Swedish electricity production stands on three major legs, but the legs have their shortcomings. Johan Lindahl, Swedish representative to the International Energy Agency (IEA), explains why solar power is the perfect complement to balance the Nordic electricity system.
Imagine a beautiful high summer day. The sun is high in the sky, it is warm and not a breath of wind is felt in the air. Wind turbines are at a standstill, but solar electricity production is at full speed.
– “Sweden’s electricity mix is based on four pillars: hydropower, nuclear power, CHP and wind power,” says Johan Lindahl.
– But their production is not constant, and demand varies both during the day and throughout the year. Solar energy complements the other power sources because it produces the most when the others produce the least.
Hydro, wind, cogeneration and nuclear power all produce more electricity in winter than in summer. Hydropower because the demand and inflow is greater then, wind power because there is more wind then, combined heat and power (CHP) because it is dependent on heat demand via district heating, and nuclear power because it is shut down for inspection and maintenance during parts of the summer months.
– This has actually meant that the power system has been more strained in the summer months in recent years, but since solar power has its peak season then, it is a perfect complement to the other four.
The same thing happens on a daily basis. Because we consume less electricity when we are asleep than when we are awake, Sweden consumes on average around 5 gigawatts more electricity during the day than at night.
– Here again, solar power complements the other power sources as it produces the most when consumption is highest during the day. This allows it to balance the high demand in the middle of the day.
At present, solar power accounts for about one percent of Sweden’s electricity production, but expansion is taking place all the time. And more solar power in the system has more benefits than just an electricity market that is better able to handle variations in supply and demand.
– First, it becomes more renewable. We should not forget that our Nordic electricity market still includes coal-fired power plants and that we are interconnected with the rest of Europe where fossil fuels still account for a large share of electricity production. More solar could displace more fossil fuels.
However, the environment is not only about climate change but also includes other aspects.
– Solar power has a smaller footprint in this respect as well. It does not need to dam rivers, it does not harm birds or other animals, it does not generate radioactive waste that is dangerous for a hundred thousand years. And even if you put it on land, it has been shown that if properly managed, a solar park can become a meadow with higher biodiversity than conventional agriculture.
Moreover, more solar electricity in the system could make it more robust.
– A system based on a few large sources of power can be vulnerable, because if one of them fails, the consequences are enormous. However, with several small power sources, which in the long run can also create many small microgrids, the impact of a possible breakdown is much smaller for society.