Energy Storage and Installed Wind Capacity Requirements for the Substitution of Fossil Fuels in the Electricity Generation Sector

The impending adverse effects of Global Climate Change encourages the substitution of fossil fuels with non-carbon sources for electricity generation. However, while fossil fuel power plants may generate electric power at demand, the most abundant renewable energy sources–wind and solar–are intermittent or periodically variable. This necessitates the development of adequate energy storage at the utility/grid level. Using actual data for the hourly energy demand in the ERCOT electricity grid, this study examines the electricity supply-demand equilibrium and determines the necessary energy storage capacity for the substitution, first, of the coal power plants and, secondly, of all the fossil fuel power plants. The calculations show that, if the natural gas, intermediate-load power plants continue to be available, all coal units may be substituted with wind farms without the need for energy storage. When all the fossil fuel units are to be substituted, significant energy storage capacity is required, approximately 45.3 million m3. The calculations also show that the further development of nuclear energy and additional solar energy units reduce the requirements for energy storage and, also lessen the energy dissipation in the storage-recovery process.