[Traubenfuchs]

I am still quite confused on the scientific consensus:

Should we double down on renewable energy and solve its issues with lots of batteries or should we invest in next generation nuclear energy?

Both at the same time?

Does anyone know?

[datakan]

Both at the same time. I don't see how putting all our eggs in a single basket benefits us.

[Tade0]

China does: all of the above, where it makes sense.

Renewables and batteries to keep your AC, workplace EV charger, stove, pool heater and (since recently) green ammonia producer going, nuclear to prevent e.g. aluminium smelters from seizing up.

Also the cheapest way to make renewables work 24/7 is to build HVDC lines - they cost as much as a highway per unit length and even undersea cables would deploy for less and faster than equivalent nuclear.

The total length of HVDC lines just in China is currently more than 40k km, so they've literally deployed enough of them to wrap around the globe.

[api]

China is also still building coal and has passed Europe and will (if they don’t change course) soon pass the US and Canada and the other big ones on a per capita emitter basis. They already passed everyone as top emitter in an absolute sense.

https://ourworldindata.org/grapher/co-emissions-per-capita

Not saying they’re not also building renewables and nuclear, but it seems like the policy is more “build anything and everything to satisfy demand” than a focused effort.

BTW: if you look at US emissions, the data center bubble hasn’t had much if any effect. They are still trending down. There’s reasons to dislike that industry but I’m sick of the mindless echo chamber doom on that issue. They’re not that significant in the grand scheme of things.

[atwrk]

Coal is already shrinking in the China (in absolute terms, not just as share of production) [1], and share of wind + solar is already larger than in the US [2], so I doubt China will ever reach US proportions in CO2 emissions per capita.

An additional data point to support that is that emissions intensity per GDP is clearly falling fast for China [3].

[1] https://ember-energy.org/data/electricity-data-explorer/?ent...

[2] https://ember-energy.org/data/electricity-data-explorer/?ent...

[3] Chart 75 from here: https://robbieandrew.github.io/GCB2025/

[Tade0]

According to this graph and assuming both US emissions fall and Chinese grow exponentially at the rate they were over the decade 2014-2024, the figures will cross around 2037.

Personally I doubt that, as US emissions have been going up due to data centers:

https://www.reuters.com/business/energy/us-leads-global-co2-...

And while China, like you said, doesn't seem to have a focused goal, it so happens that renewables are the path of least resistance for just having more energy as fast and cheap as possible.

[LargoLasskhyfv]

> They already passed everyone as top emitter in an absolute sense.

They also passed everyone as top emitter of produced goods, which almost everyone else has outsourced to there. So what?

Buy less? Buy American? European? More expensive? Reshore?

[preisschild]

Government should tax / provide incentives based on negative externalities such as environmental impact and let the free market decide

https://unece.org/sites/default/files/2022-04/LCA_3_FINAL%20...

I think a low carbon mix will result in the cheapest, most reliable and cleanest energy grid.

[sehansen]

If your location already has a well-run nuclear energy sector (Finland, Sweden, South Korea): invest in nuclear energy.

If you don't: stick to renewables.

And it also depends on what you mean by "we". As a Dane, I don't think us Danish taxpayers should invest in nuclear energy, but I'm perfectly happy that private Danish investors invest in Seaborg/Saltfoss and Copenhagen Atomics.

[bevekspldnw]

When it comes to avoiding the worst impacts of the current catastrophic path we’re on, “nothing will work, but everything might”.

Do it all.

[pfdietz]

Nuclear is not on a trajectory to do more than supply a minor amount of world energy. A (say) 10% nuclear, 90% renewable world is not an easier challenge than a 100% renewable world -- the intermittency/seasonality issues aren't eased by having 10% nuclear running as baseload, and keeping it as backup makes its cost per kWh explode.

Nuclear really has to go big (supply most of the world's energy) or go home. But supplying most of the world's energy means burner reactors are inadequate -- there isn't enough cheap uranium. Burner microreactors have even worse neutron economy, so this argument applies even more so to them.

[fssys]

nuclear takes longer to come online though vs renewables can be very quick, so it makes sense to do both as a short-long term strategy

[pfdietz]

As the renewables quickly come online, they push down their experience curves and get cheaper, and the residual demand is increasingly intermittent. Both these considerations mean the economic environment will get worse for nuclear over time. I think this is why there's a rather frantic online push for nuclear: it's now or never for the nuclear bros.

[tech_ken]

It's more of an engineering call than something that can be purely determined from inductive reasoning. I think most engineers working in the space would say "both" are needed, but partisans exist on both sides.

[rayiner]

That's a political and economic question, not a scientific one. Science can provide input information, but the decision involves weighing all sorts of facts and considerations outside the scope of science.

[mohamedkoubaa]

Exactly. Waiting for a scientific consensus on a question that is very clearly not posed as a scientific question is oddly cultish

[nsonha]

We're gonna need portable energy storage regardless of energy source, it's battery vs fuel. There is no such things as battery vs atomic core.

[pfdietz]

Nuclear partisans like to call renewables ideological, but I think this is another example of "the accusation is a confession".

The empirical evidence has nuclear being uncompetitively expensive. The current focus on variant reactor designs appears to be something of a Hail Mary attempt to get around this sad state of affairs.

You sometimes see them making an argument about energy density, which goes back to Vaclav Smil. But Smil used this argument to massively mispredict how solar would be go in the market. We don't hear him much anymore.

Nuclear advocates increasingly resort to conspiracy theoretic reasoning to explain away the failure of their technology to compete. This should be a red flag.

[rayiner]

> The empirical evidence has nuclear being uncompetitively expensive.

France nuclearized 75% of its grid in the 1980s while the solar folks were faffing around. It's not a cost issue, it's that anti-nuclear folks have choked out the industry.

We need to take the boot off the neck of nuclear. Wind and solar aren't an avenue to moving up the tech tree of civilization, which will involve using vastly more power.

[pfdietz]

We don't actually know how much that cost France, sine it was mixed in with their military nuclear effort. French auditors threw up their hands trying to figure out the actual costs.

What we do know is their attempt to build more NPPs now has gone spectacularly tits up, with costs completely out of control. This should make one view their earlier efforts with great suspicion. Have they become much worse, or were earlier problems concealed?

[rayiner]

Costs are out of control due to nuclear regulation.

[pfdietz]

This is the conspiracy theory reasoning I was talking about. Nuclear is wonderful, but a global omnipotent green conspiracy has hobbled it.

Or, maybe, it really is complicated and needs regulation to keep it sufficiently safe in a world where corners are always cut.

[ToValueFunfetti]

Right or wrong, I don't think conspiratorial is the right descriptor here. The pro-nuclear claim is that the very loud, very public anti-nuclear movement was influential in setting regulations of the industry. It's not "an evil cabal of shadowy green elites secretly control everything", it's "democracy works; fellow citizens were/are dumb; legislation improvements move slowly".

[tech_ken]

> moving up the tech tree of civilization

Life isn't Civ 6, there is no tech tree to climb.

[rayiner]

Incorrect. Compare Bangladesh to the United States.

[tech_ken]

Tech development != tech tree, history is nonlinear and ecological. Linear, unlockable "tech trees" are an ahistorical fantasy necessary to make some video games fun and digestible. Applying them to the real world is like trying to win a war by replicating the Battle of Helm's Deep or something.

[rayiner]

I’m not saying it’s literally a tree. My point is that we need vastly more power to upgrade to the next level of civilization.

[rs_rs_rs_rs_rs]

>The empirical evidence has nuclear being uncompetitively expensive

I have a solution, take the subsidies spent on "renewables" and put them into nuclear! Easy peasy!

[bryanlarsen]

Too late, governments have already subsidized nuclear more than they've subsidized renewables.

[pfdietz]

Renewables have shown excellent experience effects. These effects are a kind of positive externality: improvements in the technology become available generally to future consumers. It makes sense to subsidize positive externalities, just as it makes sense to penalize negative ones.

If nuclear had shown good experience effects it too would have merited its subsidies. Unfortunately it hasn't done that.

[krunck]

next generation nuclear energy = fusion

[pfdietz]

Fusion's main accomplishment will likely be to make fission look cheap in comparison, due to fundamental issues of power density in the nuclear island. Why make a huge complex low power density radioactive thing when you can make a much smaller simpler high power density radioactive thing?

[api]

Both.

We should be investing in all non carbon emitting sources and we should have been doing it since the 1970s when we figured out pretty conclusively that this would be a problem.

Instead we had right wing fossil fuel shills on one shoulder and unscientific woo woo greens on the other, the net effect being that we kept burning more carbon. We still have them, Trump with “beautiful coal” and greens now opposing even solar power and batteries, but climate change is no longer possible to ignore. Some still manage it but those people are nuts.

If we hadn’t stopped improving nuclear we’d probably have emitted half the CO2 we have. It would have become cheaper and safer and more scalable and then when China industrialized they would have copied that instead of burning so much coal.

France with its nearly zero carbon grid is the existence proof.

It wasn’t until the 2010s that solar and wind became grid scale in a big enough way to matter. That was too slow.

Whether someone is at least open to nuclear power is my litmus test for whether they take climate change seriously.

I do. If we hit 600, 800, 1000 ppm CO2, which is possible if the world keeps developing on the back of fossil fuels, we are entering existential risk territory. Earth has had those CO2 levels before, and higher, but our species was not alive then.

We already passed the FAFO threshold for ppm CO2 and now we will FO. But that’s not X-risk yet. I’m talking about the next threshold, which may start around 600 but really kicks in near 1000. This is where you actually start asphyxiating. You get lowered IQ and impaired judgement to a small degree, but across the globe at a time when we really don’t need it.