Oslo, Norway: EnergyNest has developed a thermal energy storage system to allow a frequently underused resource, industrial waste heat, to be transformed into useful energy. Once stored, the time-shifted waste heat can be used in a variety of ways – to produce process steam, to generate power, or to stabilize entire power grids.
A single EnergyNest Thermal Energy Storage module, fitting into a standard 40-foot container, provides an energy capacity of up to two megawatt hours thermal. Due to its modular structure, the system can be specified to individual requirements and scaled up into the gigawatt hour range. (PRNewsFoto/EnergyNest)
One element of this new technical solution is the HEATCRETE® substance, a high performance concrete composed of 75% quartz aggregates and 25% additives. A steel carrier structure encloses HEATCRETE®-embedded carbon steel pipes, through which a heat transfer fluid charges and discharges the storage system at a pressure of up to 160 bar. (The bar is a unit of pressure, equivalent to .987 atmospheres, or 14.5 pounds per square inch.) A single module, fitting into a standard 40-foot container, provides an energy capacity of up to two megawatt hours thermal. Due to its modular structure, this system can be scaled up into the gigawatt hour range.
At around 20-25 US dollars per kilowatt hour, the company says its system is appreciably cheaper than other energy storage technologies and a fraction of the cost of a battery-based system. Due to its rigid structure and the absence of moving parts, the storage system works virtually maintenance-free, the company says, with operating costs a fifth of what other storage systems require. The potential for power generation via time-shifted waste heat is “tremendous,” the company claims. Companies can for example avoid peak price tariffs with their own waste-heat-to-power installation.