Batteries, Energy Storage, Solar

FPL Unveils Solar-Plus-Storage That Increases the Plant’s Output

By Editors of Power Engineering

Florida Power & Light Company today unveiled a new solar-plus-storage system that is believed to be the first in the country to fully integrate battery technology with a major solar power plant in a way that increases the plant’s overall energy output.

By incorporating this new technology into the 74.5-MW FPL Citrus Solar Energy Center, FPL expects to increase the amount of solar energy that the plant can deliver to the electric grid by more than half a million kilowatt-hours a year.

“Every day, we work on new ways to better serve our customers with technology innovations and efficiency improvements. That’s how we continue to set the standard for advancing clean energy affordably – including building solar power plants at a lower cost than anybody. Now, with advances in battery storage technologies, we are looking at the next level,” said Eric Silagy, president and CEO of FPL. “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.”

The new system features a 4,000-KW/16,000-KWh storage capacity comprised of multiple batteries integrated into the operations of the FPL Citrus Solar Energy Center.

The new solar-plus-storage system unveiled today is the first large-scale application of DC-coupled batteries at a solar power plant in the U.S. It has the same advantages of other universal solar-plus-storage installations, such as the ability to store energy and dispatch it to the grid at a later time. A unique advantage of DC-coupled batteries is the ability to harness extra energy that a solar plant generates when the sun’s rays are the strongest.

During these optimal operating periods, a solar plant may generate more power than its inverters can process, resulting in some energy inevitably being lost – or “clipped” by the inverter. Unlike other batteries, a DC-coupled system can capture this extra clipped energy, thereby increasing the amount of energy the plant delivers to the grid.

For several years, FPL and other NextEra Energy companies have been researching and testing battery-storage technologies to study a variety of potential benefits ranging from grid stabilization to improved solar integration. Currently, NextEra Energy companies operate approximately 130 megawatts of batteries with more than 100 megawatt-hours of storage capacity.

In 2016, FPL commissioned several battery-storage pilot projects to test different applications under real-world operating conditions. Systems are currently being tested at Everglades National Park’s Flamingo Visitor Center, the Crandon Tennis Center on the island of Key Biscayne as well as other locations across south Florida. Learnings from these pilots are being applied to FPL’s future plans.

Under the rate agreement supported by the state’s consumer advocate and approved unanimously by the Florida Public Service Commission in 2016, FPL plans to develop 50 megawatts of battery storage over the next few years.

FPL is in the midst of a major solar expansion with more than 520 MW added in the last two years and nearly 300 MW more scheduled to enter service by March 1. From 2016 to 2023, FPL expects to install a total of more than 10 million solar panels.