Small reactors don’t add up as a viable energy source

By M.V. Ramana and Sophie Groll

The nuclear industry has been offering so-called Small Modular Reactors (SMRs) as an alternative to large reactors as a possible solution to climate change.

SMRs are defined as nuclear reactors with a power output of less than 300 megawatts of electricity, compared to the typically 1000 to 1,500 megawatts power capacity of larger reactors.

Proponents assert that SMRs would cost less to build and thus be more affordable. 

However, when evaluated on the basis of cost per unit of power capacity, SMRs will actually be more expensive than large reactors. 

This ‘diseconomy of scale’ was demonstrated by the now-terminated proposal to build six NuScale Power SMRs (77 megawatts each) in Idaho in the United States. 

The final cost estimate of the project per megawatt was around 250 percent more than the initial per megawatt cost for the 2,200 megawatts Vogtle nuclear power plant being built in Georgia, US. 

Previous small reactors built in various parts of America also shut down because they were uneconomical.

The high cost of constructing SMRs on a per megawatt basis translates into high electricity production costs. 

According to the 2023 GenCost report from the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Australian Energy Market Operator, the estimated cost of generating each megawatt-hour of electricity from an SMR is around AUD$400 to AUD$600. 

In comparison, the cost of each megawatt-hour of electricity from wind and solar photovoltaic plants is around AUD$100, even after accounting for the cost involved in balancing the variability of output from solar and wind plants.

Building SMRs has also been subject to delays. Russia’s KLT-40 took 13 years from when construction started to when it started generating electricity, instead of the expected three years.

Small reactors also raise all of the usual concerns associated with nuclear power, including the risk of severe accidents, the linkage to nuclear weapons proliferation, and the production of radioactive waste that has no demonstrated solution because of technical and social challenges

One 2022 study calculated that various radioactive waste streams from SMRs would be larger than the corresponding waste streams from existing light water reactors.

Reactor containment buildings at pacific gas and electrics diablo canyon power plant getty
Reactor containment buildings at Pacific Gas and Electric’s Diablo Canyon Power Plant, the only operating nuclear powered plant in California. (Brian van der Brug / Los Angeles Times via Getty Images)

The bottom line is that new reactor designs, such as SMRs, will not rescue nuclear power from its multiple problems. Any energy technology that is beset with such environmental problems and risks cannot be termed sustainable.

Nuclear energy itself has been declining in importance as a source of power: the fraction of the world’s electricity supplied by nuclear reactors has declined from a maximum of 17.5 percent in 1996 down to 9.2 percent in 2022. All indications suggest that the trend will continue if not accelerate.

The decline in the global share of nuclear power is driven by poor economics: generating power with nuclear reactors is costly compared to other low-carbon, renewable sources of energy and the difference between these costs is widening. 

Nuclear reactors built during the last decade have all demonstrated a pattern of cost and time overruns in their construction.

The Vogtle nuclear power plant being built in Georgia, involving two reactors designed to generate around 1,100 megawatts of electricity each, is currently estimated to cost nearly USD$35 billion

In 2011, when the utility company building the reactor sought permission from the American Nuclear Regulatory Commission, it projected a total cost of USD$14 billion, and ‘in-service dates of 2016 and 2017’ for the two units. 

In France, the 1,630-megawatt European Pressurised Reactor being built in Flamanville was originally estimated to cost 3 billion euros and projected to start in 2012, but the cost has soared to an estimated 13.2 billion euros and is yet to start operating as of March 2024.

These cost increases and delays confirm the historical pattern identified in a study published in 2014: of the 180 nuclear power projects around the world it studied, 175 had exceeded their initial budgets, by an average of 117 percent, and took 64 percent longer than initially projected. 

The first nuclear power reactor to provide electricity to the US grid, SM1. It delivered a net 1,750 kilowatts of electrical power and operated from April 1957 to March 1973. Decommissioning is underway and it was reported last month it would be completed in August 2026. (Image USACE)

However, the recent projects are even more extreme in the magnitude of the disconnect between expectations and reality.

These reactor projects, and the Hinkley Point C project under construction in the United Kingdom, also confirm another historical pattern: costs of nuclear power plants go up with time, not down. This is unlike other energy technologies, such as solar and wind energy, where costs have declined rapidly with experience.

The climate crisis is urgent. The world has neither the financial resources nor the luxury of time to expand nuclear power. As physicist and energy analyst Amory Lovins argued: “… to protect the climate, we must save the most carbon at the least cost and in the least time.”  

Expanding nuclear energy only makes the climate problem worse. 

The money invested in nuclear energy would save far more carbon dioxide if it were instead invested in renewables. 

And the reduction in emissions from investing in renewables would be far quicker.

M.V. Ramana is the Simons Chair in Disarmament, Global and Human Security and Professor at the School of Public Policy and Global Affairs, at the University of British Columbia in Vancouver, Canada. He is the author of The Power of Promise: Examining Nuclear Energy in India (Penguin Books, 2012) and Nuclear is not the Solution: The Folly of Atomic Power in the Age of Climate Change (forthcoming from Verso Books).

Sophie Groll is a master’s student at the School of Public Policy and Global Affairs, at the University of British Columbia in Vancouver, Canada studying public policy and global affairs. Her focus is on environmental policy, low-carbon energy sources, and net-zero transition discourses.

Originally published under Creative Commons by 360info™.

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