Are small modular nuclear reactors a viable zero-emission power alternative?

Are small modular nuclear reactors a viable zero-emission power alternative?

In February 2022, KGHM (Poland) and NuScale (USA) signed a contract to place a small modular reactor (SMR) at a KGHM copper-silver mine in 2029.1, 2 NuScale is one of a number of next generation nuclear reactors that utilise inherently safe design philosophies aimed to avoid hazards that eventuated in the Three Mile Island, Chernobyl, and Fukushima Daiichi accidents. NuScale is a miniature modularised water cooled nuclear reactor design.

The wider range of new designs includes thorium molten-salt reactors, high-temperature gas-cooled reactors, and a sodium cooled reactor, among other designs like NuScale which are small versions of older water-cooled reactor designs from the last century.

NuScale targets an LCOE (levelised cost of electricity) of USD$65/MWhe (USD 6.5 cents/kWhe).3 The LCOE cited at the Chilean copper mine sites mentioned above is USD$40/MWhe (USD 4 cents/kWhe, Behar paper4), and of course that is variable renewable energy which disappears at night. Marsden’s analysis at USD$5/ tonne carbon price and rail stored energy favours solar at around USD 6.5 cents/kWhe.5

For Australia, the CSIRO GenCost 2021-22 report makes some LCOE estimates for current technologies and future technologies including SMR.6 The latest largescale solar PV and wind are around AUD$50/MWhe (USD$35/MWhe = USD3.5cents/ kWhe) for direct comparison to the Behar et al. Chilean copper paper cited above. Chilean labour costs are about 25 percent of Australian labour, so this probably reflects the falling cost of solar from Chinese production and improvements in solar technology. CSIRO estimates solar LCOE will fall a further 50 percent by 2040 due to solar PV technology improvements. Also, CSIRO estimates the LCOE from SMR in 2030 which is in the range of AUD$150 to $300/MWhe (USD$105 to $210/MWHe or USD15 to 21cents/kWhe), considerably higher than NuScale’s figures.7 It is unclear what is the basis for this difference. Possibly the NuScale figure is for the hardware only, not the overall operational costs and regulatory burdens for near term nuclear energy in Australia.

Australia, Italy, Germany and Japan have adopted policies and legislation that preclude investment in new civilian nuclear energy projects. If new technologies are developed with better safety profiles, will these stances be re-evaluated? A number of global mining houses like BHP produce both copper and uranium, and nuclear energy is favoured within the mining industry. Declining costs of renewables, declining costs of energy storage, social licence to operate, environmental politics, and the urgency of climate action make this a highly unpredictable topic.