Expansion of photovoltaics in Stockholm : Consequences on local power balance and on Fortum Värmes production planning

Abstract: The focus of this study is to determine what consequences a hypothetical large photovoltaic system in Stockholm could have on how Fortum Värme plans the production of heating, cooling and electricity. A literature study about the technical possibilities to combine the production from photovoltaics with the production in a district heating system is done. By analysing the potential for photovoltaics in Stockholm, calculating the possible production of electricity from a larger photovoltaic system and comparing it to the load in the electrical grid, the possibilities to use Fortum Värmes production of electricity as balancing power to the photovoltaic system are determined. An electricity market model is used to create price profiles of the price ofelectricity, which changes with larger amounts of electricity from photovoltaics in the energy system, during certain periods of time. A linear optimisation model is created to optimise the production costs of a simplified system containing Fortum Värmes production units. The production costs are optimised using the price profiles from the electricity market model, in order to understand if and how the planning of Fortum Värmes production of heating, cooling and electricity changes when large amounts of photovoltaics are introduced in the energy system.