Thermo-Chemical District Networks
Abstract
Thermo-chemical networks are a new technology for district networks, which can provide heating, cooling and drying in one heat loss-free multiservice network. The innovation is the use of thermo-chemical fluids as transport medium, e.g. in the form of concentrated salt solutions, rather than water. Due to the hygroscopic characteristics of the salt solutions, a chemical potential is transported and not thermal energy as in conventional networks. The chemical potential is used to generate useful heat or cold from ambient heat at the place and time of demand or to dehumidify air for drying or air conditioning processes. An important advantage of this novel technology is that the technology is heat loss–free, which means the thermochemical potential stored in the fluids degrade neither in the piping infrastructures nor in storages. The aspect of heat loss-free storage is also interesting for applications of seasonal thermal storage. In particular with solar energy, allowing shifting the energy available in summer to the wintertime. Thermo-chemical district networks and the possibility of long-term storages will improve the efficiency and profitability of the use of solar energy in district heating networks.