Comment by graeme

Comment by graeme 7 hours ago

18 replies

>We know how to build nuclear, we don't do it because its too expensive.

Refusing to build nuclear for decades makes it more expensive. If we start actually building reactors the cost will come down.

>the current Storage + Renewable pricing is so crazy good, that whatever you do with nuclear will just not be able to compete.

I would find this more persuasive if there were no new investment in carbon sources, but carbon sources have clearly remained competitive with batteries + solar, and global carbon emissions remain at an all time high. There's demand for baseload energy.

legulere 6 hours ago

Building nuclear power stations includes a lot of labor-intensive hard to automate tasks like construction. Baumol's cost disease means it's getting even more expensive: rising general productivity leads to higher wages and higher costs in fields that cannot increase productivity as much as the general economic growth. That's why it's also still cheaper in countries with access to low-cost labor.

SMRs are a try to get out of it by building more but smaller reactors. The reality is however that nuclear has an issue with scaling down. Output goes down way faster than costs and most SMR designs have outputs far greater than what initially counted as an SMR.

Investment in renewable energy already greatly outpaces investment in fossil energy. The economic decision to keep using a fossil system is a different one than having to choose a new one. There's still problems that have no economically competitive renewable solution yet, but a lot of what you are seeing is inertia.

Base load electricity is simply an economic optimisation: demand is not flat, but the cheapest electricity source might only be able to create a relatively flat output. You'll need more flexible plants to cover everything above the base load. If you have cheap gas, base load does not make any sense economically.

dalyons 6 hours ago

For the last two years more than 90% of new power generation capacity added globally was renewable. Est 95% in 2025. So no, new carbon sources are not competitive.

https://www.wri.org/insights/state-clean-energy-charted

  • graeme 6 hours ago

    Highly misleading stat. That's referring to capacity expansion, not new construction.

    Prior energy assets go offline and are replaced each year. The report you cite is discounting all of that, looking only at expansion above the baseline, then taking total renewable construction and calcuating renewable total construction's share of expansion. Apples to oranges.

    If you look at the chart in your own link you'll see that carbon construction investment exceeds renewables still.

    Chart: "Annual energy investment by selected country and region, 2015 and 2025"

    I would love for what you say to be true but it just isn't, even by that agency's own stats.

    • cycomanic 2 hours ago

      Not sure I understand your point. In the plot you mention what the OP said certainly holds true for China and Europe (less so for the US). Also the Charts plot investments not just new capacity investments, I'm not even sure how you distinguish between the two?

      • graeme 30 minutes ago

        The OP said new carbon sources are not competitive.

        ANY investment is by definition creating capacity that would not be there without the investment. If carbon were not competitive it would not get investment.

        If you sum up all of the carbon and compare to renewables in the chart there's more new carbon investment annually globally than renewables. (Comparing the dark lines vs the green line)

        Also this is ignoring "low emission fuels", which are still carbon sources, natural gas and the like.

        If you check the chart "Global electricity generation of zero-carbon sources vs. fossil fuels, 2000-2024" you can see that carbon sources were at an all time high in 2024. Growing slower is still growing.

        We ought to be shrinking these to zero. I'm very glad to see solar and wind growing but my point is nuclear is worth supporting as an non-carbon energy source that could replace some of this carbon load because of its baseload characteristics.

_aavaa_ 3 hours ago

> but carbon sources have clearly remained competitive with batteries + solar

That's because carbon sources are almost never made to pay for their externalities (i.e. pollution during energy generation).

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croes 7 hours ago

Nuclear is expensive even after the reactor is build.

And I wouldn’t call it progress to still rely on steam machines for energy

  • graeme 6 hours ago

    What's wrong with steam?

    It's better than carbon. And solar + battery requires more carbon to produce than nuclear energy as there's a lot of mining and physical construction involved + you must overbuild to supply power or rely on non solar sources.

    All for building solar. Do not understand the constant need to denigrate nuclear in favour of carbon sources while doing so.

    (If carbon sources were at zero this would be a different conversation)

    • epistasis 4 hours ago

      Nothing inherently wrong with steam, just as there's nothing inherently wrong with spinning rust hard disks or punch cards.

      We are at the end of the tech curve for steam, we have pushed it hard and made some super impressive technology, but it's not advancing anymore. Supercritical CO2 might have some advantages, or other fluids.

      We have zero-carbon tech that uses non-steam principles, and is currently on a tech curve that's getting cheaper than any thermodynamic cycle. We have storage tech now which is an even bigger revolution for the grid than cheap solar, because a huge limitation of the grid has always been the inability to store and buffer energy.

      I still have pinning rust disks, but only because they are cheap. If SSDs were cheaper, then we would see a massive switch.

      (BTW denigrating steam also denigrates all fossil fuel electricity sources, because they use the same mechanism, except for some natural gas turbines)

      • fc417fc802 4 minutes ago

        What is this, the hipster approach to technology evaluation? Steam conversion efficiency doesn't make sense as a metric for nuclear because (AFAIK) fuel consumption per watt isn't the primary driver of cost for that technology. Or am I mistaken?

        > I still have pinning rust disks, but only because they are cheap. If SSDs were cheaper, then we would see a massive switch.

        I only use this technology because it is more competitive than the alternatives for my usecase ... ?

        > denigrating steam also denigrates all fossil fuel electricity sources

        I doubt name calling is a sensible basis for policy decisions.

    • croes 6 hours ago

      It’s an inefficient way of producing energy. Only 30-35% results in electricity

  • ethmarks 7 hours ago

    > Nuclear is expensive even after the reactor is build.

    Solar panels and wind turbines need maintenance too. And they have much shorter operational lives than nuclear power plants, meaning they'll need to be expensively replaced much more frequently.

    > And I wouldn’t call it progress to still rely on steam machines for energy

    Could you please explain your objection to steam-based power? Is it purely aesthetic, or is there some inherent downside to steam turbines that I'm not aware of? Also, concentrated solar power systems that concentrate sunlight and use it to boil steam[1] are significantly more efficient than direct photovoltaics.

    [1]: https://en.wikipedia.org/wiki/Concentrated_solar_power

dzhiurgis 7 hours ago

> If we start actually building reactors the cost will come down.

Why would I invest then if it can't even pay for itself?