200 White-Hot Toaster Ovens To Expand the US Wind Power Profile

A groundbreaking energy storage project is underway in South Dakota, aiming to bolster the US wind power sector by capturing and utilising surplus renewable energy. Commissioned by biofuel producer POET, the facility employs a 5 gigawatt-hour system featuring over 200 solid carbon blocks that function similarly to giant toaster ovens. These blocks store excess wind power generated during periods of low demand, which would otherwise be curtailed, and convert it into either electricity or high-temperature heat for industrial use at POET’s Big Stone City ethanol plant in North Dakota. The technology behind this innovative storage system comes from Antora Energy, a California-based startup that has developed specialised carbon blocks capable of dual discharge modes. Unlike conventional batteries that only release electricity, Antora’s system can also emit intense heat through thermophotovoltaic (TPV) cells, which convert infrared light from superheated carbon into usable energy. This approach not only addresses the intermittency of renewable sources but also provides a flexible, zero-carbon heat and power solution tailored to industrial processes. TPV cells, originally conceived in the 1960s, have historically struggled with efficiency and cost barriers, limiting their commercial adoption. However, Antora has made significant strides by optimising these cells to operate at much higher temperatures—between 1,900 and 2,400 degrees Celsius—achieving conversion efficiencies of around 40%. Supported by funding from the US Department of Energy and partnerships with institutions like MIT, the company has revitalised this technology, positioning it as a viable component of future renewable energy grids. Looking ahead, Antora is scaling up production with a new manufacturing plant in San Jose, California, designed to produce ready-to-install thermal battery modules for industrial customers nationwide. The Big Stone City project, completed in under a year, serves as a proof of concept for rapid deployment of utility-scale energy storage that can directly replace fossil fuel use on site. As the system phases in full operation by October, it exemplifies a promising step towards a decarbonised energy infrastructure capable of maximising wind power utilisation across the United States.