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by sir_bearington 1943 days ago
Yes, nuclear hardly costs any more to run at 100% capacity than it does at 50% capacity. That's why decarbonization with renewables as a primary source doesn't make much sense.

Solar and wind are both intermittent. Wind is dependent on the weather and experiences situations with near zero production for long stretches of time. Solar is also weather dependent, and has day-night cycles on top of it.

This is fine if you're not actually looking to decarbonize a grid, just trying to opportunistically shave off carbon emissions here and there in a primarily fossil fuel grid. But if you're actually trying to eliminate fossil fuel use this is not a good approach. Theoretically we could store excess energy, but no scalable storage solution exists at the moment. That leaves nuclear power plants to serve as a dispatchable source. But as you pointed out, nuclear plants are just as cheap to run 24/7 as it does to run intermittently. So why not just build the nuclear plants and skip the renewables?

1 comments

The issue as I see it is that pretty much nobody is looking at decarbonizing a grid, money be damned.

Unless your power production is run by the government, generation is done by companies looking to make a profit. Solar and wind companies don't mind in the slightest that they're screwing up the business model of nuclear. The fact that their production is intermittent isn't important to them -- it's already accounted into their business model, and nuclear's lack of ability to deal with that and grid stability is somebody else's problem.

If you think nuclear is the solution here you must be prepared to pour many billions of tax money on supporting its existence even though it's currently unprofitable. China can do that, because China's government has the long term control and lack of concern about public opinion to get such things done.

Politicians in democratic nations in general lack such a luxury. They know that they can get kicked out of power before their first plants get built, and then the successor either pulls the plug on the project entirely, or keeps whatever got built, but almost definitely nowhere near close to the full capacity needed.

You'd have a hard time skipping the renewables, because you'd essentially have to forbid them. You'd have to go there and make a law that you can't build solar even though it would produce power that's twice as cheap, or take craploads of tax money and subsidize nuclear. I suspect neither is going to look very good in the news.

Introduce carbon taxes and all of a sudden nuclear becomes a lot more viable. Existing plans for renewables are for them to exist in a primarily fossil fuel grid, supplementing them when the conditions are right. Make it so that using fossil fuels for even 20% or 10% of electricity generation is prohibitively expensive, and people will switch to nuclear power.

Last time I checked France was a democratic nation. So was Belgium. Both of those have achieve majority nuclear power generation, and France over 70%.

The cynical reality, though, is that you're right. People would rather make a token effort on intermittent sources, while continuing to burn fossil fuels for most of their energy. The damage to the environment caused by the continued use of fossil fuels in this approach, though, will eventually take a toll. But that toll will mostly be borne by poor people in the global south, not in the countries that had the capability to build nuclear but chose to primarily use fossil fuels supplement it with intermittent sources.

"Last time I checked France was a democratic nation. So was Belgium. Both of those have achieve majority nuclear power generation, and France over 70%."

That was the past. The dynamics have changed, and renewables are much more competitive now. Nobody is building more nuclear right now. True, there's paranoia, but there's also economics.

And I'm not talking about fossil fuels either.

Here's what I expect to happen today with a carbon tax: it'll kill fossil fuels, and give a huge boost to renewables. Nuclear won't benefit nearly as much, because renewables can sell each GW/h cheaper and are much faster and easier to build. We'll get a grid full of solar panels and wind, and probably serious instability. This is because the people that build powerplants don't care about the system as a whole, but about making profit within it.

At that point you can subsidize nuclear, heavily tax renewables, or subsidize storage. My view is that the last one is the long term solution because nuclear won't outcompete renewables long term.

> That was the past. The dynamics have changed, and renewables are much more competitive now. Nobody is building more nuclear right now.

Uh... https://en.wikipedia.org/wiki/Nuclear_power#/media/File:Nucl...

> Here's what I expect to happen today with a carbon tax: it'll kill fossil fuels, and give a huge boost to renewables. Nuclear won't benefit nearly as much, because renewables can sell each GW/h cheaper and are much faster and easier to build.

This is overly simplistic. Eliminating carbon emissions is not just about generating more clean energy. It's about replacing the energy that fossil fuels currently provide. It's hard to do that with intermittent sources.

> At that point you can subsidize nuclear, heavily tax renewables, or subsidize storage. My view is that the last one is the long term solution because nuclear won't outcompete renewables long term.

Perhaps, if we have a miraculous breakthrough in energy storage. But unless that happens, we'll end up building nuclear power to fulfill off-peak demand. And since nuclear power is just as cheap to run 100% of the time as it does to run part of the time it'll just make the bulk of renewables redundant.

If you have 100 GW of solar solar panels plus nuclear plants generating 100 GW for nighttime use, it's just as cheap to run the nuclear plants 24/7 and ditch the solar panels.

That map isn't particularly meaningful. Sure, stuff is being built technically. But as far as I know, the main places where it's being done for real are China and India.

The UK for instance has one powerplant actually in construction and it already got a bad rap because it's a bad deal economically.

Besides that, I think you're missing my point. My point is that you have to deal with reality, and reality doesn't really align with the way you want things to work. For instance, you said:

"So why not just build the nuclear plants and skip the renewables?"

My question is: "Who 'we'"? In a lot of countries, there's no "we" that applies. There's a government that sets the rules, and private enterprise that builds the plants. If "we" is the government, then they don't build powerplants themselves. They may allow them to be built, but a company still has to want to.

And if "we" is the commmercial enterprise, then nuclear is far too big for anybody to build it out of sheer altruism or good PR. That's big money territory and it must make a profit.

If you simply impose a carbon tax, private enterprise will just go and build solar. We have no storage? Those companies won't care. It's not their problem to solve. They'll build whatever makes the most money, which is almost definitely not nuclear.

If you want nuclear to happen you'll have to force it somehow, and I'm not seeing any particularly attractive ways of doing so. You want to be the politician who runs on a campaign of forbidding or heavily taxing solar and wind at the same time as dumping billions of $ into nuclear construction? Yeah, that'll go great, I'm sure.

> If you simply impose a carbon tax, private enterprise will just go and build solar.

Depends on how high the carbon tax is. Put it at a high enough rate that the country needs to go 100% carbon-free and people will build nuclear because that's the only solution (besides geographically limited things like geothermal and hydro) that can feasibly bring carbon emissions to zero.

Renewables are cheap when going from a mostly fossil fuel grid to a 50/50 renewable and fossil fuel grid. But bringing fossil fuels below 50% without the help of nuclear or hydroelectricity is extremely difficult. Any plan to do so basically assumes that some future breakthrough will make storage cost a fraction of what it does today.

> We have no storage? Those companies won't care. It's not their problem to solve.

Yeah, that's why there's no plan to actually decarbonize with renewables.

And if we actually want to stop climate change, yes it absolutely a problem that needs to be solved.

> If you want nuclear to happen you'll have to force it somehow, and I'm not seeing any particularly attractive ways of doing so. You want to be the politician who runs on a campaign of forbidding or heavily taxing solar and wind at the same time as dumping billions of $ into nuclear construction? Yeah, that'll go great, I'm sure.

Pass a carbon tax such that building a nuclear plant is less expensive than running solar during the day and natural gas at night. Renewables depend on fossil fuels until we make a breakthrough in storage.

One can look at Sweden and the green parties strategy for dealing with grid instability. Government are interested in a stable grid so they pay fossil fueled power plants to operate in backup mode. That way the power plant get paid twice, once by the government and then for any power that they manage to sell.

The second part to the plan is to spend a lot of tax money expanding the power lines to nearby country in order to increase the capacity for importing energy from nearby countries coal based power plants.

As a conclusion I agree that the people that build power plants don't care about the system as a whole. The government however do care about stability and mine is perfectly fine with spending tax money on that. Politically, voters are not going to be upset that money is spent on grid stability, even if then ends up in the hands of owners of fossil fueled power plants.