This year’s unusually warm summer in the Nordic region has increased sea water temperatures and forced some nuclear reactors to curb power output or shut down altogether, with more expected to follow suit. The summer has been 6-10 degrees Celsius above the seasonal average so far and has depleted the region’s hydropower reservoirs, driving power prices to record highs, boosting energy imports from continental Europe and driving up consumer energy bills. Nuclear plants in Sweden and Finland are the region’s second largest power source after hydropower dams and have a combined capacity of 11.4 gigawatts (GW). Reactors need cold sea water for cooling but when the temperature gets too high it can make the water too warm for safe operations, although the threshold […]