Grid Scale, Microgrids, Solar, Storage

SunEdison Recruits Imergy Flow Batteries for Microgrid Rural Electrification Initiative

Earlier this year, SunEdison announced a goal to bring power to 20 million people in rural India by 2020. To forward this mission, it announced today that it will use more than 1,000 flow batteries from Imergy Power Systems for its solar-powered minigrid projects.

The solar-powered minigrids are anchored to telecom towers near remote villages with batteries typically ranging from 30 to 120 kWh. The system provides 24/7 power for the tower, while also powering surrounding villages. Instead of purchasing expensive kerosense or simply living in darkness, villagers are able to charge their devices or wire lighting to the village itself. According to Imergy CEO Bill Watkins, about 5,000 villages fit this telecom model.

Imergy is no stranger to off-grid applications. It’s storage technology has already been installed in both India and several parts of Africa. While in the U.S., the Navy is currently testing its applications in a smart microgrid project.

Its technology uses recycled vanadium from environmental waste, which is stored in tanks and circulated during charge and discharge cycles.  Since the chemicals are stored in separate tanks, the system can be scaled up or down fairly easily. And while flow batteries have a shorter response time than other battery technologies, they are ideal for off-grid applications, according to Tim Hennessy, Imergy President and COO. 

“We can scale energy. If you’re looking to store it for 24 hours, you can’t do it with other batteries or costs would become exorbitant,” said Hennessey. “There is no software to manage, a deep charge lasts all day long, and it can withstand harsh environments.”

Back in December 2013, Imergy told REW that its costs were on track to reach $300/kWh by 2015. Hennessey said that they are still on track for that number to become a reality, but emphasized that the industry needs to look at the levelized cost of energy to understand true costs.

“Everyone talks about costs, but the fact is that [vanadium flow batteries] will last 20 years on energy storage cycle, and vanadium itself never wears out. While lithium-ion batteries may be ‘cheaper,’ they have a much shorter lifespan and are less scalable,” said Hennessey. “We are actually cheaper than other technologies over the lifetime of a battery.”

But while everyone is interested in the technology and economics, Watkins and Hennessey want to emphasize the importance of these rural electrification projects.

Hennessey explained what he called the “battle of the last mile.” When industry cannot justify extending transmission an additional five miles, many villages are left in the dark. However, when the villages get off-grid power, businesses start to crop up and demand increases, which then eventually justifies transmission investment. But since India’s transmission system is so unreliable, these villages are now relying on renewable energy systems, which are creating huge economical growth.

“The big picture here is the fact that so many people in this world don’t have electricity. When we enter these villages, it gets very emotional — most of them has never seen electricity in their lives,” Imergy’s CEO Bill Watkins. “Yes, of course we want to make money for investors, but this is a big deal…This is a way to reach these people and have them be a part of the world — we can’t even fathom the impact.”

Lead image: Rural india. Credit: Shutterstock.