A national electricity grid must always be able to meet the needs of its users. This requires it to be: stable, maintaining the required electrical frequency (50 Hz in the UK); balanced, continuously matching supply to demand; and adequate, ensuring total generation capacity is never outstripped by demand.
Grid supply is split into three tiers: base, intermediate, and peak load. Baseload is a permanent minimum amount of electricity that is required at all times and is met by predictable, long-running power sources, usually coal-fired plants. Intermediate power plants are more flexible and can vary output to suit the needs of the grid, but at a cost to the system operator. These include nuclear, hydroelectric and gas/diesel combined cycle turbine plants. Finally, peak power generators are called upon to meet short-term spikes of requirement and as such must be able to start up and provide power instantaneously.
This information sheet explains the key benefits that fuel cells can offer in this application, the fuel cell types used in the application today, and a case study of South Korea’s Renewable Portfolio Standard.