As of July 2012, the total installed capacity of the world’s energy storage system calculated by the Energy Storage Commission is 605MW, of which the percentage of installed capacity of various technologies is shown in Figure 1, and the distribution in various countries is shown in Figure 2 (as of July 2012, the statistical energy storage projects do not include pumped water storage, compressed air energy storage, and heat storage).
As can be seen from Figure 1, the current energy storage systems with more than half of the world’s installed capacity are sodium-sulfur batteries, followed by lithium-ion batteries and lead storage batteries. It can be seen from Figure 2 that Japan and the United States are the countries with the largest installed capacity of energy storage in the world.
After the Fukushima earthquake, the Japanese power grid encountered many problems. Before the earthquake, the Japanese power grid was one of the most reliable in the world. The Japanese government attaches great importance to the energy storage industry and household photovoltaic power generation systems. It is estimated that by 2030, more than half of Japanese households will use rooftop photovoltaic/energy storage systems.
At present, the total scale of Japan’s energy storage accounts for 15% of the total scale of the power grid, of which the total scale of pumped storage is 25.5GW. In addition to pumped storage, the energy storage technologies adopted in Japan mainly include sodium-sulfur battery technology, vanadium flow battery technology, and lithium-ion battery technology. Among them, about 300MW of sodium-sulfur battery energy storage projects are mainly used in fields such as peak shifting, load balancing, and renewable energy integration.
Since 2012, Japan’s Panasonic Corporation has joined forces with eight other companies to start the construction of Japan’s first smart and environmentally friendly city in Fujisawa City, Kanagawa Prefecture. It plans to provide standard solar power generation systems, household fuel cells, and energy-saving appliances for each house, and use smart electrical management systems to achieve the best energy efficiency. At present, many Japanese companies have devoted themselves to the development of household energy management systems, and have successively carried out many small-scale demonstration or test projects.
Compared with the power grids in Japan and Europe, the U.S. power grid is outdated and inefficient. Similar to the Chinese power grid, the transmission and distribution losses are about 6%. This prompted the United States to invest a lot of money in the field of smart grids. So far, the United States has invested 185 million U.S. dollars in energy storage projects. If the loan guarantee research, development grants, and new project grants are taken into account, the total investment will exceed 700 million U.S. dollars. These funds directly stimulated the development of the US energy storage market, making the US a world leader in the development of new technologies.In addition to pumped water storage and compressed air energy storage, the technology used in US energy storage projects was mainly lead-acid battery technology before 2000, and after 2000, lithium ion battery ups technology began to dominate, and advanced lead-acid batteries, flywheel energy storage technology, and some flow battery technologies were also applied. At present, the total installed capacity of pumped storage in the United States is 22GW; the large-scale compressed air energy storage projects currently in operation include the McIntosh Energy Storage Power Station in Alabama, with a power generation of 110MW; the Norton Energy Storage Power Station in Ohio is under construction with a planned power generation of 2700MW; the Anderson County Energy Storage Power Station in eastern Texas is scheduled to start construction in May 2013, with a planned power generation of 317MW; for other energy storage projects, there are currently about 190MW projects in operation.
The two most active chemical energy storage system suppliers in the United States are A123 (using lithium-ion battery technology) and XtremePower (using advanced lead-acid battery technology). At the end of 2012, the two companies will have more than 120MW of energy storage projects put into operation; by the end of 2012, the total number of projects planned to be put into operation in the United States will reach 160MW.