Modular nuclear reactors promise cost-competitive hydrogen production

Modular nuclear reactors promi...
Artist's concept of a NuScale reactor installation
Artist's concept of a NuScale reactor installation
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Artist's concept of a NuScale reactor installation
Artist's concept of a NuScale reactor installation
Diagram of a NuScale Power Module
Diagram of a NuScale Power Module
An NPM (right) alongside a conventional nuclear containment vessel for scale
An NPM (right) alongside a conventional nuclear containment vessel for scale
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NuScale Power has released the results of a new evaluation that indicates that a single small nuclear NuScale Power Module (NPM) could economically produce almost 50 tonnes of hydrogen fuel per day. The study, originally conducted by the Idaho National Laboratory, says that the improved power output of the NPM allows it to produce 20 percent more hydrogen from water than previously.

The prospect of a hydrogen economy suggests a promising alternative to conventional power sources based on fossil fuels. For example, a hydrogen-powered motor car that burns the gas in a fuel cell to create electricity would have the eco-friendly, zero-emissions footprint of an electric car, but without the need for the eco-unfriendly battery banks, the slow charging times, and limited range.

However, a hydrogen infrastructure suffers from one major snag. Unlike fossil fuels, hydrogen doesn't exist in tappable deposits like natural gas. It has to be extracted from more complex molecules using large amounts of energy. In fact, 95 percent of the hydrogen produced in the world today comes directly from fossil fuels, with the biggest supply coming from steam methane reforming, where a mixture of steam and methane gas is put under high pressure while in contact with a nickel catalyst, to produce hydrogen, carbon monoxide and a small amount of carbon dioxide.

Diagram of a NuScale Power Module
Diagram of a NuScale Power Module

Around the world, scientists and engineers have been looking at ways to get around this by creating new catalysts or ways to split water into its component hydrogen and oxygen molecules using sunlight to either power an electrolysis process or to provide heat to crack the water molecules apart at high temperatures. The problem is that solar hydrogen plants can only work on a sunny day, don't scale well, and have a massive real estate footprint.

One plant proposed by the University of Colorado, for example, would use five 732-foot-tall (223-m) towers illuminated by 21.5 million square feet (two million sq m) of heliostat mirrors in a plant covering 1,200 acres (485 ha). For all that, it would produce 100 tonnes (222,400 lb) of hydrogen per day.

Those figures suggest the solar plant is twice as productive as an NPM, but NuScale says that its nuclear modules are designed to scale up by adding as many of the factory-built nuclear reactors as needed at a site. According to the new study, a single module generates 250 MW of heat or 77 MW of electricity. One, five, a dozen, or more such reactors could be installed on a site smaller than a conventional power station and located almost anywhere.

An NPM (right) alongside a conventional nuclear containment vessel for scale
An NPM (right) alongside a conventional nuclear containment vessel for scale

The method that NuScale uses to produce hydrogen is based on superheated steam and electricity. Water is heated to a temperature of 300 °C (572 °F) by the reactor and then the temperature of the steam is increased to 860 °C (1,580 °F) using two percent (around 1.8 MW) of the reactor's electrical output. This is then put through a high-temperature steam electrolysis system that works like a fuel cell in reverse. By pumping thermal energy into the system, the water breaks up into hydrogen and oxygen rather than combining the gases into water to get out energy.

According to NuScale, the process is cost competitive and by using nuclear reactors that also generate electricity, the small modular reactors can be switched into and out of hydrogen production as the demand for electricity fluctuates. In addition, the Oregon-based company estimates that a single NPM would reduce carbon dioxide emissions by 168,000 tonnes per year.

NuScale did not explain why a small nuclear reactor should be used for hydrogen production rather than a larger conventional reactor, but it's likely a matter of economics where a small reactor could affordably be purposed for hydrogen production where a larger and more expensive reactor couldn't be.

"The ability of our NPM to now produce even more clean hydrogen, in a smaller footprint, is yet another example of how NuScale’s technology can help decarbonize various sectors of the economy while providing additional revenue streams for customers," says Dr. José Reyes, Chief Technology Officer and Co-founder of NuScale Power. "Coupled with our proven design, unparalleled safety, and load following capabilities, this analysis further demonstrates that NuScale’s design is the gold standard in helping meet the demand for innovative solutions to challenging global energy needs."

Source: NuScale Power

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Reynold Reimer
Why is there no mention of the waste produced by the reactor. It would be extremely toxic and extremely long lived. In what way is this better than burning coal?
Also there's no mention of the nuclear industry's propensity to mis construction time deadlines and budget projections.
We don't have time to wait for the nuclear industry to clean up its act. We need to transition to renewables starting yesterday.
Bob Stuart
Wow! A double-barrelled boondoggle! Nuclear power has never been cost-competitive. The industry's latest lie is that they should have mass produced the original reactor sizes instead of scaling up like other industries do. There is still no hint of a solution to the near-eternal biohazards produced which spread like a stain even with the best containment budgets. Then, the hydrogen is terrible as a portable fuel. It is bulky, dangerous, and leak-prone, while making any steel containers brittle. This project is guaranteed to prolong the climate crisis, not help it.
It is extremely bad idea to use hydrogen as fuel or energy storage because it is explosive! Much more dangerous than gasoline or natural gas etc!
You seriously think there would be never any leaks or ruptures that can easily end in a massive explosion?

Electric cars do not need hydrogen!
& for heavy trucks & ships (even aircraft), it would be best to start producing biodiesel (which is extremely hard to catch fire & can be produced from many kinds of crops/biomass (maybe even trash))!
Jeff A
Author wonders why the small reactor for hydrogen. I’m betting the 250 megawatts of waste heat for the 77 megawatts of electricity is the reason. They have been promising these small modular reactors for years, but apparently need to make hydrogen to make the economics work. Note the first installations in the west have had some of the small utilities bail due to cost. I can’t think of a process that gets more efficient when you scale it down.
The hydrogen economy is something that refuses to die. As Bob Stuart has pointed out,H2 is a flawed fuel. After it is produced,it has to be compressed for storage and transported to where it is needed,which introduces large losses. If the Toyota Mirai FCEV is anything to by,FCEVs are produced at a considerable loss,and the fuel cells themselves have a limited lifespan,and would be expensive to replace. Refueling FCEVs requires the building of 10s of thousands of H2 filling stations nationwide. Who is going to pick up the bill for that? Government? Certainly not private industry. With no demand for H2,a business would be insane to invest in building a refueling infrastructure. BEVs have won the battle,as you can refuel anywhere there is an electrical outlet.
I've long thought small scale nuclear was a solution that is highly overlooked, due to the perceptions listed by others. Small scale like this is inherently much safer (no 3 mile island or Chernobyl like incidents possible), and can be located closer to end use. Large scale high risk plants have to be farther away from cities, increasing transmission costs as well. The high costs of large scale plants are due to all the extra redundancy, governmental requirements, and wasted engineering time. Companies that make them spend a lot of time in engineering, for projects that never see the light of day, and that money gets recouped by projects that get done. I'm very excited to see how NuScale and other companies going this route perform. While I do like the concept of hydrogen economy, I think the logistics are a problem. I think using the energy from these plants would better serve the bio-fuel industry, in making carbon neutral gasoline, natural gas (methane) and diesel alternatives
Peter Stegmeier
i have no problem with hydrogen as an energy source, what i have is a real fear of people that think using earths water supply to run our toys is a good idea, its right up there with those who think building machines smarter than we are is a great idea.
Wow the trolls are really out on this one. Looks like an incredible solution to me. Electricity to run all those EV's has to come from somewhere. There is no magic.
Are there any applications submitted for permits for this small nuclear reactors or they are just conceptual proposals? If they have not made a well working and permit ready prototype yet, this will never happen in our time or it is just a pipe dream that some investors are paying for to be dreamed of.
Such a lot of negativity in the early comments! I'm willing to give the economics a chance here, provided there is no subsidy -- including no subsidy on the issue of waste disposal. The so called renewables DO NOT pass this test.
On the subject of waste disposal, there is a lot more emotion than logic in the public. Despite public perception, nuclear waste can be safely disposed.