Underground revolution: hydrogen storage for flexible generation

Over the next few decades, the way that electricity is generated in the UK is predicted to change considerably. Nuclear power stations will make a larger contribution to the total generating capacity, and fossil fuel stations will increasingly be built or retrofitted with equipment to capture their carbon dioxide emissions so that they can be compressed and stored, most likely in offshore repositories below the sea bed.

Meanwhile, more renewable generating capacity, based around wind farms and tidal generation and possibly wave power, will be coming on stream from sites around the UK’s coast.

This represents a problem. Nuclear power is inflexible — reactors work best when producing a stable amount of thermal energy throughout the day, which has to be fed to the boilers to raise steam. Similarly, although conventional fossil-fuelled turbines can be operated flexibly, the addition of CCS technology again means that they are best run at as near a constant rate as possible.