Energy data analysts, EnAppSys, says that the ability of power generators to respond to demand is a more crucial component to combating potential power blackouts than adding extra capacity.

Paul Verrill, Director at EnAppSys, told Power Engineering International about the considerations surrounding the costs of preventing future supply blackouts and shortages from the country’s power generation sector.
Paul Verill
Verrill said while most people are focusing on the tight capacity margin between supply and demand, the real threat could come from generators in the market being unable to response within the required window to balance the instantaneous supply-demand position.

“Where margin does exist within the market, much of that margin can be sat idle and cold, requiring anywhere from between 1 and 6 hours to warm up and start. With an increasing amount of renewables on the system and with an increasing reliance on interconnectors, a blackout in the UK is more likely to come about not due to a lack of capacity, but due to a lack of capacity able to deliver additional power within the required timeframe.”

For over 12 months, EnAppSys has been monitoring grid frequency and analysing large deviations; which if not managed can lead to instability and the lights going out. Verrill says they have seen ‘numerous events’ where unexpected deviations in wind or unexpected losses of interconnector volumes have required some rapid intervention using pumped storage assets.

“We anticipate this need will become more acute as the amount of gas and coal generation online at any one time is reduced as a result of displacement by renewables and new interconnector capacity.”

“The solution to this problem lies in fast response energy storage, fast response demand side management, spinning reserve and potentially new grid frequency regulation equipment/ plants.”

Verrill also provided an insight into the true nature of the capacity margin. He said the closures of coal-fired power facilities such as Longannet are understandable given the fact that the margin, while tight over the winter, ‘the market does not need these plants 99 per cent of the time and within the current structure does not want to pay for them’.

“Ultimately the consumer pays the price to keep the lights on and there has been no debate yet as to what the cost is before this becomes too expensive. More capacity would result in greater security of supply, but at the cost of higher bills and as a whole consumers need.”

To read a longer version of EnAppSys analysis view here