> How do you propose to use much less energy without starving everyone?

That's the whole point: degrowth is about re-organizing society such that we don't starve. There are big efforts of planning for that in many places. Look at the "shift project" in France. It seems to me that the US are very, very, very far behind on that matter. The US seems to still be stuck on the Silicon Valley mindset ("they will save us with new technology"). But that's not representative of the rest of the world.

> Where does the energy come from if not fossil fuels without conscripting people to be peasants? Does it matter if mass death is caused famine or "degrowth"?

The idea of degrowth is that in order to avoid famines, we have to drastically reduce other stuff and reorganize society. Planes are not even a question there: planes will go away, because everyone agrees that we'd rather eat that fly. There are many decisions that are harder to make, though.

Those who don't believe in degrowth and instead think that "there will be a miracle technology that will save us" are just naive. Degrowth advocates are the ones who are actually trying to play with the cards they were dealt.

The first problem is no details like how much needs to be cut. You suggested it is impossible to build enough solar. Do we have to shrink to 10% (renewable electricity) or 20% (plus nuclear)?

A good example or problem with degrowth is proclamation that things like planes won’t be possible. Aviation is 2% of emissions. There are lots of little things that they add up. Like concrete being 3%, but nobody says that have to give up concrete. The big ones are things like heating and cooling and transportation that are hard to give up.

The other problem is that we mostly know how to solve aviation. Hydrogen or liquid fuels should work, both produced from green energy. New technology but no miracles. We know how to do green electricity.

I agree with you that we need to change the world a lot. But it won’t work if impose suffering on people. Or do things that don’t work or don’t help.

> A good example or problem with degrowth is proclamation that things like planes won’t be possible. Aviation is 2% of emissions.

Aviation came with oil, it will disappear with oil. It's not a problem of emissions per se, it's a problem of energy. Fossil fuels are not unlimited and we don't know how to completely replace them.

> The big ones are things like heating and cooling

We need to work hard on building isolation, obviously. And people need to live in smaller habitations.

> and transportation

We need more trains

> Hydrogen or liquid fuels should work, both produced from green energy.

Same thing: if you look at the numbers, we won't have enough green energy to produce enough hydrogen for aviation, even if technically we can make planes fly with hydrogen. We will have to choose where we use our hydrogen: for planes, or for steel and agriculture?

> But it won’t work if impose suffering on people.

Yep, we need to teach people and hope they accept to do what's needed to survive.

> Or do things that don’t work or don’t help.

Totally agreed here. Hoping for anything short of degrowth doesn't help. We need everything PLUS degrowth. And still, it will be hard because climate is already pretty messed up (with inertia) and biodiversity is looking bad.

We will have inexhaustible amounts of green energy and green hydrogen. Degrowthers are just a variant of doomers. They believe they already know the future and it is a grim one. It is both hyper-pessimistic while also being hyper-arrogant.

And thinking that we will have inexhaustible amounts of green energy is not hyper-optimistic and hyper-arrogant?

We don't currently have inexhaustible amounts of green energy, and we don't have any viable solution right now. If you think that because we can make 1 solar panel, we will be able to replace fossil fuels, then you have obviously never done any kind of engineering in your life. Problems come with scale. It's not being hyper-pessimistic to know that.

It's immediately obvious from basic physics that the world is bathed in green energy. It's availability is thousands of times greater than fossil fuel energy: https://www.freeingenergy.com/the-earth-gets-more-solar-ener...

The problem with doomers and degrowthers is that they are pretty ignorant people. They just assume that there's no solution or that green energy is just too weak to solve problems. This is why they are arrogant and not just pessimistic. They believe they already know the answer despite never looking for possible answers in the first place.

I said you have no clue about engineering, not about basic physics. There is a big difference between saying "but Proxima Centauri is a nuclear fusion reactor producing a ton of energy" and actually leveraging it.

Last I checked, solar power is very cheap. Your problem is the same as with many degrowthers, you are basically stuck in the past and refuse to change your mind despite new information. It is the arrogance of "knowing everything" while not having any desire to learn.

You completely miss my point. You are the arrogant want saying "don't worry, we can solve it, we know". I am the one with humility saying "guys, I have seen how engineering works, it's always harder than we think". Tell me: how do you make plastic with solar energy? Because last time I checked, plastic was made of oil. There are tons of engineering problems (from the fact that nobody has ever produced that much solar energy to the fact that you can't control solar energy - what do you do when there is no sun? Happens at least every night...).

Plus, if your only reference is the price of solar power today, then you are highly uninformed on the subject at hand. Of course solar power is cheap: in many places it is subsidized, and it is built with cheap, abundant fossil fuels. But make no mistake: solar today is absolutely marginal. So you are extrapolating from the current marginal energy production of solar to 100% of the world, with the only argument that "last you checked, solar today is very cheap" and "those who believe they know slightly more than me are arrogant, I won't listen to them".

> while not having any desire to learn.

Let me take you on that. I will share with you my favorite introduction book on the subject (it is cheap, from a really respected french engineer, and it took me 5h to read). If you do have any desire to learn, read it seriously. Now in all fairness, if you share with me the title of a serious book that explains why degrowth is "arrogant and stupid", I commit to reading it.

Do we have a deal?

My choice is "World without end" (in French: "Le monde sans fin"):

https://www.amazon.com/World-Without-End-Blain-Christophe-eb...

If you can make hydrogen and capture carbon, you have the ingredients for making plastics. It will likely be more expensive than today’s plastics, at least initially, but for critical needs like medical devices, this is totally acceptable.

You can build solar and wind power without fossil fuels, or at least not much. We are able to power large vehicles and industry with renewable energy now. Most notably, with the advent of green steel, infrastructure projects in general no longer require significant use of fossil fuels. Now to be fair, this was not known to the greenies, who thought that solar panels on the roof and an EV in the garage will magical solve everything. But it is known to those who actually study this problem. This problem is rapidly resolving itself in reality.

I cannot read a book in a short amount of time. But from the sample it is just repeating fairly simplistic arguments against green energy. It is mostly a repeat of what was being said on theoildrum.com from a while back. Even then, they were mostly wrong. These days, the few areas where they were right are also being proven wrong. It is akin to the “god of the gaps” argument, where the gaps where we didn’t know how to eliminate fossil fuel usage are constantly shrinking.