancing and Settlement Code Procedure (BSCP)128 was
amended such that LSDOs must define EHV and HV in their Line Loss Factor Methodology Statements, rather than
the definition being connected to the distribution licence.
The first set of Line Loss Factor Methodology Statements produced after the implementation of CP1343 were
presented to the Supplier Volume Allocation Group (SVG) for approval at its meeting on 31 August 2011.
The Supplier Volume Allocation Group Concerns
At this meeting, the SVG approved each of the Line Loss Factor Methodology Statements. However, it noted that
each LDSO has defined High Voltage and Extra High Voltage differently (a list of these definitions can be found in
Appendix 1).
The SVG expressed concerns about the impact that these differences may have on competition and the additional
complexity that it adds to the market. The group asked that ELEXON raise the possibility of introducing a
standardised EHV and HV definition at the Distribution Charging Methodology Forum.
Next Steps
DCMF members are invited to share their views on the Line Loss Factor Methodology Statement definitions of EHV
and HV and comment on whether a standardised definition of EHV and HV should be introduced. The feedback
received will be presented to the SVG.
22 November 2011
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© ELEXON 2011
Appendix 1: Approved LLF Methodology Statement definitions of EHV and HV
Name of
Distribution
Business
Northern Powergrid
(Northern Electric
Distribution
Limited) &
(Yorkshire
Electricity
Distribution plc)
UK Power
Networks
Operating
in GSP
Groups
Northern,
Yorkshire
EHV and HV Definition
EHV - Premises or distribution systems metered at nominal voltages at or
above 22 kilovolts (22kV); or Premises or distribution systems metered at
below 22 kilovolts (22kV) but connected to a dedicated, non-distributing,
primary substation with transformers having ratios of 132/66/33kV to the
metered voltage.
HV - premises or Distribution Systems metered at nominal voltages of less
than 22 Kilovolts (22kV), but greater than 1 kilovolt (1KV) excluding any site
defined as EHV.
Eastern,
London,
South
Eastern
EHV - A nominal voltage of 22,000 volts or above, or for the purposes of this
LLF methodology a customer connected site to a substation with a primary
voltage of 66,000 Volts or above. In practice, this means sites with exit
points at 132 kV, 33 kV, and 25 kV or at a 132/11 & 132/6.6 kV substation.
HV - A nominal voltage greater than 1000 volts and less than 22,000 volts,
excluding any site defined as EHV.
Electricity North
West Limited
North
Western
EHV - Premises or distribution systems metered at nominal voltages of 22kV
or above.
HV - Premises or distribution systems metered at nominal voltages of less
than 22kV, but greater than 1kV excluding any site defined as EHV.
Scottish Power
Southern Electric
Power Distribution
plc
Merseyside
and North
Wales, South
Scotland
EHV connection is defined as a connection to the network at a nominal
voltage of 22kV or above.
Southern
EHV - Nominal voltages of 22kV.and above. In practise, this means sites with
exit points at 132 kV, 66 kV, 33 kV and 22 kV or at a 132/33 kV, 132/11 kV,
66/22 kV or 66/11 kV substation.
HV connection is defined as a connection to the network at a nominal
voltage of greater than 1kV and less than 22kV.
HV - Nominal voltages of greater than 1kV and less than 22kV excluding any
site defined as EHV.
Scottish Hydro
Electric Power
Distribution plc
North
Scotland
Western Power
Distribution
East
Midlands,
Midlands,
South Wales,
South
Western
EHV - Nominal voltages of 22kV and above. In practise, this means sites with
exit points at 33 kV and BSP/11 kV.
HV - Nominal voltages of greater than 1kV and less than 22kV excluding any
site defined as EHV.
Extra High Voltage (EHV) applies to premises or distribution systems
metered at nominal voltages of 22kV and above. Those sites connected at
the 11kV bus bars of a primary substation whose primary voltage is 132kV or
66kV will be regarded as EHV for the purposes of this methodology.
High Voltage (HV) applies to premises or distribution systems metered at
nominal voltages of at least 1kV and less than 22kV excluding any site
defined as EHV.
22 November 2011
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© ELEXON 2011