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Comment by bungle | Hacker News Reader

> First of all, a lot of gas gets used for heating - nuclear isn't useful there

All electricity basically turns to heat at some point. So why not?

You lose something like 70% of the thermal output of the reactor in the conversion to electricity. Also the capacities a nowhere near large enough. Nord Stream 2 alone can transport something like 63 GW worth of gas. This is more than the total electricity consumption of Germany.

And for a home heater, 80% of the heat from the gas you burn goes up the chimney.

Larger energy capture devices can be more efficient. One highly-efficient fuel burning plant providing power to a hundred thousand electric resistive heaters can produce more useful heat per unit fuel than a hundred thousand small-scale self-maintained home furnaces.

I think you got your numbers wrong. Even in the US, you are not allowed to sell gas furnaces with less than 80% efficiency. High-end ones reach over 99% efficiency.

Your numbers are totally off. When did you bought and installed the last heater?

Modern condensing heaters have an efficiency of 90%.

You're both wrong.

Combined cycle power plants can be 64% efficient [1] at turning heat into electricity. And if that power goes on to run a heat pump, 1 watt of electric power can deliver 3-4 watts of heating.

And modern gas combi boilers can be 92-98% efficient [2].

The days of people throwing away 80% of the energy they pay for are long gone.

[1] https://en.wikipedia.org/wiki/Combined_cycle_power_plant [2] https://www.which.co.uk/reviews/boilers/article/boiler-energ...

Could you give some examples for nuclear power plants that are using a combined cycle turbine? I was under the impression that the operating temperatures of BWRs or PWRs are nowhere near high enough for that.

Maybe because 90%* of all houses need to be refitted.

(*estimated number out of thin air, but yes majority is gas or oil)

In the UK, air source heat pumps are pushed as a 1:1 replacement, with running costs basically the same as gas, in GBP.

I can’t verify that easily, but this doesn’t seem disputed, so the retrofitting is maybe not so much of an issue. There is of course the initial installation cost, but also presumably lower maintenance costs.

Yes, of course you can heat with electricity - and using heat pumps this is definitely the future. However, the amount of nuclear available would make only a small difference here. It should be much easier to just buy gas internationally and push forward with renewables.

You can also use the heat directly (district heating) without having to go to electricity and back. This limits the electricity output efficiency but increases the overall efficiency of the plant. It requires changes to the turbines and the buildout of a district heating system though.

Sure you could heat with nuclear directly. Actually that sounds like something that should have been done when nuclear was in fashion. But you would have to produce a lot of new infrastructure and most of all, new nuclear plants. None of the existing nuclear plants is suitable for that.

And that is sure, while keeping the remaining nuclear power plants in service a little bit longer might be a consideration (though unlikely), investing in new nuclear infrastructure for sure isn't. There, renewables are the way to go.

Germans can barely get their heads around nuclear energy. Pumping fluids that have been anywhere near a reactor into homes will be untenable.

I don't think this is the core problem, that would have been to build a nuclear reactor so close to a major city, that you could run a pipe to it.

As you can tell from the map that's not really an issue. Nuclear power plants aren't in the middle of nowhere, they need access to an educated workforce.

https://www.researchgate.net/figure/The-map-of-Nuclear-Power...

They aren't in the middle of nowhere, but usually quite a bit away from city centers, for safety reasons. Too far for a hot water line to be practical.

Up to 30km is no problem for water between 90-175 degrees celcius, so you reach plenty of cities.

https://doi.org/10.1016/j.apenergy.2018.02.080

SMRs operating at atmospheric pressure, or otherwise more managable due to smaller scales may alleviate that.

https://waerme.hamburg/presse-media/pressemitteilungen/erneu... <- This is one such plant at the western edge of Hamburg, being remodeled for that use-case. Having recently seen workers from Statnett climbing the masts in the rain to put pilot wires to pull new wires(80MW upgrade) on one half of the masts, while hearing the 50hz-buzz about 25 to 30 meters below. Crazy Vikings! :-)

You can't use electricity to run your gas furnace.

Green hydrogen derivatives would make that theoretically possible. This is receiving quite a lot of attention in the EU at the moment. In practice, the stress is more on industrial processes and other primary energy use scenarios.

https://waerme.hamburg/presse-media/pressemitteilungen/wasse...

But if you use that gas furnace to heat radiators in a fluid-born (usually water) heating system, you only need to install an electric heater next to your furnace and re-route the pipes to/from the furnace to use that heater in stead. Not all that humongous an operation.

Nobody here uses electrical heating. It's all done with radiators and the like, pretty much exclusively.

https://news.ycombinator.com/item?id=30439403

And heat pumps work much better than induction generally.

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