Solar power in northern Scandinavia, its impact on the grid and methods to mitigate this impact

This paper presents results from measurements of solar-power production in the north of Scandinavia; studies of the impact on the grid when larger amounts of solar power are installed, and methods to mitigate this grid impact. It is shown that solar power has limited contribution to reducing the peak loading of the grid. Large amounts of solar power will even increase the peak loading. Curtailment is shown to be an appropriate way of allowing more solar energy to be injected into the grid without additional grid investment. It is important however to use the right control method (“soft curtailment”) as otherwise production will decrease with increasing installed capacity. It is also shown in the paper that unacceptable voltage variations can occur when large installations are connected to weak parts of the grid. The availability of hourly metering data is an important contribution to integration studies.