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Rocketdoc Notes – Week of February 7, 2021

Good Ideas

I ran across a number of good ideas for improving life in general this week so I thought I would list them and explain how they work and what to expect from them in the future. Most deal with our global warming problem and that’s where I will start.

Elon Musk’s $100 Million X Prize Challenge

Elon Musk, currently the richest person on the planet, has announced a four-year long competition to demonstrate a method for removing one ton of CO2 from the air or oceans per day that can scale to a gigaton per day. Fifteen teams will be selected for the competition within 18 months. They will each get $1 million, and 25 separate $200,000 scholarships will be given to student teams who enter. The grand prize winner will be awarded $50 million, second place will receive $20 million, and third place will get $10 million. This is serious money for a serious competition, and I would expect to see major players involved. In theory it should be possible to build an “artificial leaf” that could use sunlight to combine carbon dioxide from the air with water from an “artificial tree” to form sugar or simple fuels like ethane. I would expect to see several teams pursuing this cost-effective approach.

There are other CO2 capture efforts underway. For instance, Microsoft announced in 2020 that it wanted to capture the equivalent of all the carbon dioxide it’s ever emitted. The company pledged $1 billion toward the effort, and last month, we got the first glimpse at the progress Microsoft has made towards that goal. The company purchased contracts to capture 1.3 million metric tons of CO2, or just 11 percent of its total emissions for 2020 alone.

Nuclear Small Modular Reactor (SMR) Concepts

As I have mentioned in previous posts, the world needs a base energy source to augment the solar and wind energy renewables which are not available 100% of the time. Battery storage is mentioned as a possible baseload energy source, but if you run the numbers you see that that is not economical (you must oversize the renewables to charge the batteries which have very limited backup time capabilities). There has been significant advancement lately to reduce the cost and increase the safely of nuclear powerplants. Unfortunately, the U.S. government has not been at the forefront of this activity, so despite significant several billion dollars in private efforts in the U.S.A., the current reactor testing is occurring in China, India, Russia, and Canada, but not in the U.S.

The leading SMR contenders right now are NuScale and Terrapower in the United States and Terrestrial Power in Canada. NuScale is a pressurized water reactor similar to today’s large fission power-plants, only scaled down and modularized to allow it to be built in a factory, delivered by rail or truck, and assembled on site in less than four weeks. The idea is to install SMRs to replace the boilers in coal-fired powerplants as they are decommissioned but continue to use the same steam turbines, the same electric generators and the same power distribution systems. A NuScale 60 MWe power module is shown in Figure 1 below.

Figure 1 – NuScale Nuclear Power Module

In August 2020, the NRC issued a final safety evaluation report for NuScale's small modular reactor design, certifying the design as having met the NRC's safety requirements. NuScale plans to apply for a standard design approval of a 60-megawatt-per-module version of the design in 2022, which if accepted will allow the company to pursue its first reactor deployment in the mid-2020s.

Last fall, the U.S. Department of Energy awarded $210 million to ten projects to develop technologies for SMRs and beyond, as part of its Advanced Reactor Demonstration Program.

GE teamed with Terrapower LLC is offering to the DOE a system that replaces the pressurized water with molten salt. This reactor runs hotter than water-cooled reactors, but at normal pressure, which allows passive-cooling while improving safety by eliminating many pumps, valves, and a lot of plumbing. One feature of the Terrapower system is submerging the reactor core in a bath of molten salt which serves as an energy reservoir to generate additional steam and to allow extra power in excess of the reactor thermal power to be pulled from time to time. A cutaway view of the Terrapower SMR is shown in figure 2 below.

Figure 2 – Terrapower 100-Year Life Small Modular Reactor Cutaway

Our last example SMR startup is Terrestrial Energy of Canada. They just closed $8 million in funding from undisclosed sources for their proprietary Integral Molten Salt Reactor design, according to Security Exchange Commission documents. The small nuclear reactors are intended for industrial process heat markets, with market deployment targeted “in the 2020s.”

Also last year they entered a collaboration with Oak Ridge National Laboratory in Oak Ridge, Tenn. to develop the firm’s Integral Molten Salt Reactor (IMSR) technology to the engineering blueprint stage — and perhaps to regain some North American technological leadership in advanced nuclear power.

Oak Ridge National Laboratory (ORNL) built and operated the first molten salt reactor (MSR) in the late 1960s. It was a 7.4-megawatt (thermal) test unit, and its design was being considered for a nuclear-powered bomber. Terrestrial Energy’s reactor is based on ORNL’s denatured MSR design. The MSR is an advanced design in which the coolant is a molten salt, typically a fluoride salt mixture. In most designs, the nuclear fuel is dissolved in the coolant itself. MSRs run at higher temperatures and higher efficiencies than water-cooled reactors. Terrestrial Energy’s Integral Molten Salt Reactor is shown in figure 3 below.

Figure 3 – Terrestrial Energy Integral Molten Salt Reactor

TEI hopes to begin commercial deployment of its molten salt reactor technology by early next decade. The company claims that MSR technology provides improved safety and better control of waste and proliferation. TEI CEO Simon Irish has claimed that the reactor “will cost about the same to build as a coal power plant but will cost much less to run than a traditional nuclear plant.”

Terrestrial’s MSR is a modular design, able to range from 80 megawatts to 600 megawatts, and targeted at remote, military, or industrial sites, both on- and off-grid.

Using the small modular reactor (SMR) concept, reactors can be built in factories and shipped to the site already constructed, rather than being built — expensively and riskily — on site. Rather than engineer and build reactors capable of producing more than 1 gigawatt of electric power, SMRs can produce 10 megawatts to 6,000 megawatts of electricity (or heat).

SMRs are not a new concept. The U.S. Army has built and operated small nuclear power plants in the past, and the military continues to use small reactors to power naval vessels. But the incremental construction scheme of civilian SMRs aims to reduce financial and safety risks, though this has not yet been demonstrated. As far as MSRs are concerned, this is early days. Less is known about MSR designs compared to the knowledge gained from millions of operational hours of light water reactors.

But the regulatory challenge of MSRs could be more of an obstacle than the physics or finance. The Nuclear Regulatory Commission has regulated more than 100 reactors in the U.S., none of which are based on this design. It will require an enormous institutional adaptation to get this technology commercialized — and an enormous amount of funding.

In Rocketdoc Notes we have taken detailed looks at small modular reactors, including those from B&W, NuScale, Radix and Hyperion, fusion technology from General Fusion and Tri Alpha, and nuclear waste disposal from Kurion. We’ve reported on the Khosla- and Bill Gates-funded TerraPower. We’ve looked at the thorium fuel cycle, as well as the painful economic realities of nuclear plant construction. We reported on the first nuclear plant construction that the Nuclear Regulatory Commission has approved in 35 years! In 2014, the Department of Energy announced the availability of $12.5 billion in loan guarantees for advanced reactor designs or enrichment processes.

Nuclear provides 19 percent of U.S. electricity generation and is carbon-free in operation. It’s baseload power with a low price per kilowatt-hour, but it’s very expensive to build, and even light water reactors are already harrowingly difficult to finance. We need small modular nuclear powerplants to replace the current fossil-fueled baseload power systems to supplement our renewables sources and meet the Global Warming goals. Unfortunately, our government has been extremely slow in recognizing this fact.

I will cover ways of cooling the Earth next week.

Thanks for reading.

Dana Andrews

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