Mod_18_10 Intra Day Trading

Conference Call

Commercial Offer Data for Interconnector Units in Ending Overlap Optimisation Period (EOOP) for WD1 MSP

Software Run

29th November 2010

TW

EA1 09:30 EA2 11:30 WD1 08:00

EA1 COD EA1 MIUNs fixed

EA2 MIUNs +

EA1 MIUNs fixed

EA2 MIUNs fixed

WD1 MIUNs

+

+

LOW IMPORT PRICE LOW IMPORT PRICE HIGH IMPORT PRICE

impo

rtim

port

impo

rt

EOOP SOOP TW EOOPTW EOOP

OPTION 1zero COD

OPTION 2EA2 COD

OPTION 3persist

??

Scenario 1: Low to High Import PriceNB No system change throughout the day to load/wind/gen availability/gen COD

TW

EA1 09:30 EA2 11:30 WD1 08:00

EA1 COD EA1 MIUNs fixed

EA2 MIUNs +

EA1 MIUNs fixed

EA2 MIUNs fixed

WD1 MIUNs

+

+

HIGH IMPORT PRICE HIGH IMPORT PRICE LOW IMPORT PRICE

impo

rtim

port

impo

rt

NB No system change throughout the day to load/wind/gen availability/gen COD

EOOP SOOP TW EOOPTW EOOP

OPTION 1zero COD

OPTION 2EA2 COD

OPTION 3persist

??

Scenario 2: High to Low Import Price

• The optimisation for EOOP WD1 will influence the Interconnector flow for the last few hours of the relevant Trading Day (i.e. the end of the WD1 Trading Window).

• The outcome of the optimisation becomes the actual Interconnector flow.

• Any COD values used in the WD1 EOOP can only be a best estimate / guess, as bidding for these Trading Periods has not yet occurred.

• TSOs are concerned to minimise swings in Interconnector flow for bidding patterns that are not known. Such swings are likely to result in increases in constraint costs.

Initial Considerations

• If settlement optimisation outcomes (i.e. using actual bid values) are different from the dispatched values, this results in additional constraints.

• Once the WD1 schedule is produced, the Interconnector flow for the EOOP Trading Periods may be adjusted (if EA2 produces a lower flow than WD1, MIUNs will be adjusted in the previous Trading Day).

Impacts on Constraints

• For EA1/EA2, using the COD from the first 6 hours for the EOOP is a reasonable compromise.

• However, for WD1:

Using zero COD – is likely to produce an incorrect Interconnector schedule.

Using EA1/EA2 COD values from the start of the day – is very likely to be incorrect, as will not reflect price changes between EA2 and WD1 and may result in “artificial” swings in flow.

Persistence – reduces the likelihood of large “artificial” changes in the Interconnector flow at the end of the WD1 Trading Window.

Options