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Matt Chester's picture
Matt Chester on Mar 11, 2021

Because, in the end, safety is not dependent on fancy gadgets or artificial intelligence, it’s more about fundamentally understanding physics and how materials behave

It's also just just about the safety but the proof and assurance of safety, which this type of testing availability provides. Such a great resource to the industry!

Emily  Nichols's picture
Emily Nichols on Mar 11, 2021

I agree Matt! It will be incredibly valuable to advancing technologies.

Jim Stack's picture
Jim Stack on Mar 12, 2021

We don't need any research. We already have lots of Carbon free energy in Solar PV, Wind , Hydro and Geo-Thermal . If we spent a tenth of the money on those real end to end carbon free and pollution free energy sources we would be done. 

  When you are looking at a reactor you have to account for the full system. The fuel and mining it, the transport of the fuel, the energy to built the reactor, the water you boil to make energy , the water you produce and the disassembly of the entire plant when you are done. Also include the entire cost with no subsidies . How long will the fuel be available too. The US now gets 90% of the uranium from Russia. 

Laura Scheele's picture
Laura Scheele on Mar 12, 2021

Hi Jim Stack, Thanks for your comment. There have been several lifecycle analysis of the carbon footprint from various fuel sources. Carbon Brief analyzed several of these studies and noted the findings of one published in Nature Energy:

The study finds each kilowatt hour of electricity generated over the lifetime of a nuclear plant has an emissions footprint of 4 grammes of CO2 equivalent (gCO2e/kWh). The footprint of solar comes in at 6gCO2e/kWh and wind is also 4gCO2e/kWh.

I agree that studies of lifecycle carbon emissions should take into account the energy return on investment (EROI) and rebound effects with new energy sources, and state any forward-looking assumptions that are made. These factors should be maintained across the spectrum of fuel sources. As you note, manufacturing and the supply chain also matters (from the link above): 

Factories churning out solar panels use large amounts of electricity, often sourced from coal-fired power stations in China. Wind turbines and nuclear plants need a lot of steel and concrete. And the centrifuges that separate nuclear fuel also rack up a big electricity bill.

There's a lot of promise in using advanced nuclear technologies to produce not only electricity, but to use process heat and steam for production of hydrogen and other industrial resources that currently are produced using fossil fuels. As we see those applications being deployed, we'll also see corresponding declines in carbon emissions for other, non-utility sectors. Nuclear energy will have a role to play in a carbon-free energy mix.

 

 

 

 

 

Mark Silverstone's picture
Mark Silverstone on Mar 16, 2021

Thanks Laura.

The study finds each kilowatt hour of electricity generated over the lifetime of a nuclear plant has an emissions footprint of 4 grammes of CO2 equivalent (gCO2e/kWh). The footprint of solar comes in at 6gCO2e/kWh and wind is also 4gCO2e/kWh.

I think the figures you quoted for carbon emissions are a bit misleading, especially when considering the data from the source publication.

Most studies give a range of carbon emissions per kwh generated.  The ranges are broad,  making it very difficult to pin down any comparison.  In addition,  the source of the numbers cited are somewhat speculative, at best, as described in the Carbon Brief article:

«...this chart shows figures for a 2C world in 2050, when global electricity supplies have been largely decarbonised. This shift cuts the impact of indirect emissions due to electricity use, for example at a solar cell factory or nuclear fuel site.»

Also, as explained in the article, variation depends to quite a large degree on location:

«Note that the global average figures in the chart, above, hide wide geographical variation for some power sources, particularly hydro and solar.

The best solar technology in the sunniest location has a footprint of 3gCO2/kWh, some seven times lower than the worst solar technology in the worst location (21gCO2/kWh). Even at this top end, however, solar’s footprint is very low compared to other sources.»

Even the World Nuclear Association, never shy to tout nuclear, however nonsensically, as it describes nuclear waste, lists ranges for different power technologies:

No discussion of CO2 emissions with various forms of electricity generation would be complete without reference to the highly detailed Stanford studies:

Here, nuclear clearly takes a back seat, especially to solar and offshore wind.

It is tempting to simply say that nuclear and renewables are all far lower than fossil fuels, including coal with CCS (“…the study assumes that CCS only captures 90% of power plant CO2”), and leave it at that. But because of the large ranges for the carbon intensities for different power sources,  I suggest that the choice of power generation in a particular place and time needs to take into account where on the range of emissions a particular project might be.  Hydro especially, may turn out to be in the upper range and result in higher emissions than might be expected.  Hydro that does not require a dam or much storage of water may be on the lower range of emissions.  Therein may be the niches for nuclear.

I would add that the emissions from disposal of nuclear waste are not included in any of these approximations, since there is, so far, no such thing as final disposal of nuclear waste.  I can only guess that it won´t be trivial. Nor is any estimate inclusive of small nuclear power plants, SMRs, as they do not yet exist either.  I have seen no estimate of life cycle GHG emissions from those.  Presumably, they would result in higher emissions per kwh as they are smaller and more of them would be necessary.

I fear that at least part of the objective of the versatile test reactor program may be similar to the approach for the defense department´s F-35 multi-role fighter plane. Once enough money is spent, it becomes “too big to fail”. Heaven help us if that mentality takes over.

 

 

 

 

Michael Keller's picture
Michael Keller on Mar 17, 2021

Has been my experience that industrial process heat employs saturated steam at relatively modest pressures. Also, need low-cost steam and that pretty much rules out using a nuclear reactor. Hydrogen production needs low cost electricity and/or steam, again pretty much ruling out using a nuclear reactor.

Seems to me the nuclear industry is engaging in a lot of marketing hype  to try and convince folks to go along with nuclear power. The main driver should be economics and not climate change conjecture. I would use the same admonition with green energy. The point ultimately being use the right energy source in the right place. That mix is highly dependent on location and available resources. One size does not fit all, which kind of echos Marks observations.

Audra Drazga's picture
Audra Drazga on Mar 16, 2021

Jim, food for thought - Solar and Wind also require and need mining of resources and have some disposal issues as well.  

Michael Keller's picture
Michael Keller on Mar 16, 2021

The versatile test reactor’s primary function is to create jobs in Idaho. The technology is only technically useful to support development of fast reactors whose economic value for power production is essentially zero. The fast reactors recycle nuclear fuel, but at stunning costs. Much more cost effective to use the fuel once and put it in deep quarantine to (1) prevent  clandestine weapons manufacture and (2) keep it away from the population.

Emily  Nichols's picture
Emily Nichols on Mar 18, 2021

Hi Michael Keller,

Thanks for the comment. The Department of Energy hasn’t decided the location of the Versatile Test Reactor yet. Idaho has been identified as a preferred location with Tennessee (Oak Ridge National Laboratory) being an alternate location. A final decision is expected later this year.

 The proposed Versatile Test Reactor would be a sodium-cooled fast reactor and would be used for R&D to support development of advanced reactors, including fast reactors. There are several fast reactors under development today for both power production and use of process heat and condensed water vapor. Let’s remember that today’s U.S. light water reactor fleet produces more nuclear-generated electricity today with fewer reactors than 20 years ago – and that R&D in test reactors is one of the drivers behind increased capacity factors and uprates.

 Although you challenge the economics of this reactor type, many experts in the field disagree with your assertion. Here’s one example from Forbes writer Scott Carpenter:

Now a firm launched by Bill Gates in 2006, TerraPower, in partnership with GE Hitachi Nuclear Energy, believes it has found a way to make the infamously unwieldy energy source a great deal nimbler — and for an affordable price. 

 The new design, announced by TerraPower on August 27th, is a combination of a "sodium-cooled fast reactor" — a type of small reactor in which liquid sodium is used as a coolant — and an energy storage system. While the reactor could pump out 345 megawatts of electrical power indefinitely, the attached storage system would retain heat in the form of molten salt and could discharge the heat when needed, increasing the plant’s overall power output to 500 megawatts for more than 5.5 hours. 

“This allows for a nuclear design that follows daily electric load changes and helps customers capitalize on peaking opportunities driven by renewable energy fluctuations,” TerraPower said. 

Dubbed Natrium after the Latin name for sodium ('natrium'), the new design will be available in the late 2020s, said Chris Levesque, TerraPower's president and CEO.

Appropriate care and caution will be taken with VTR waste streams. Used fuel from the Versatile Test Reactor (VTR) must be processed and secured in storage containers to minimize the risk of radioactive materials escaping into the environment. The majority of waste generated by VTR is used fuel and the steel hardware that encases the fuel in the reactor core.  Small amounts of liquid waste and sodium (used for bonding the fuel) that are generated during normal operations will be treated.

Fortunately, the volumes are small. The used fuel and waste from VTR is expected to fill one commercial used-fuel canister every two years—or approximately 30 canisters over the reactor’s 60-year life span.

Again, thanks for your comments. I welcome you to visit https://inl.gov/vtr for more information.

Michael Keller's picture
Michael Keller on Mar 17, 2021

Your data looks pretty suspicious, particularly when terms like “opportunity cost” show-up (typical buzz word used by manufacturing information that is difficult to actually quantify).

That being said, I do agree with your assessment of the test reactor.

Jim Stack's picture
Jim Stack on Mar 19, 2021

Laura, The amount of energy and material to build a Nuclear facility is hundreds of times more than making a Solar panel or wind generator. When adding the life of Nuclear you also have to add in the waste left over, the shutdowns for refueling and transporting and mining the Uranium. It also takes a lot of energy to turn the uranium into fuel rods. There would never be one Nuclear plant built if there were no subsidies for them. They are the most expensive energy ever made. It' s lot more than simple CO2. 

Michael Keller's picture
Michael Keller on Mar 19, 2021

You appear to have overlooked the fact that to produce the same amount of energy as on nuclear power plant, you need a few thousand green energy facilities (due to low output and poor capacity factor). Tend to end up with more concrete and steel than the nuclear plant using wind turbines. Solar, not so much, but need a lot of land as well as somewhat exotic material fo the thousand of solar panels.

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