A new era of nuclear power beckons, and its from reactors that have already been operating for decades. The best future means getting the most from the past.
With at least 80 SMR designs on the drawing board as well as advanced reactors, novel fuels and coolants, and even fusion, today’s nuclear industry offers a wealth of exciting engineering pointing long into the future. Given these riches it’s perhaps hard for casual observers to turn back to the light water reactors that are the lifeblood of the current nuclear energy industry. That, of course, would be a mistake. Reactors built decades ago not only represent a vibrant field of innovative engineering, but also a long-term future for the nuclear industry too.
A case in point comes from the US, where in February utility group Xcel Energy proposed a new clean energy plan that includes life extensions for both its Prairie Island and Monticello nuclear power plants in Minnesota. The plans will see the two Prairie Island units’ life extended by 20 years, to 2053 and 2054, and Monticello by 10 years, to 2050. Monticello is a 671 MWe BWR that began operations in 1971 while Prairie Island features two PWRs with a combined capacity of 1076 MWe and began operating in 1973.
More recently another US utility company, Constellation, applied for Nuclear Regulatory Commission (NRC) approval to extend the life of its Clinton Clean Energy Centre in Illinois. This 1,062 MWe single unit BWR plant began commercial operations in 1987. Currently licensed to operate until 2027, the plant as built had a nominal design life of 40 years. Now though, Constellation aims to extend that for at least another 20 years, bringing its life almost through to 2050. This development is significant, not least because Constellation – formerly Exelon Generation – owns a further 20 nuclear reactors across the US.
As Constellation President & CEO Joe Dominguez noted, the US desperately needs more clean and firm megawatts to power its homes and businesses: “Sustained investment in our nation’s nuclear power plants, which provide about half of all the clean energy on the grid and are the most reliable source of energy, is essential,” he said.
Evidently these decisions affirm a growing trend to extend the life of these large assets to maximise their economic value and lifetime contribution to clean energy.
This trend of life extension proposals across the nuclear fleet goes beyond the US too. Late last year French power group Engie and the Belgian federal government signed an agreement on life extension for both unit 4 at Doel and unit 3 at Tihange. These units are both PWRs with a capacity of around 1 GW each. The life extensions will add 10 years of operating life from 2026.
At around the same time, MVM Paksi Atomero¨mu Zrt, the operator of Hungary’s Paks nuclear power plant notified the European Union (EU) of it plans to extend the operating lifetime of the four units to 70 years with a 20-year extension. Paks features four VVER-440 units that began operations between 1982 and 1987.
Both these decisions followed on from an announcement by Romanian nuclear utility Societatea Nationala Nuclearelectrica (SNN) that it had signed a deal to extend the life of unit 1 at the Cernavoda nuclear power plant. Cernavoda 1 is a Candu 6 PWR with a capacity of 700 MWe commissioned in 1996.
What’s striking about these recent announcements is they clearly demonstrate there are multiple opportunities for life extension across all the main groups of reactor design. Indeed, some of these reactors have already benefited from a life extension programme and are now on their second. There’s decades of life in these assets, and they therefore represent TWhs of continued clean energy production, as well as long-term economic opportunities and exciting engineering too. Given the safety case is found, it would be criminal not to get the most out of them.
By David Appleyard, Editor, Nuclear Engineering International
