Pioneering Storage System Debuts in FL

The new system’s capability increases the amount of solar energy delivered to the grid by more than a half-million kilowatt-hours annually.

DeSoto County Commission Chairman Jim Selph (left), Florida Power & Light Company (FPL) President and CEO Eric Silagy and DeSoto County Commissioner Terry Hill discuss the company's new battery storage technology at the FPL Citrus Solar Energy Center in DeSoto County, Fla., Feb. 9, 2018. During the commissioning of the company's third and newest solar power plant in DeSoto County - FPL Wildflower Solar Energy Center - the company unveiled what is believed to be the country's first-of-its-kind solar-plus-battery storage system that increases the amount of energy a solar plant delivers to the grid. Photo credit: Alex Menendez for FPL. (PRNewsfoto/Florida Power & Light Company)
From left, DeSoto County Commission Chairman Jim Selph, Florida Power & Light Co. President and CEO Eric Silagy and DeSoto County Commissioner Terry Hill discuss the company’s new battery storage technology at the FPL Citrus Solar Energy Center in DeSoto County, Fla. Photo credit: Alex Menendez for FPL.

In a first for the U.S., the Florida Power & Light Co. FPL  is launching a large-scale application of DC-coupled batteries at a solar power plant in the U.S. The new system, providing 4,000-kilowatt/16,000-kilowatt-hour storage capacity consisting of multiple integrated batteries, will increase the plant’s overall output.

FPL, a subsidiary of NextEra Energy, first incorporated this innovative pairing of solar and storage technology into its two-year-old Citrus Solar Energy Center in DeSoto County, an area with more solar panels than residents.

With an average of 246 days of sunshine each year, the state ranks ninth in the strength of the sun’s rays and 12th in installed solar capacity. FPL anticipates that by 2020, solar’s share of the company’s energy mix will outpace coal and oil combined.

The new technology will not increase the peak output of the plant. However, the DC-coupled batteries have the potential to harness extra energy generated by solar plants when the sun’s rays are the strongest. In addition, the system offers the signature capacity of solar-plus-storage installations to the ability to store energy for later delivery,

“By harnessing more solar energy from the same power plant, this has the potential to further reduce our fossil fuel consumption and save our customers even more money on their electric bills,” Eric Silagy, president & CEO of FPL, told environmental and community leaders in DeSoto County in early February.

Saving Millions

 FPL estimates that this potential could add up to millions of kilowatt-hours of solar energy annually. At times a solar plant may generate more power than can be processed by its inverters, the electronic devices that take direct current from the source and change it into alternating current. That leads to lost generation potential. With the new DC-coupled system, that lost potential generation can be captured and stored for later use.

Another benefit of the new technology is that it can improve the predictability of solar energy, which fluctuates with the level of sunshine. That improved reliability FPL to transmit power more efficiently to other power plants, thus saving fuel costs.

FPL is Florida’s largest generator of solar energy, with 10 major facilities and a variety of other solar installations, which total more than 635 megawatts of capacity. Four 75-Mw plants delivered in early March expanded the company’s installed capacity by 300 megawatts.  Moreover, between 2016 and 2023, FPL estimates it will install more than 10 million solar panels, further cutting carbon emissions which are about 30 percent cleaner than the U.S. industry average.

The power provider commissioned its first universal solar installation in 1984—a 10-kilowatt photovoltaic facility in Miami. Three decades later, the utility company became the first to build solar cost-effectively in the state, with the construction of three, 74.5-megawatt universal solar energy centers, each capable of generating sufficient solar energy to power about 15,000 homes.