Annex 25

Surplus Heat Management using Advanced TES for CO2 mitigation

The world’s total energy supply is 136500 TWh/year whereas the energy use is approximately 94000 TWh/year (IEA Key Statistics, 2008). By inspecting these figures, one can see that close to 1/3 of the world’s energy supply is “wasted” in energy conversion. In reality, the number is even larger, perhaps as much as 50%, since for example the tank-to-wheel efficiency of engine driven transportation is only 20%, and boiler efficiencies seldom are above 90%. From a sustainability perspective, increasing the efficiency in many energy conversion processes is crucial. As the demand for energy increases in all sectors, and all over the world, waste heat management will be a cost-effective way of securing the supply of energy and power while mitigating the emissions of CO2. Such management is most effectively done in cases where the waste heat flow are large, like industrial processes, or in cases where the value of increases waste heat utilization is large, like in the vehicles and transporting goods sector. Recent advances in compact thermal energy storage has encouraged this initiative to explore solutions where waste heat management can be enhanced, facilitated and even enabled by integrating thermal energy storage technology. The general objective of this Annex is to identify and demonstrate cost-effective strategies for waste heat management using advanced TES.