The design of Holtec’s HI-HEAT district heating system, which has been under development since May 2020, has been deemed complete and digitally verified.

This low-pressure steam supply version of Holtec’s Green Boiler is engineered to deliver a carbon-free district heating solution that reduces dependence on fossil fuels. The technology harnesses an external heat source such as surplus electrical energy available during off-peak hours, a co-located nuclear reactor or theSchematic of the HI-HEAT district heating system. Source: HoltecSchematic of the HI-HEAT district heating system. Source: Holtec molten salt from a nearby solar power plant. The external thermal source heats the Feorite thermal capacitor to elevated temperatures reaching 700° C. A single shop-manufactured HI-HEAT module stores over 300 million BTUs of thermal energy in the capacitor, sufficient to produce 300,000 pounds of steam.

[See also: New tech to supplant gas-based district heating]

The ability to produce high pressure/high superheat steam in the Green Boiler affords the opportunity to repurpose coal fired plants, which would otherwise be completely dismantled. The high-pressure variant of the Green Boiler can also be used to power the turbogenerators of existing coal fired boilers, which can be retired along with their coal and ash handling facilities.

Holtec is now advancing the integration of Green Boiler technology with solar heliostat/receiver technology to provide a clean source of high pressure/high temperature steam in support of hydrogen fuel production, electric power generation and industrial process steam delivery.

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