Rolls's reactors are designed to produce 220 megawatts (MW) of power, but this can be scaled up to 440MW. By comparison, Hinkley's traditional desing is expected to generate 3.2gigawatts (GW).

Rolls says it sees a UK demand for SMRs of 7GW and a global market of between 65GW and 85GB over the next two decades, which is estimated to be worth between £250bn and £400bn.

“Government is supportive of this technology and this is an opportunity to change the whole paradigm of technology from importing expertise into Britain to exporting it from this country,” said Mr Holt.

He added that with most of the major markets for SMRs outside Europe, the technology could be a vital part of any "Brexport" campaign to secure trade ties with countries beyond the EU.

The consortium believes that it will cost £1.2bn to develop SMR technology fully and a further £1.7bn to get the first SMR running. Costs are then forecast to fall as more are built, with the modular design meaning that the system is built in “chunks” in factories, then assembled on-site.

This means they will be quicker to build than conventional "bespoke" designs such as Hinkley, as well as cheaper as they are being mass-produced by comparison. Their lower price-tag will also make them easier to finance.