In 2015, Électricité de France put out a pamphlet titled Flexible nuclear generation to foster the development of renewable energy as one of its “50 Solutions for the Climate.” The pamphlet boasts of the flexibility of EDF’s nuclear fleet, showing a 1.3 GW nuclear power plant increasing and decreasing its output by 70% within 30 minutes. The documentation centers on the Golfech plant, and shows these impressive feats of rapid ramping, with two cycles up and down within a 24 hour period. And while EDF noted that such cycling was prompted by daily changes in demand, it also stresses that such capabilities will be able to make nuclear power a good complement to the fluctuating output of wind and solar on the grid. However, in Northern Germany a situation has played out which challenges this line of reasoning. In February the Brokdorf nuclear power plant was taken offline after damage to its fuel rods was found. According to a local nuclear supervisory authority, the operation of the plant in “load-following” mode had contributed to unexpected oxidation of the rods. As of July, the plant was operating in “safe mode,” and politicians from Germany’s Green Party are calling on a Swiss reactor near the German border with similar problems to be shut down. So can nuclear accompany high levels of renewable energy? This is a technical and economic question, and one that has ramifications for the future of the technology. Nuclear power plants are regularly ramped up and down in France, to partially respond to the shift in electricity demand from day to night. Additionally, in other nations plants such as the Brokdorf facility are ramped to respond to fluctuations in wind and solar generation, although the vast majority of nuclear power plants are not. The nuclear industry claims that all currently deployed boiling water reactors (BWR) and pressurized water reactors (PWR), which make up the entire nuclear fleet in the United States and the majority in Europe, can ramp quickly. However, IASS Potsdam Senior Fellow Craig Morris, who has written extensively about nuclear energy and renewables, has stated that “no nuclear fleet worldwide is ramping to any significant extent, so we actually have no idea whether ramping will work in practice.” While developed nations should prioritize rapid decarbonization over short-term costs, there is not now and never will be an unlimited amount of money to pour into this problem. The nuclear industry knows this, and as such the attempt to cast nuclear power plants as a suitable accompaniment to high levels of wind and solar is ultimately a desperate act by an industry which is in severe crisis in both Europe and the United States. Nuclear reactors may be able to ramp (within limitations), but ultimately nuclear is fighting for space on the grid with wind and solar. As such the building of new nuclear power plants, and in some cases the extension of licenses for old ones, can limit the transition to renewable energy
PV Magazine 5th Sept 2017 read more »
