Using existing infrastructure to transform urban district heating systems to renewable energy supply
Abstract
In this case study the integration of a river water heat pump at an existing combined heat and power plant was examined with the aim to achieve a 50 % renewable cover ratio in the district heating system of an urban district. Three different concepts were designed in line with the requirements of the German subsidy program “Wärmenetzsysteme 4.0”. Furthermore, the integration of decentralized solar thermal rooftop systems was analyzed regarding the suitable rooftops in the district and the potential feed-in into the district heating system. A focus of the conducted dynamic 15-year simulation with the software energyPRO is on electricity market price induced heat production. The relevant components include the operation of the heat pump and a storage, but also additional combined heat and power and power-to-heat units. The heat supply concepts are compared in terms of operational characteristics and economic efficiency.