Impact of European market frameworks on integration of photovoltaics in virtual power plants

The sustained development of renewable electric power sources demands new solutions for the integration of small-scale, distributed and volatile generation with limited predictability into the European energy markets and power grid. The aggregation of multiple distributed energy resources with adjustable loads and energy storage systems on a conceptual level as virtual power plants and on a geographical level in micro-grids has received widespread attention as a means to increasing the predictability and reliability of renewable sources and facilitating their participation in energy markets and auxiliary services such as frequency control reserve. In this work, the various rules and regulations for energy and reserve power markets in France, Italy and Germany are reviewed and studied for their impact on the market participation of a small-scale virtual power plant featuring photovoltaic sources and battery storage systems by using a mixed-integer linear programming model for dispatch optimization. Results show that existing minimal amount constraints have a particularly limiting effect on the integration of distributed sources into reserve markets and that reducing reserve contract duration can enhance the ability of VPPs to participate in reserve provision.