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Comment by cwhiz | Hacker News Reader

I would like to see some models on how solar power could work in northern cities, or honestly any city. The NYC metro area has over 23 million residents and there is essentially zero space for a solar farm. In the winter it's cloudy almost all day and there are only 9 hours of sunlight.

Rooftop solar is an option but the models I have seen show a theoretical max around 1,200 MW which is about 1/30th of the NYC metro area electricity requirements.

I just don't see how solar is even close to being viable for anything outside of small cities with access to massive swathes of empty land.

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https://model.energy/

Generally, low latitude places want more solar + batteries, high latitude ones want more wind + hydrogen. When optimizing with these four, plus nuclear, with the costs at that site, nuclear typically optimizes to 0%.

Using their data for the UK (2011 weather) and the 2020 technology scenario (rather than the projections which conveniently make renewables and storage significantly cheaper and Nuclear costs constant) and requiring that the system be carbon neutral it only takes very small tweaks to their assumptions to make Nuclear a clear winner. They are assuming by default that countries will be able to use salt caverns for hydrogen storage, which seems unrealistic given the amount of it their scenarios require. Using the numbers they give for steel tank storage instead, it only takes a 5% cost reduction for nuclear (which seems self-evidently possible with economies of scale) to make the optimal solution a 100% nuclear grid.

Right now I don't think people are pragmatic enough for that to be politically viable in most western countries, but that may shift as the adverse effects of AGW start to be more acutely felt (and, hopefully, as more and stricter carbon taxes are implemented across the world).

Europe has like 100x the salt cavern capacity needed. Hydrogen can also be stored in deep aquifers or hard rock caverns.

Using the 2030 data is proper, since any nuclear reactor we begin to build today won't be available until about then (which renewable and storage systems can be built in just a couple of years.)

Some of their cost figures are already too high, btw. Their 2030 estimate for the cost of electrolysers was 600 euro/kW; it's already down to half that (or even less, in China).

You could imagine building a globe-spanning power distribution network. Solar panels on one side of the planet could provide power at night on the other side of the planet.

I bet the power transportation cost and loss would be too significant.

If we could transmit power across vast distances like that then we wouldn't even need to bother with solar. We could build a thousand nuclear power plants in the middle of nowhere.

Unfortunately, power transmission suffers from line losses. Even a few hundred miles requires several hundred thousand volts to avoid losses. Maybe that's an easier problem to solve than fusion.

You'd JUST need to move current from AC to DC, and span the whole of earth with superconductor cables.

You know, easy stuff to build and maintain.

Use the local electricity to crack water into H2 and O2. Release the O2, use the local electricity to compress the H2 into liquid hydrogen, pump in across the country. The pipes themselves are a storage facility.

China has built a 1100 kV line for 12 GW with losses of only 1.5% per 1000 km.

source: http://en.people.cn/n3/2018/0622/c90000-9474097.html

That's impossible, unless you have an invention for extremely cheap superconductors that you've been hiding away.

Electricity transport losses makes that impossible.

No I guess NYC needs to keep that nuclear power plant in Lower Manhattan then.

I know you’re saying this as if it should be something scary that I should oppose.

But I am not even remotely concerned about nuclear safety. If noise and traffic were no concern I would live right next to a nuclear power plant.

No I say this because if someone says solar is impractical in NYC and but nuclear somewhere else is, the comparison does not make any sense.

That isn't even the major electrical cost of supporting those people. The fertilizer needed to feed them, metal refining/recycling, chemical reagent production, shipping fuel, all dwarf the usage by individuals in their homes.

Personally I don't think solar is ever feasible for industrial scale work, covering like 1/3 of your landmass is a ridiculously large project and needed to fuel industrial operations that currently use fossil fuels to fuel them including fertilizer production. Even if you can shrink that down a bit, how much of it is competing for farmland? Or replacing natural forests or plains or other wildlife housing.

Where did you get 1/3? You dont need to cover even 0.001% of landmass to supply all of US!

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