We make this waste heat usable by raising it to a higher temperature. This can be done, for example, with heat pumps in which the refrigerant absorbs energy on one side (the evaporator side), is compressed by an electric compressor and re-emitted at a higher temperature on the other side (the condenser side).
This not only saves energy but also CO2. After all, the waste heat valorised in this way no longer needs to be generated by a fossil boiler, and the electricity needed for the heat pump can be produced by renewable energy sources or qualitative cogeneration.
To correctly determine the potential for waste heat valorisation, both the available waste heat and its users must be mapped via a Pinch analysis. In addition, simultaneity must also be considered. When energy flows are not synchronous, thermal storage can offer a solution.