Integrating Battery Storage with Renewable Energy
Most new utility-scale renewable energy projects, such as installations of solar and wind generation, are now including battery storage.
The growing trend of integrating storage is making such projects more financially attractive, as it enhances the generation profile of the installation. Storage helps smooth the power supply, enabling electricity to flow from a project even when the sun isn’t shining or the wind isn’t blowing. It brings more reliability, more resiliency, and many of these systems can be used for voltage correction, and frequency response in the grid.
An Oct. 1 session of Experience POWER, supported by POWER magazine, titled “Battery Storage Integration with Renewable Energy,” looked at several of the factors that developers need to consider when pairing storage with renewable energy. The panelists—Geethalakshmi D of Tata Consulting Engineers, Chris Evanich of Schneider Electric, and Ian Hutt of Commonwealth Associates—discussed what integrated systems are working well, and outlined where the pairing of battery storage with renewable energy can be most beneficial.
Ramp Rate Control
Geethalakshmi said many battery energy storage systems, or BESS, are used for photovoltaic (PV) ramp rate control. The BESS is designed to reduce the ramp rate of solar PV, thereby “smoothing the output power to the grid,” helping meeting grid code requirements. She talked about the algorithm for PV ramp rate control, which includes a need to “compute the battery power capacity considering the design requirements.”
Evanich discussed many aspects of control systems for pairing batteries with renewables, offering three recommendations.
“Looking at a holistic view,” Evanich said, saying developers should start with a holistic design that covers the grid edge. “This is important because battery energy storage started off with being really centrally located, and it was only installed at substations. And now what we’re seeing is a lot of energy storage systems being installed behind the meter.”
Evanich said studying battery storage through multiple use cases, and utilizing intelligent economic optimization software also are keys. “You’re able to reduce energy costs and provide resilience,” he said.
“We’re seeing batteries going all over for different reasons,” said Hutt. “The cost has really come down in recent years and is expected to fall pretty heavily as manufacturers ramped up, and the learning curve for batteries has really gotten better.”
Hutt said the true value of BESS installations is being overlooked. He discussed capital deferment, which he said is where energy storage can enable utilities to put off infrastructure upgrades, as they use storage to increase their energy supply.