Electrical energy storage

There is currently considerable interest in electrical energy storage technologies, for a variety of reasons. These include changes in the worldwide utility regulatory environment, an ever increasing reliance on electricity in industry, commerce and the home, the growth of renewable energy sources to meet the growing demand for electricity, and all combined with ever more stringent environmental requirements.

Electrical energy storage enables the decoupling of electricity generation from demand. This is of particular importance to the electricity industry since electricity demand is subject to substantial hourly, daily and seasonal variation. Also, electricity generation, particularly from renewable sources, is also subject to significant variability, both short term (over a few seconds) and longer term (e.g. hourly, daily, seasonal).

Thus, the adoption of electrical energy storage systems on utility networks is likely to result in a significant range of benefits. For example, the widespread adoption of renewable energy sources is, in many instances, constrained by the variable and intermittent nature of their output. Their appropriate integration with storage systems will allow for greater market penetration, with associated primary energy and emissions savings. Also, the environmental impact of electricity generation is heavily influenced by the operation of older and less efficient power plants, particularly for peak lopping purposes. The appropriate integration of storage in the electricity network will reduce the need for such plants, with corresponding primary energy and emissions savings. Finally, the ever-increasing reliance of society on a reliable and 'clean' electricity supply, for an increasing range of duties, is imposing ever more stringent demands on the quality of electricity supply. Storage systems can make a very valuable contribution towards satisfying such customer demands.