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Policy and funding

Small modular nuclear reactors are a crucial technology, says report

26 Jan 2018 Hamish Johnston
Schematic of a small modular reactor designed by UK-based Moltex
Small-to-medium: a modular reactor designed by UK-based Moltex

Small modular nuclear reactors (SMRs) offer a way for the UK to reduce carbon dioxide emissions from electricity generation, while allowing the country to meet the expected increase in demand for electricity from electric vehicles and other uses. That is the claim of Policy Exchange – a UK-based centre-right think tank – which has published the report Small Modular Reactors: The next big thing in energy?. Written by the energy-policy specialist Matt Rooney, the report calls on the UK government to support the development of a SMR.

SMRs are usually considered to have electrical outputs of about 300 MW or less. In comparison, the Hinkley Point C facility currently under construction in southwest England will comprise two reactors, each capable of generating 1630 MW of electricity. SMR components would be standardized and manufactured at central facilities before being assembled on site. While the first few SMRs would be expensive to build, standardized mass production would bring down the price of subsequent units – according to proponents of the technology.

Falling prices

This, says Rooney, is unlike conventional large-scale power reactors, which have become more and more expensive over the years. In his report he argues that SMRs offer a much more cost-effective way of generating electricity. “Each unit would require a smaller investment than large reactors and their modular nature means that they can be built in a controlled factory environment where, with increased deployment, costs can be brought down over time through improved manufacturing processes and economies of volume,” writes Rooney.

Rooney claims that SMRs would be useful for smoothing-out fluctuations in solar and wind-generated energy. He points out that shortfalls in solar and wind are a significant problem in the winter, when demand is high and the UK can experience week-long periods of weak sunlight and light winds. Such fluctuations could be smoothed-out using batteries, but Rooney claims that creating sufficient battery capacity would be extremely expensive.

Heat and hydrogen

The report also claims that SMRs offer flexibility in terms of the type of energy they produce. When renewable output is high, Rooney says that SMRs could switch over to producing hydrogen by the electrolysis of water. The hydrogen could be injected into the UK’s natural gas grid to reduce carbon dioxide emissions from domestic boilers and other gas appliances. He also points out that waste heat from an SMR could be used to heat local buildings.

In December 2017, the UK government announced that up to £100m will be made available for the development of SMRs. Rooney says that the government should move swiftly to develop at least one SMR under this initiative.


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