Energy Storage for Power Systems

Unregulated distributed energy sources such as solar roofs and windmills and electric vehicle requirements for intermittent battery charging are variable sources either of electricity generation or demand. These sources impose additional intermittent load on conventional electric power systems. As a result thermal power plants whose generation is absolutely essential for any power system are increasingly being used for cycling operations thus increasing greenhouse gas emissions and electricity cost. The use of secondary energy storage might be a solution. Various technologies for storing electric energy are available; besides electrochemical ones such as batteries, there are mechanical, chemical and thermal means, all with their own advantages and disadvantages regarding scale, efficiency, cost, and other parameters.