On Thursday, Florida Power and Light (FPL) announced that it would retire two natural gas plants and replace them with what is likely to become the world's largest solar-powered battery bank when it's completed in 2021
FPL, a subsidiary of NextEra Energy, serves approximately 10 million customers in Florida. The utility says its plan, including additional efficiency upgrades and smaller battery installations throughout its service area, will save customers more than $ 100 million in aggregate through avoided fuel costs. FPL says its battery and upgrade plan will help avoid 1 million tons of carbon dioxide emissions.
The plan calls for the construction of a 409 megawatt (MW) / 900 megawatt-hour battery installation at the FPL Manatee Energy Storage Center. For context, the largest battery installation in the world was built by Tesla at a Hornsdale wind farm in South Australia; 100 MW / 129 MWh.
The batteries will be charged by an existing solar plant in Manatee County, FPL said. Being able to store solar power in batteries is a huge advantage to the utility. Solar photovoltaic panels are intermittent sources of energy because they only produce power when the sun is shining. Generally, in the morning and in the middle of the day, when power demand tends to low.
FPL did not state which company would lithium-ion batteries or use another chemistry. Lithium-ion batteries are currently the favorite of grid-scale chemical battery systems, however. This week, Bloomberg New Energy Finance wrote that the cost of lithium-ion batteries has dropped by 35 percent since the first half of 2018.
FPL wants to retire were built in the 1970s and have reached the end of their useful life. According to NextEra's 2016 Annual Report (PDF), FPL generated 70 percent of its electricity from natural gas and four percent from coal. PFL has been on a course to change that over the past two years, however. The company says it has spent two decades on a modernization program to replace its legacy oil-burning plants with more efficient natural gas plants. Now, the natural gas is becoming a worst-offender in US carbon emission sources.
"FPL thus remains poised to eliminate its only remaining coal plant in Florida by the end of this year," the utility's press release said. "The company will shut down two coal plants in Jacksonville in 2016 and 2018, respectively, collectively enjoying nearly 7 million tons of carbon dioxide emissions."