2. Thermal power plant: Thermal power companies may use the waste heat generated by thermal power plants to transport it to users through pipelines.
3. Geothermal resources: Thermal companies may use geothermal resources to convert geothermal energy into heat energy through special equipment and then deliver it to users.
4. Waste incineration power plant: The heating company can use the heat energy generated by waste incineration power plant to deliver it to users through pipelines.