Some renewable energy, such as electricity generated by wind turbines, is produced in an unpredictable and intermittent cycle, when the wind blows. This energy supply does not always match the energy demands, and therefore, very often wind turbines are turned down (this is called wind curtailment).
In times when there is a peak in electricity demand, grid operators will ramp up fossil fuel power plants to ensure the electricity supply, but these cause substantial emissions.
The ability to store underground large amounts of hydrogen generated by rapid response electrolysers, provides the necessary means for both capturing surplus renewable energy and generating peak power without causing emissions when there’s a deficit in renewable energy.
The associated storage capacity far exceeds that achievable via conventional methods (e.g. pumped storage and batteries) and so geological hydrogen storage is the key option for buffering our future energy system.