In the south of Sweden there is a general shortage of energy to the point where reserve energy operators have to jump in to supply energy. Those are basically t

In the south of Sweden there is a general shortage of energy to the point where reserve energy operators have to jump in to supply energy. Those are basically the most expensive energy production you can have. In addition there is a speculative market so available energy production can be bought at one price point and then sold at a higher, making the speculative provider a even higher "cost of production". If however there is a energy surplus in a region then two things happens. Reserve operators don't need to be used, and the speculative market risk holding energy that they can't sell, thus forcing lower prices.