Concentrated solar power

Thermal energy storage is key to the success of concentrated solar power (CSP), but current energy storage in molten salts limits the economic viability of CSP plants in competition with decreasing PV costs.

Concentrated solar power (CSP) has the advantage over wind and PV that it allows for cost-efficient and highly efficient energy storage as part of the plant, enabling on-demand dispatch of electricity or heat or even 24/7 base-load operation. EnergyNest offers a Thermal Battery that is perfectly tailored for parabolic trough plants and direct steam tower- and linear Fresnel plants. The Thermal Battery comes at a much lower CAPEX and OPEX compared with molten salt systems. This is largely due to low-cost materials, as well as its simplicity. The EnergyNest Thermal Battery provides a non-corrosive environment and eliminates the need for dedicated pumps, heat exchangers and electrical heat tracing, and importantly it eliminates the need for specialized operation & maintenance personnel, reducing lifetime OPEX to a minimum.

Revenue opportunities

  • New CSP plant developers can substantially reduce their energy storage costs and submit competitive bids in tenders where parabolic trough or direct steam tower is an attractive option
  • Existing CSP plant owners can retrofit their plants in order to reduce energy losses and sell more electricity during peak hours

Case example

EnergyNest is evaluating a project for a full-scale retrofit Thermal Battery integrated in a parabolic trough plant in the Middle East with highly attractive economics. The installed system offers a cheaper and safer storage system than molten salt, at a much lower cost. The Thermal Battery can be used for morning start-up of turbine and also prolonged generation during sunset, boosting electricity generation by almost 10%. The Thermal Battery system requires no heat tracing and no oil-to-salt heat exchanger, has near-zero parasitic loads, and requires no extra crew for operation. Thanks to its implementation and demonstration at full scale, the EnergyNest Thermal Battery has the potential to significantly improve the plant owner’s competitiveness in future project bids.


  • Project payback of less than 3 years
  • Increases total plant electric output by up to 10%
  • Reduces morning start-up time
  • Reduces night-time parasitic losses
  • Produces night-time gland steam for turbine, all without affecting day-to-day operations

Thomas Palkovich

VP Project Development

+47 9820 8384