The growth of fluctuating renewable energy sources requires flexible, low-cost and efficient electrical storage to create balance between supply and demand as well as security of supply.

By integrating Carnot Batteries in their existing infrastructure, combined heat and power (CHP) plants and coal-fired power plants are able to reduce or eliminate the use of fossil fuels from their production. A Carnot Battery helps balance the electricity grid, while energy utilization is optimized significantly. Moreover, security of supply during peak load periods is created and integration across energy sectors is strengthened.

How does it work?

A Carnot Battery transforms electricity into thermal energy. During the charging process, excess electricity from PV panels and wind turbines is converted into heat by means of a heat pump and stored in molten salt tanks. During the discharging process, the stored heat is converted back into electricity. The waste heat from this process can subsequently be used for district heating.

Technology benefits

✓    Utilization of excess wind- and solar power
✓     Cost-efficient energy storage
✓     Security of supply
✓     Balance between supply and demand
✓     Increased flexibility
✓     Supports electrification

Coal retrofit

Coal power plants destined for phase-out could see new life serving the green economy as thermal Carnot Batteries. The fossil fuel boiler is replaced by two molten salt tanks. The salt reaches temperatures of up to 565°C and is used to generate steam for operating a turbine to produce electricity. A large part of the existing infrastructure can be reused, including the steam turbine, generators, condensing heat exchangers and high value components for switching, transforming and transmitting high voltage power.

Combined heat and power production

Combined heat and power (CHP) plants can be converted into green power plants by replacing fossil fuels with a Carnot Battery. By integrating molten salt tanks, CHP plants relying on gas, coal or biomass can reduce or completely eliminate fossil fuels from their production. Depending on individual energy requirements, a Carnot Battery can act as a supplement to an existing energy source or as a stand-alone unit for complete fossil fuel displacement.

The molten salt tanks act as thermal energy storage. The CHP plant purchases electricity from the grid when the price is low and supply exceeds demand. A heat pump converts this excess electricity into heat, which heats the molten salt. When demand exceeds supply, the stored heat is converted back into electricity and fed to the grid. The waste heat from this process is used for district heating.