Stone Edge Farms microgrid tour draws 100 attendees

The ESS Iron Flow Battery at Stone Edge Farm is a 10 kW/60 kWh long-duration, long-life system that has been performing successfully since early 2016.

ESS Inc., manufacturer of a safe, low-cost and long cycle-life battery for renewable energy storage, celebrated a highly successful presence at Intersolar 2016 in San Francisco this month, boosted by strong interest in the company’s Iron Flow Battery technology, a steady flow of booth visitors, and an overflow of participants for the site tour at Stone Edge Farm in Sonoma.

More than 100 Intersolar attendees took part in a tour of Stone Edge Farm’s advanced microgrid—four times the expected number. The tour’s popularity was a reflection of the growing interest in the benefits of energy storage, especially in support of integrating renewables to provide grid services, lowering electricity costs and reducing CO2 emissions. At Stone Edge, ESS’s Iron Flow Battery is well suited to provide long-duration storage capacity to supply power at night, for irrigation or hydrogen generation, and during the day to smooth out the intermittencies of solar PV.

“Our unique flow battery technology and value proposition clearly resonated with the attendees we met with at the show,” said Craig Evans, CEO of ESS. “Our conference presentation emphasized our low levelized cost of storage, as well as the many benefits associated with an all-iron flow battery, including the uncoupling of power and energy capacity for greater flexibility. It was especially gratifying to see the interest in this technology and how it’s performing as part of an advanced microgrid—which is a real-world demonstration of the value of clean and sustainable long-duration energy storage.”

The ESS Iron Flow Battery (IFB) system installed at Stone Edge Farm was easily sited in an environmentally sensitive area, thanks to its small footprint and non-toxic, non-flammable chemistry. Its core element is earth-abundant iron, dissolved in salt water as the energy storage medium. By combining this low-cost electrolyte with a proprietary battery design, ESS’s IFB technology has demonstrated thousands of deep charge and discharge cycles at 70% AC/AC round-trip efficiency, without performance degradation, resulting in the lowest levelized cost of storage (LCOS).

“Installation and commissioning of the ESS iron flow battery could not have gone more smoothly,” said Craig Wooster, microgrid project manager at Stone Edge Farm. “The fact that the system can be shipped without water saves considerably on freight and handling. We’re looking forward to leveraging its long-duration storage capabilities to provide essential services and contribute to Stone Edge Farm’s carbon-neutral footprint.”