Battery Balance of System Charrette for Residential and Business Storage of Solar Energy
November 12, 2014 • San Francisco, CA
Rocky Mountain Institute, one of the country’s leading pioneers of renewable energy research and strategy, is engaged in a major effort to accelerate the transition to renewable energy sources by dramatically lowering the cost of battery storage in American homes and businesses.
In 2010, with the hardware costs of solar photovoltaic (PV) modules plummeting, RMI discovered that associated costs that covered permitting, installation, and inspection remained stubbornly high. To accelerate the PV market share required reduction in such costs. RMI convened a ‘Solar Balance of System Charrette’ that catalyzed a partnership with the Department of Energy to focus industry attention on those costs. That led to a multi-year PV program that has guided federal R&D spending, steered business investment toward new hardware, and spawned innovation to reduce costs.
Now, RMI is focussing on the batteries that will allow homes and businesses to store electricity on-site for use when the sun is not shining. This will address one of the greatest obstacles to widespread adoption of solar energy. The cost of lithium-ion batteries, the most popular battery for distributed storage systems, is expected to decline dramatically in coming years due to the growth of the electric vehicle market and utility storage mandates. But the associated balance of system costs — battery enclosure, installation costs, power electronics, controls, permitting and inspection costs — are still high. One estimate is that the balance of system costs are currently responsible for 50-80 percent of the total cost of distributed energy storage systems.
RMI research has shown that, with current market trends, combined battery and solar systems can be cost effective for most of the country by 2040.
RMI will bring together leaders from battery manufacturers, solar companies, the Department of Energy, and utilities to develop ways to reduce the cost of battery systems for storage of solar energy.
Blackstone Ranch Institute has offered an initial challenge grant to attract other funders and support the future development of this initiative.