Clean Energy Technology
Clean Energy: HI-THERM
The HI-THERM Hybrid Concentrated Solar Plant (HCSP) is an innovative solar power plant that combines Concentrated Solar Power (CSP), Solar Photovoltaic (SPV) modules, and Holtec Green Boiler (HGB) long duration thermal storage to provide 24/7 electrical power. During daylight hours thermal energy is collected and stored in the HGB where it can be used to drive continuous turbine operations for around-the-clock power generation or provide thermal energy up to 700°C. This innovative configuration is highly relevant to the European transition to Net Zero, offering an effective means of decarbonising both the grid and industrial heat.
HI-THERM uses heliostats to concentrate sunlight onto a central tower where molten salt is heated and transferred to the HGB for storage and conversion to steam. The Photovoltaic (PV) panels are located where Heliostat’s efficiency is reduced. The system also optimises land use, ideal for deployment on underutilised or brownfield sites across southern Europe.
Clean Energy: Air Cooled Condensers
Holtec’s Air-Cooled Condenser systems (ACCs) feature transformative air-cooling technology that ends reliance on large quantities of cooling water by rejecting waste heat. Featuring space-saving modular components, these proven technologies reduce construction and maintenance costs, and root out operational problems typically present in cyclical, load-following power plants.
Holtec utilises Computational Fluid Dynamics to predict thermal-hydraulic performance, Finite Element Analysis to study fatigue effects and Dynamic Structural Analysis to define the effects of structural loadings on ACCs. These computer models predict the system’s performance under extreme temperature conditions with high reliability.
Holtec has reduced construction time and cost by optimising the modular ACC erection sequence and reducing the number of pieces shipped to a site. A Holtec ACC cell can be assembled on the ground and placed on the support structure in a single lift. Holtec’s ACCs are the first standardised ACCs designed to meet any site requirements without extensive custom engineering.
Clean Energy: Green Boiler
The Holtec Green Boiler is a long-duration thermal energy storage system that provides an efficient, scalable way to store energy from solar, industrial processes, or surplus grid electricity. It functions as both a thermal store and steam generator, producing clean steam at the point of demand. The steam from the Green Boiler can be used to generate electricity or serve as process steam for other industrial applications such as making hydrogen or synthetic aviation fuels.
The HGB is especially relevant to the UK’s growing need for grid flexibility, industrial decarbonisation and low-carbon heating. The standard capacity is 12 hours of discharge at full power which can be increased for particular applications. Unlike batteries the Green Boiler does not have a finite cycle life and is not vulnerable to fire. Green Boiler’s capital cost is competitive with a battery installation with an incomparably longer service life. It can be integrated with renewable energy sources to provide a resilient, non-emitting solution for balancing the grid, supporting the UK’s energy transition. Its use of readily available, non-rare materials also aligns with UK aims to secure sustainable, localised supply chains.
Together, HI-THERM and the Green Boiler represent a holistic clean energy offering low carbon, highly reliable and designed to meet the demands of modern energy systems in the UK and globally.
