Renewable generation cannot be ramped up to meet peak demand, meaning that fossil-fuel backup capacity will still be required.

New ways to store energy are enabling larger shares of generation to be sourced from variable generation technologies like wind and solar. Despite the variability in these renewable sources of generation, it should be possible to eliminate fossil-fuel backup relatively fast.

Wind and solar generation produce electricity when the wind blows and the sun shines and cannot be steered in the same way as traditional ‘dispatchable’ resources, like fossil fuel power plants, to meet changes in power demand. To make up for their volatile output, a variety of approaches are being used to store energy from the time it is generated, to the time it is needed. This includes storing energy in hydro reservoirs, in batteries (like those used in electric vehicles), as heat (in hot water tanks distributed in homes and business) and in e-fuels (like hydrogen). By drawing on these forms of storage, as well as on consumers’ inherent ability to retime certain forms of consumption, like the running of refrigerators, the system can be made more flexible. This flexibility can be used to predict and meet the overall need for power without the need for the construction of back-up generation capacity.

The integration of variable sources of renewable generation will also be supported naturally by improving interconnection in the power system and by sector coupling. Wind speeds vary across the Continent, and as Europe’s power system becomes more interconnected surpluses in one region can be used to meet needs elsewhere, thereby alleviating the need for backup capacity. Sector coupling, meanwhile, strongly increases the access to flexible sources of demand, such as smart electric vehicle charging or price-responsive industrial demand. By combining these features of a future system with power storage technologies like hydrogen, which can be used to store and then generate power, it should be possible to entirely eliminate the need for fossil-fuel backup capacity for renewable generation.


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