Energy Storage

According to the Energy Storage Association, Exxon chemist Stanley Whittingham developed the concept of lithium-ion batteries in the 1970s and Sony and Asahi Kasei created the first commercial product in 1991.

The first batteries were used for consumer electronics, for instance in cell phones, and now, building on the success and proven reliability of these lithium-ion batteries, many companies have developed larger-format cells for use in energy-storage applications.  Batteries are used to store power when there is an overabundance of electricity being generated and to discharge power to the electrical grid when it is most needed.  This evolution has been made possible due to rapid advancements in battery technology based on the widespread use of cell phones, laptops and electric vehicles.

In addition to lithium-ion batteries, there are numerous other promising energy storage technologies. Flow batteries, mechanical and thermal storage, pumped hydro, and compressed air are all increasingly promising options.

Wood Mackenzie Power & Renewables projects a more than elevenfold increase in grid scale storage in the United States over the next 5 years, from 1.8 GW of installed capacity to 2020 to 21.1 GW in 2025 indicating a fundamental change in how the grid is managed. Much like the renewable energy that is driving their growth, the batteries that are used for the majority new storage systems being deployed are falling in price. This positions energy storage systems for a much broader integration into grid operations beyond renewable energy integration.  

Ravi Manghani, WoodMac’s head of storage research, noted in an interview with Greentech Media: “Over the last five years, the world began to experiment with storage; in the next five, storage will become a key grid asset.” UBS estimates that over the next decade energy storage costs will fall between 66% and 80%, and that the market will grow to as much as $426 billion worldwide. Along the way entire ecosystems will grow and develop to support a new age of battery-powered electricity, and the effects and benefits will be realized throughout society.

How does it work?

Relatively small battery cells, very similar to the small batteries used in consumer electronics, are arranged into modules, which are then arranged into racks. These racks are housed either in purpose-built containers or buildings and are connected to the grid via inverters (turning DC electricity to AC and visa versa). This allows the storage system to charge and discharge stored energy, as needed.

Is It safe?

Yes. Advances in technology and materials have greatly increased the reliability, output, and density of modern battery systems, and economies of scale have dramatically reduced the associated cost.  Safety is paramount to continued and widespread use of energy storage. In fact, all energy storage projects must incorporate sophisticated battery and energy management systems as well as operations and management protocols to monitor, alert, and report all aspects of the facilities with multiple layers of redundancy 24 hours a day, 7 days a week. Fire prevention and mitigation is of the utmost importance. Independent requirements and certifications for fire safety have undergone rapid development and implementation in recent years. Entities such as the Underwriters Laboratory and the National Fire Protection Association create these rules and guidelines which are applied to all large-scale battery products and projects. In addition, regulatory entities such as the Federal Energy Regulatory Commission and the North American Electric Reliability Corporation, as well as regional and local laws require various security measures to ensure safe and responsible operation.