District heating systems and energy conservation—part I

Abstract

The potential for energy conservation in space and water heating for five district-heated buildings of three types in south-west Sweden is analyzed. The energy savings for different conservation measures are estimated using a computer program which calculates daily building energy balances. The annual value of energy savings is estimated as the product of energy savings and the resulting avoided costs for district-heat production summed over all periods with different costs. The costs for energy-conservation measures compared with resulting avoided costs for district-heat production with and without energy taxes and capital costs result in different economic energy-conservation potentials. The energy-conservation potential lies between 30 and 60% of final energy use when both avoided marginal operating costs and avoided future investments in district-heat production are considered together with coordination of long-term planned building maintenance with energy-conservation measures. Avoided future investments are evaluated from the effects on the total district-heat demand resulting from energy conservation and connection of additional buildings to the system.