Li-ion battery boosts solar profit selling peak power to UK grid
Nicholas Beatty, a British farmer and renewable energy investor, says using a £825,000 ($1m) lithium-ion battery to store intermittent energy capacity could increase revenues on his solar farm by up to £200,000 p.a. The Chinese-manufactured battery stores excess energy which is then sold back to the national grid when prices peak to generate a profit. 
The battery and its software give Mr. Beatty an advantage over other solar panel farmers. Power prices in Britain and elsewhere rise and fall, sometimes strikingly, during the day and over the year, depending on the supply and demand. By storing power in the battery, Mr. Beatty can feed it into the grid when prices are high. “The battery effectively takes power off the line when there is too much and puts it on when there is too little,” he said.

Image The battery inside a storage container on Nicholas Beatty’s property can store a substantial portion of the electricity from his solar farm. Credit... Andrew Testa for The New York Times

Mr. Beatty said the battery, which costs about 825,000 pounds, or $1 million, could increase revenue for his solar farm by as much as £200,000 a year. In addition to making more by timing his delivery to the grid, he said he planned to enter an auction to become a standby source of power to compensate for unexpected drops in the grid.

Mr. Beatty is one of many entrepreneurs and businesses trying to play the fast-shifting electric power landscape. The global effort to combat climate change is forcing what had been an old-line business to evolve. Polluting, coal-fired power stations are closing, while clean energy sources like wind and solar are growing fast.

While renewable energy sources have the huge advantage of not emitting the gases blamed for climate change, they can be tricky for a grid operator to rely on, not least because their output is dependent on wind and sunlight. In addition, the power they produce is essentially free, which puts downward pressure on prices. “The growing use of renewables is creating an unstable energy system,” said David Hill, managing director of Open Energi, a British company that helps industrial companies save money by timing and otherwise managing their energy use. “What everyone is trading on now is that there is a value in flexibility.”

Batteries are one way of achieving that flexibility.

Amid all this disruption, Britain and other countries have created a smorgasbord of incentives to power providers to keep the lights from going off. Neil Hutchings, director of power systems and storage at Anesco, the small British company that supplied Mr. Beatty’s battery, said there were no fewer than 14 ways that it could make money. “The real secret is how to pick out the best combination,” he said.