Wind power wasted over storage space

WIND power to supply 1.2m homes a day was wasted over winter because there is no capacity to store extra energy generated on gusty days, according to new research.

National Grid’s system operator asked turbines expected to generate 1.35 terawatt-hours (TWH) of electricity between October and January to switch off because they were not needed to meet demand at the time, according to the consultancy Stonehaven.

Meanwhile, gas-fired power turbines burned an estimated 65 TWH of gas over the period when wind speeds were lower – costing an estimated £60bn.

National Grid had asked two British coal-fired power plants to warm up in case they were needed for back-up electricity today during a cold snap. It stood them down by late yesterday afternoon.

Rupert Pearce, chief executive of electricity storage business Highview Power, which commissioned the Stonehaven analysis, said more storage capacity was needed to prevent waste.

He said: “Renewable energy storage is essential to powering a cleaner, cheaper, always-on Britain.

“By capturing and storing excess renewable energy, which is now the UK’S cheapest, most secure and most abundant form of energy, we can power Britain’s homes and businesses with renewable green energy, taking millions of tons of carbon out of the atmosphere and ending a culture of reliance on expensive foreign imports.”

Electricity supply and demand have to be constantly matched, meaning wind turbines can be paid to switch off if it is too windy, or if there is not enough capacity on cables to move the electricity to where it is needed.

Efforts are under way to develop more storage capacity. Current storage methods include lithium batteries and pumped hydro-electric storage. Highview Power is developing an alternative which uses electricity to liquify air. When power is needed, the air is turned back into gas and drives a turbine.