Nuclear District Heating Review

Several nuclear reactor concepts dedicated to low-temperature applications without any turbine cycle have also been developed, and the construction of two Chinese heating reactor prototypes (NHR200-II and DHR-400) is happening now or will start soon. If realized according to schedule, the technology could become commercially available in the 2020’s, which makes nuclear energy a potential option for reducing the CO2 emissions of district heating in Finland as well.

In November 2017 the China National Nuclear Corporation (CNNC) announced the development of a 400 MW pool-type DHR-400 heating reactor, after a successful 168-hour trial run using the “49-2” test reactor at the China Institute of Atomic Energy. The technology, sometimes referred to as “Yanlong”, is based on the earlier DPR studies. The first DHR-400 reactor unit has a construction license. In addition to district heating, the reactor is planned to be used for refrigeration and desalination of seawater, as well as material irradiation and isotope production.

There are also other non-electric uses for nuclear power.

Co-generation of heat and electric power becomes economically feasible when the generating station is located sufficiently close to a major population center. An IAEA report from 2000 lists 49 reactors in Bulgaria, Hungary, Russia, Slovakia, Switzerland and the Ukraine, that were primarily constructed for electricity production, but have also been used to serve district heating needs. The electric output of these reactors varies between 385–953 MWe, and heating capacity from 20 to 240 MW. Since high thermal efficiency for electricity production requires temperatures in the 300°C range, the supply temperatures for the district heating network are
also high, up to 150°C.

SOURCES- VTT Technical Research Centre of Finland, A Review of District Heating Reactor Technology, Leppänen, Jaakko. Perspectives on Non-Electric Use of Nuclear Energy. Harri Tuomisto, Fortum, Finland
Written by Brian Wang, Nextbigfuture.com

15 thoughts on “Nuclear District Heating Review”

  1. The NuScale reactor is inherently, walk away safe. You can leave it alone and it will sit there for decades and cause no problems.

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  2. Upvote for thermal desalination. Most desalination in the world today is thermal – as a cogeneration load at fossil plants. It is cheap, reliable, and safe.

    Cogeneration of electricity + desalination from nuclear makes more sense to me than dedicated plants for district heating. Electricity is a pretty good fuel for heating (and cooling) with heat pumps. 300%+ efficient heat pumps are widely available.

    If France had heat pumps (that also work as air conditioners) instead of nuclear cogeneration district heating, their heat waves would kill far fewer people.

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  3. It is not just low pressure it is no pressure, also, there is no tendency without control for it to escalate dramaticly. If it gets too hot the plug is disolved and the fluid leaves the reaction chamber and becomes diluted or spread out in a separate container.

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  4. Just because a reactor is designed for 3 atmospheres does not mean it stays at 3 atmospheres. Just means the vessel is not very strong. Molten salt does not have any natural tendency to go towards a run away reaction.

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  5. There was the SMAHTR molten salt reactor design to supply steam for tar sand oil recovery .

    If you don’t want to colocate the district heating reactor in the district though, being a low temp reactor really hobbles you. Low energy density means it’s not ideal to haul over long distances.

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  6. So what is the feature of a MSR that would make it superior to this?

    The safety issue that MSR supporters keep bringing up is that they run at very low pressures, but this system also runs at very low pressures so I’m not seeing the advantage.

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  7. My own suspicion is a lot of material use, still a lot of radiation to contain. I am guessing the economics of this, minus CP cash, are unattractive. So how would I fix this? To be honest, I’d use thermionic conversion from the lower heat and make use of it. Small units, less uranium needed, distributed, etc. So what would be better? I suspected wind and solar using some upgraded storage system.

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  8. I don’t think this reactor is a particularly practical idea, but at three atmospheres with clad fuel in a pool, it certainly has a much lower chance of release then a MSR which releases by design. Just saying…

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  9. I have mixed feelings about these things. I prefer reactors to be fairly distant from significant population centers. Conceivably, you could have some very well insulated pipes and longer runs, maybe something with a vacuum sleeve with the inner pipe suspended by low thermally conducting fibers. You would probably need pressure sensors in there and many chambers (analogous to segments of track) so one leak does not mess the whole system up.

    I like cogeneration for material refining/processing and manufacturing. And desalination is also a great use, though better at locations less susceptible to earthquakes and tsunamis.

    If it was a molten salt reactor, it would matter less if it was somewhat close to population centers. I would still be concerned about terrorism, war or any large aircraft crashes…most likely intentional. I’d hate to be a pilot of an aircraft unintentionally colliding with a reactor…no one would believe it was an accident in a million years.

    I am very pro nuclear power…I just like a bit of distance as a safeguard.

    If a molten salt reactor was under 50 feet of dirt and concrete, that should be pretty secure. A determined opponent in a war could still hit it…but they could just as easily drop a dirty bomb, so it makes no difference, I guess. It would certainly not be an accident if they hit it 50 ft down…that takes a bunker buster.

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  10. Perfectly reasonable water heater – says it is pressurized to 45 psi(g) and core inlet is 154F. I have questions about that design point…., but they know better. I calculate ~25Mlb/hr forced convection based on the enthalpy rise. It’s mPower, LOL, running with margin to boiling at atmospheric pressure – what a gas! mPower’s first incarnation was 69 FA 17×17 @ 6′ height with 25Mlb/hr forced flow, and ~40F temperature rise, but at 1900 psig.

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