Rolls-Royce has announced that it plans to build, install, and operate up to 15 mini nuclear reactors in Britain, with the first set to go online in nine years. In a BBC Radio 4 interview with business journalist Katie Prescott on January 24, 2020’s Today program, Paul Stein, chief technology officer for Rolls-Royce, said that the company is leading a consortium to produce factory-built modular nuclear reactors that can be delivered for assembly by ordinary lorries.

Currently, the world is undergoing a boom in nuclear power. According to the World Nuclear Association, there are 448 operating civilian reactors and another 53 under construction. However, almost all of these are being built in Eastern Europe and Asia, with China alone building more reactors than the entire Western world combined.

Part of the reason for this is political with every reactor program in Europe or North America facing implacable environmentalist opposition and part of it is the expense of building and operating large reactors in an energy economy now dominated by cheap natural gas. However, one technology trend that could reverse this stagnation is the development of small, modular nuclear reactors that could be mass-produced in factories, carted to the site by ordinary lorries, and then assembled to generate cheap carbon-free electricity.

This approach, too, has its drawbacks, but Rolls-Royce believes that its consortium has got its sums right and can restart Britain’s nuclear industry by building up to 15 Small Modular Reactors (SMR) with an expected value to the UK economy of £52 billion (US$68 billion), another £250 billion (US$327 billion) in exports, and 40,000 new jobs by 2050.

Each power station is projected to have a service life of 60 years and generate 440 MW of electricity, or enough to power a city the size of Leeds. The estimated cost of the electricity generated is £60 (US$78) per MWh.

https://newatlas.com/energy/rolls-royce-plans-mini-nuclear-reactors-in-britain/

Good

but are they thorium fed

“Currently, the world is undergoing a boom in nuclear power. “

SCIENCE said:

but are they thorium fed

If they can be made to work, thorium reactors are safer than other designs.

Tamb said:

SCIENCE said:

but are they thorium fed

If they can be made to work, thorium reactors are safer than other designs.

… or so some people say.

The Rev Dodgson said:

Tamb said:

SCIENCE said:

but are they thorium fed

If they can be made to work, thorium reactors are safer than other designs.

… or so some people say.

Any assessments of their safety would be theoretical, as there are no thorium reactors anywhere now.

dv said:

Good

Agree. I really hope they don’t encase them in 20 m thick concrete designed to repel a nuclear bomb. That’s overkill.

Picture of my favourite mini-nuclear-reactor.
(can’t find picture easily, it’s the size of a basketball).

Picture of my second-favourite mini-nuclear-reactor

dv said:

Good

Agree. I really hope they don’t encase them in 20 m thick concrete designed to repel a nuclear bomb. That’s overkill. They did that with the reactor in the following picture.

Picture of my favourite mini-nuclear-reactor.

SCIENCE said:

but are they thorium fed

Actually, from what I’ve been reading in the past few days it that the best design of all is MOX fuel.

MOX can be used to extract all the energy from uranium, not just 5%. It can accept depleted uranium as fuel. It can take plutonium from dismantled nuclear weapons.

https://en.wikipedia.org/wiki/MOX_fuel

“Mixed oxide fuel, commonly referred to as MOX fuel, is nuclear fuel that contains more than one oxide of fissile material, usually consisting of plutonium blended with natural uranium, reprocessed uranium, or depleted uranium. One attraction of MOX fuel is that it is a way of utilizing surplus weapons-grade plutonium, an alternative to storage of surplus plutonium. Reprocessing of commercial nuclear fuel to make MOX is done in the United Kingdom and France, and to a lesser extent in Russia, India and Japan.”

“About 30 thermal reactors in Europe (Belgium, the Netherlands, Switzerland, Germany and France) are using MOX and an additional 20 have been licensed to do so. Most reactors use it as about one third of their core, some will accept up to 50% MOX. About 30% of the plutonium originally loaded into MOX fuel is consumed by use in a thermal reactor. If one third of the core fuel load is MOX and two-thirds uranium fuel, there is zero net gain of plutonium in the spent fuel.”

Thorium reactors are considered good only because they produce fewer “lesser actinides” such as americium. Americium (the stuff in smoke detectors) is considered a difficult component of nuclear waste. By using plutonium quickly in MOX fuel hardly any americium is produced. And MOX reactors can even accept and destroy americium.

PermeateFree said:

Rolls-Royce has announced that it plans to build, install, and operate up to 15 mini nuclear reactors in Britain, with the first set to go online in nine years.
…
Each power station is projected to have a service life of 60 years and generate 440 MW of electricity, or enough to power a city the size of Leeds. The estimated cost of the electricity generated is £60 (US$78) per MWh.

https://newatlas.com/energy/rolls-royce-plans-mini-nuclear-reactors-in-britain/

> there are 448 operating civilian reactors and another 53 under construction. However, almost all of these are being built in Eastern Europe and Asia, with China alone building more reactors than the entire Western world combined.

Interesting.

Found the specs. https://www.rolls-royce.com/~/media/Files/R/Rolls-Royce/documents/customers/nuclear/smr-technical-summary.pdf

In the cutaway diagram at right, red is the nuclear reactor area, yellow is the turbine room and blue is the cooling water pump. In the diagram at left, the centre bottom cylinder is the reactor and the three pills with tails around the top are hot and cold running water.

With a reactor height of 11.5 metres and diameter of 4.3 metres, it’s not what I’d call a mini-reactor.
The cooling water inlet has a temperature of 293 Celsius, which is somewhat hotter than I expected.