Prospects for Large-Scale Energy Storage in Decarbonised Power Grids

The International Energy Agency (IEA), an autonomous agency, was established in November 1974. Its mandate is twofold: to promote energy security amongst its member countries through collective response to physical disruptions in oil supply and to advise member countries on sound energy policy. The IEA carries out a comprehensive programme of energy cooperation among 28 advanced economies, each of which is obliged to hold oil stocks equivalent to 90 days of its net imports. The Agency aims to: n Secure member countries' access to reliable and ample supplies of all forms of energy; in particular, through maintaining effective emergency response capabilities in case of oil supply disruptions. n Promote sustainable energy policies that spur economic growth and environmental protection in a global context – particularly in terms of reducing greenhouse-gas emissions that contribute to climate change. n Improve transparency of international markets through collection and analysis of energy data. n Support global collaboration on energy technology to secure future energy supplies and mitigate their environmental impact, including through improved energy efficiency and development and deployment of low-carbon technologies. n Find solutions to global energy challenges through engagement and dialogue with non-member countries, industry, international organisations and other stakeholders. The European Commission also participates in the work of the IEA. Please note that this publication is subject to specific restrictions that limit its use and distribution. The terms and conditions are available online at www.iea.org/about/copyright.asp This paper focuses on the potential role that large-scale energy storage systems can play in future power systems. The starting point and basis for simulations is the Energy Technology Perspectives 2008 (ETP) BLUE scenario for power supply (IEA, 2008). According to the scenario, increased use of renewable energy and nuclear technologies can play an important role in reducing CO 2 emissions dramatically in the power sector. Through the increased use of these technologies, the use of fossil fuel powered plants, and consequent CO 2 emissions, will be reduced. Wind power and solar power provides 12% and 11% of global electricity generation by 2050 in the BLUE Map scenario. Variable output renewable technologies such as wind and solar are not dispatchable. With large shares of these technologies, steps would need to be taken to ensure the continued reliable supply of electricity. While related issues include voltage and frequency variations, inter alia, this report focuses on frequency stability. Constant balance of demand and supply is essential to achieve …