Summary - L.1328 (09/2025) - Specification for waste heat reuse in telecommunication rooms and data centres

In the face of the rapid growth in the size and power density of global telecommunication rooms and data centres, the heat generated by ICT equipment is growing dramatically, but the generated heat is mostly discarded. The waste heat reuse can contribute to reducing the energy consumption of other facilities, which are outside of the boundary of the telecommunication rooms and date centres by heating the facilities. Therefore, the use of waste heat reuse technology facilitates energy saving and carbon reduction in non-ICT sectors.
Recommendation ITU-T L.1328 describes the use cases of waste heat reuse and defines the key metrics of waste heat recovery and reuse. Further, the measurement methodology including the calculation method for the defined key metrics is also described.