Thermal Buffer Technology

2026-11-03

The following summary is not intended as a complete or definitive specification of the requirement. A purpose of this engagement is to seek information from the market to help refine our understanding and aid the development of a future specification. UKIFS is seeking experts to support the design and development of a thermal storage system that integrates with the STEP power cycle. While the power cycle is designed to efficiently integrate heat from the tokamak device during a high power steady state scenario, the power cycle and cooling systems must also be highly flexible to adapt to uncertain prototypic operations e.g. the systems must have the ability to switch on and off and ramp up and down at the start and end of operational periods. Significant thermal power will be generated from the tokamak device during the ‘rapid density rise phase’ of the reactor plasma ramp up, lasting a few minutes. This is an effective ramp of 2GWth generated from the tokamak during these few minutes. To manage this very immediate and sudden generation of heat from the tokamak, a minimum amount of thermal storage will be needed to increase the thermal inertia of the primary coolant loops, allowing the power cycle to ramp up to 100% load in a timely manner. Further, thermal storage may be needed to enable partial operation of the power cycle during the transition between the initial pre-heat to part load operational period. The thermal storage system will be expected to extract heat from a hot CO2 primary coolant during the ramp up phase and deliver heat back to the CO2 primary coolant (or to a separate secondary working fluid) during the ramp down phase. The proposed technical operating conditions of the thermal storage system and load requirements are: -CO2 primary coolant operating pressure: 50 to 150 bar. -CO2 primary coolant operating temperature: 550°C to 650°C. -Thermal duty in the region of 800MW. -Required energy storage of 150MWh. -Required fast ramping duration in a few minutes. Systems of interest & key words: -Thermal energy storage -Latent heat storage -Sensible heat storage -Thermochemical heat storage -Thermal battery -Molten salt storage systems -Molten salt heat exchangers/ steam generators -Phase change materials -Metallic phase change materials -Solid state energy storage -Packed bed storage -Concrete battery -Sand battery Please note that the CPV codes given in this notice have now been corrected. To view this notice, please click here: https://ukifs.delta-esourcing.com/delta/viewNotice.html?noticeId=1009995808

United Kingdom (UK)

2026-04-02