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The New, Safer Nuclear Reactors That Might Help Stop Climate Change

The urgent need to cut down coal consumption has forced many policymakers and environmental groups to conclude that nuclear energy is the way to go. Previously reticent, United Nations researchers now agree that every plan to keep the planet’s temperature rise under 1.5 °C will rely on a substantial increase in nuclear energy.

But presently, the prevailing trend is different. Germany intends to shut all its nuclear plants by 2022 while Italy blocked any future projects back in 2011. Furthermore, nuclear lacks broad public support and is so expensive that several nuclear plants in the US were decommissioned recently because they can’t compete with cheap shale gas.

The Union of Concerned Scientists, argued, “If the current situation continues, more nuclear power plants will likely close and be replaced primarily by natural gas, causing emissions to rise.”

He has a point as estimates suggest that if all those plants shut down, carbon emissions would increase by 6%.

Edwin Lyman, acting director of the UCS’s nuclear safety project, says, “At this point, the critical debate is not whether to support existing systems. A more practical question is whether it is realistic that new nuclear plants can be deployed over the next several decades at the pace needed.”

 

Three reasons for renewed hope for nuclear power

Small modular reactorsAdvanced fissionFusion
SMRs are a slimmed-down version of conventional fission reactors. Although they produce far less power, their smaller size and use of off-the-shelf components help reduce costs.These reactors are designed to be safer than traditional water-cooled reactors, using coolants such as liquid sodium or molten salts instead. Most advanced is the “pebble bed” reactor, cooled by a gas such as helium; China is ready to connect the first such reactor to the grid this year.Technical progress is still slow after decades of investment, but fusion companies are focused on how to contain the plasma required to replicate the thermonuclear conditions of the sun. Techniques include magnetic confinement, which traps plasma continuously at low pressure; inertial confinement, using lasers and pulsing plasma for nanoseconds at a time; and magnetized target fusion, which combines the two with pulses of plasma controlled by magnets.
CompaniesNuScale PowerChina National Nuclear Corporation, TerraPower, Terrestrial EnergyITER, TAE Technologies, General Fusion, Commonwealth Fusion Systems
Power output50-200 megawatts190-600 megawatts100-500 megawatts
Expected life span60 years40-60 years35 years
Cost$100 million prototype,
$2 billion to develop
Pebble beds: $400 million to $1.2 billion
Sodium-cooled and molten salt: $1 billion prototype
ITER: currently $22 billion
Cost of a commercial version is unknown
Available2026Pebble bed in 2019; sodium-cooled 2025;
molten salt 2030
No earlier than 2035

 

According to the think tank Third Way. in early 2018, there were 75 separate advanced fission projects in North America alone. These projects use the same type of reaction fission i.e. splitting atoms, that was employed in the conventional nuclear reactors that have been used for decades. One of the leading technologies among these is the small modular reactor aka SMR which is a slimmed-down version of conventional fission systems expected to be cheaper and safer. NuScale Power which is based in Portland, Oregon, has a 60-megawatt design and about to get deployed.

Image result for nuscale

NuScale has bagged a deal to install 12 small reactors to supply energy to a coalition of 46 utilities spread across the western US, but the project will proceed only if the group’s members agree to fund it by the end of this year. While NuScale’s approach consumes traditional light-water-cooled nuclear reactors and shrinks them into so-called generation IV systems use alternative coolants. China is also building a large scale sodium-cooled reactor in Fujian province scheduled to begin operation by 2023, while Washington-based TerraPower is developing a sodium-cooled system that can be powered with spent fuel like depleted uranium, or uranium extracted out of the ground. TerraPower which has Bill Gates as an investor has forged an agreement with Beijing for the construction of a demonstration plant by 2022 but its future is questionable considering the political narrative.

Another generation IV variant, the molten-salt reactor, is considered safer than earlier designs because it can cool itself even when the system loses power completely. Canadian company Terrestrial Energy intends to build a 190 MW plant in Ontario with the projected first production of power before 2030 at a cost that’s competitive with natural gas.

One generation IV reactor could also go into operation soon. Helium-cooled, very-high-temperature reactors can run at up to 1,000 °C, and the state-owned China National Nuclear Corporation has a 210 MW prototype in the eastern Shandong province scheduled to get connected to the grid this year.

Many believe nuclear fusion is a great energy hope. Fusion reactors replicate the nuclear process inside the sun by smashing lighter atoms together to turn them into heavier ones by releasing vast amounts of energy. In the sun, this exothermic process is powered by gravity but on Earth, engineers aim to mimic fusion conditions with incomprehensibly high temperatures about 150 million °C but they are unable to confine the plasma required to fuse atoms.

Image result for iter

ITER, previously called the International Thermonuclear Experimental Reactor is a solution and is under construction since 2010 in Cadarache, France. Vancouver’s General Fusion has used a combination of physical pressure and magnetic fields to generate plasma pulses that last millionths of a second. This approach is less complicated than ITER’s, far cheaper as well but technical challenges of viable titanium components remain. California-based TAE Technologies has developed a fusion reactor over the last 20 years, that converts energy directly into electricity and may become commercial in 5 years.

General Fusion CEO Chris Mowry contends that fission simply has too many blockades to be successful. As the founder of mPower, the SMR company that was suspended in 2014, he speaks from experience. He suggests fusion reactors might be harder to build, but they are definitely more socially acceptable. He says this is why there’s been a rush of venture capital into fusion, because investors are confident there will be a sea of eager buyers waiting for whoever can make it work first.

Advanced fission will reduce nuclear waste by using it as fuel and drastically reduce the chance of nuclear tragedies like Fukushima or Chernobyl. Even then, no such reactors have been licensed or deployed outside China or Russia.

But does fusion really have that much more room to maneuver? The low-level, short-lived radioactive tritium waste produced by it represents no serious danger, and the technology proves that meltdowns are impossible. But expenses are still high and timelines very long. ITER’s fusion reactor is enormously more expensive than originally planned and still won’t be workable for another 15 years. In the meantime, Green politicians in Europe are already calling for ITER’s shut down as many anti-nuclear campaigners don’t even distinguish between fission and fusion.

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