Energy Storage: Information on Challenges to Deployment for Electricity Grid Operations and Efforts to Address Them, Report to Congressional Requesters

摘要

Power plants' electricity output must be matched continuously with demand, which varies depending on the time of day and year. To maintain a reliable supply of electricity, operators of the electricity grid--a complex network of power plants and power lines managed by utility companies and other operators--take steps to ensure power plants are available to generate electricity when needed. Increasingly, renewable sources of energy, such as solar and wind, are being integrated into the grid. Energy storage allows for electricity to be stored and used later when it is needed and could change the operating capabilities of the electricity grid. Batteries and other energy storage technologies can store energy in one form--such as chemical, mechanical, or thermal energy--and transform that energy to generate electrical power at a later time. GAO [Government Accountability Office] was asked to provide information on the role of energy storage in grid operations. This report describes (1) how energy storage can be used to enhance grid operations and performance; (2) factors that affect the deployment of energy storage for grid operations; and (3) federal and state policies and other efforts that address the deployment of energy storage. GAO reviewed studies published from 2012 through 2017; and interviewed 41 stakeholders, including officials from government agencies and representatives of industry and other groups based on their knowledge of energy storage and grid operations.