Modeling heat pumps as combined heat and power plants in energy generation planning

The development of power and heat generation from concentrated large power plants and conventional heating systems towards the joint, efficient and partially distributed generation in so called combined heat and power plants is a challenge for the energy industry. Due to the increasing degree of decentralization the ability to consider a variety of assets and different technologies in a power plant portfolio becomes necessary. In this work, the technical characteristics of heat pump heating systems are analyzed and evaluated in terms of degrees of freedom and optimization potentials in the energy generation planning. A model for the optimized scheduling of heat pumps under consideration of all of the technical constraints, such as variation of the efficiency over time, is proposed and implemented in an existing procedure. It is shown that heat pumps are suitable for integration into energy generation planning. Beyond this, a model for generating an hourly thermal demand by using standard load profiles and temperature data is proposed. Based on an existing standard for the dimensioning of combined heat and power units, the possibility to estimate close to reality time series of the load and to use them in the energy generation planning is presented. Investigations lead to the conclusion that groundwater heat pumps are the most efficient technology and that savings of up to 9 %/a in terms of generation costs are possible due to the use of a power control.