By Editors of Power Engineering
A new study by the National Renewable Energy Laboratory indicated current solar facilities with on-site battery storage are not yet as economical as solar facilities without on-site storage.
The study, which examined solar systems in Southern California, indicated the cost of the batteries along with 2014 solar electricity prices caused the cost-benefit ratio to fall well short of standalone solar arrays.
Though AC-coupled and DC-coupled systems increased the cost-benefit ratio slightly, even 30 percent investment tax credits only pushed the ratio to just below 1.4. Photovoltaic solar alone had a cost-benefit ratio of slightly above 1.4.
As the energy storage market continues to mature, battery costs should fall. However, the study indicated energy storage would provide a much better cost to benefit ratio in areas with higher photovoltaic penetrations than solar alone by 2020. Solar plus storage would show a cost-benefit ratio mostly similar to solar alone, not including investment tax credits.