Electricity systems already require a range of ancillary services to ensure smooth and reliable operation.
Supply and demand need to be balanced in real time to ensure supply quality (e.g., maintaining constant voltage and frequency), avoiding damage to electrical appliances and maintain supply to users.
All electricity systems require flexibility services, which allow grid operators to react to unexpected changes in demand or to the loss of large chunks of supply.
In today’s power systems, solar and wind power still have limited impact on grid operations. As the share of variable renewable energy rises, however, electricity systems will need more flexibile services through a mix of different storage technologies (highlighted the EChem storage technologies - California Hydrogen Business Council), that will allow the optimal response to the various grid stabilization requirements.