Bachelor's thesis Stefan Eckl
Economic comparison of electrical and established heating systems with regard to the decreasing heating load through improved building insulation
To meet the energy policy objectives of the German federal government energy saving regulations (EnEV) were introduced. With the target of heat transfer coefficients these regulations specify the degree to which the heat demand of buildings must be improved. Nowadays the low-energy houses are heated primarily with fuel-powered boiler or electric heat pumps, which are characterized by high investment costs and low operating costs. Based on the ongoing improvements of the building insulation standards, investment costs get a greater importance by the decreased heat energy demand. Thus, the examination of direct electric heating systems gets economically interesting due to lower investment costs compared to the established heating systems.
The aim of this thesis is to create an application that allows a rapid assessment of the conditions under which the various heating systems are economically attractive. To this regard evaluating the combination with a photovoltaic system, the advantages of accurate dynamic simulation are combined with the advantages of rapid annual balance sheet. Based on this the dynamic heating loads are determined from a building simulation with the adjusted insulation standards. The auxiliary energy and heat losses of the heating systems, which are not provided in the building model are accounted for over the year. Furthermore, to calculate the total annual cost, the investment costs of heating systems and the information used to calculate the operating costs are collated with a literature review. From the dynamic simulation and the static annual accounts, the total annual costs are calculated. Thereby the boundary conditions get varied to record the influences on cost efficiency. For calculating and visualization of the results those application is used which enables a rapid change in the boundary conditions.
Based on the current energy prices the direct electric heating systems are economically viable only for buildings with very low specific heating energy demands. Due to the current low fuel oil and gas prices, the operating costs of the established heating systems compensate for the higher investment costs.With an increase in fuel prices or reduction of the investment costs of electric heating systems, those become an economical alternative to the established heating systems for the nowadays usual low-energy houses. In particular favors a combination of heating systems with a photovoltaic system the operating efficiency of the electricity system to a greater extent than the established heating systems.