Just over US$28 million has been awarded by the US Department of Energy to projects that could deliver energy storage durations of up to 100 hours, while also committing US$120m to the Joint Center for Energy Storage Research (JCESR).

First developed by NASA, flow batteries are a potential answer to storing solar – and wind – for eight to 10 hours, far beyond what is commonly achieved today with lithium-ion. In the first of a two-part special report, Andy Colthorpe learns what the flow battery industry faces in the fight for commercialisation.

The CEO of Primus Power agrees that at present, lithium battery systems are more bankable than the flow battery energy storage systems of the type his company makes, but asserted that he believes this will change over time.

Primus Power is among a handful of makers currently commercialising their flow batteries, with rivals that include RedT, VIZn Energy and Redflow. Early customers have included Microsoft, which installed a Primus battery at its corporate HQ in a pilot project. Andy Colthorpe spoke with Primus Power CEO Tom Stepien to learn more.

A test and demonstration facility operated by South Africa’s main utility Eskom will trial Primus Power’s flow batteries, after a local developer was awarded a grant for the project by the US Trade and Development Agency (USTDA).

California-headquartered provider of low-cost, long-duration storage systems Primus Power has launched the EnergyPod 2, the second generation of its long-duration, fade-free flow battery.

Financial activity in the third quarter of this year was slightly flatter than Q2 for smart grid, batteries, energy storage and energy efficiency, but the average deal size grew, according to Mercom Capital Group.