ABSTRACT We are facing climate changes which require immediate action if we are to comply with the agreed global goals of securing carbon neutrality by mid‐century. It has therefore been decided that a greater transition to renewable energy sources worldwide must take place. In this transition, Denmark has chosen to become CO 2 ‐neutral, through, amongst others, 100% usage of renewable energy sources by 2050 and reducing its CO 2 emissions by 70% by 2030. A focus area in this renewable energy transition is the use of district heating (DH). 64% of all households in Denmark are equipped with DH through a well‐established network. Despite being defined as a sustainable heating source, a large portion of the heat is generated from fossil fuels, imported combustible waste, and biofuels. In this study, the opportunities and limitations of utilizing surplus heat for DH are explored and assessed through the exclusive use of secondary data. The accessibility of surplus heat is dependent on temperature quality, availability, capacity, and distance to the DH network. The result of the study indicates that there is a potential for 10% of the total DH heat demand in Denmark can be provided by surplus heat in the near future.
Mickelborg et al. (Sun,) studied this question.