Holtec International has engineered an environmentally sustainable power generation alternative to the use of coal by combining nuclear power and solar energy technologies. The Combined Nuclear/Solar Plant (CNSP) can replace the power block in existing coal-fired facilities to reduce implementation costs while decommissioning of steam production equipment provides the land area needed for solar power systems.

The design is based on Holtec’s SMR-300 small modular reactor, a light water technology-based generator with added gravity-actuated defense-in-depth features for fail-safe emergency recovery capability. Each reactor can produce a minimum of 300 MW (net-electric) power under the most adverse climate conditions and in water-challenged regions, as air can be used instead of water for rejection of the plant’s waste heat. The thermal output per reactor exceeds 1,000 MW.

The CNSP also incorporates a HI-THERM HSP hybrid solar plant, which can deliver as much as 8 MWH of solar heat per acre at equatorial and subtropical sites. This solar energy system is expected to have a service life in excess of 60 years and to meet the 24-hour daily cycle of varying consumer electricity demand.

Base load or on-demand power are provided by the company’s Green Boiler system, a three-in-one device that can store vast amounts of high temperature heat conveyed to it from solar collectors. This component can also supply motive steam at the required pressure and superheat to power the coal plant’s existing turbogenerator. When installed to repurpose coal-fired power plants, the Green Boiler vessels can be sized to operate for 12 hours or longer at full power.