[palata]

> The worst case is that you replace them with nuclear

Not remotely the worst case. How do you expect to power all the ships needed for globalisation with nuclear power? What about planes? Can a rocket take off with a nuclear engine?

Fossil fuels account for 80% of the energy we use, electricity merely 20%. A whole lot of those 80% come from use-cases that were built around fossil fuels (how do you make plastic and all the materials that depend on it with nuclear energy?), and we don't (yet) have a way to replace that with something else. Try to power a ship with electricity...

Hydrogen, you say? We would need a lot more energy to produce enough hydrogen to replace oil. So we're going from "we don't have a way to compensate for the lack of oil" with "our solution is to not only compensate, but actually produce more energy than what oil was giving us".

All that while currently living a mass extinction and having already missed the reasonable objectives for global warming. So we have a few decades to get there, and what we have seen in the last few decades is that all we have achieved is making the problem worse.

[zizee]

There are many nuclear powered ships. If the decision is between nuclear proliferation, or the end of the global economy, I'm betting we'll choose the former.

If you have enough electricity, you can manufacture avgas, methane and whatever other fuels you need for aerospace.

[palata]

> There are many nuclear powered ships

What's the ratio of nuclear-powered big ships vs non-nuclear-powered big ships?

> If you have enough electricity

We're talking about moving our current electricity production entirely out of fossil fuels (because we produce a lot of electricity with them), then multiplying that production by 5, and at this point we're only producing the same amount of energy as today. But of course that's not enough, because we then need to use a lot of that energy to produce what's needed to replace oil, e.g. hydrogen.

We currently need what... 10-15 years to build a nuclear power plant? We're talking about building multiple orders of magnitudes more of them in a few decades, together with the electrical network and of course everything that needs to be re-engineered now that they can't run with oil anymore. And we're currently using oil for a reason: it's super dense, there is nothing more convenient.

And what value does it add? Nothing. It's just for replacing what currently works. Who will pay for that? Where will the money come from?

And this has to be done in a context where geopolitical instability will grow every year (because it is a fact: our access to abundant fossil fuel is coming to an end; Europe has seen it since 2007). And of course in a context where we are not remotely thinking about doing it. In the last decades, we as a society have actually kept accelerating in the opposite direction.

How realistic do you think your scenario is, really?

[bluGill]

> We currently need what... 10-15 years to build a nuclear power plant

Part of this is we don't build a lot of them and so are not good at it. If we set out to build hundreds of them per year we could do that, and costs would go down.

>And what value does it add? Nothing. It's just for replacing what currently works. Who will pay for that? Where will the money come from?

That is not an issue. A quick search says that ships have a lifetime to 20-30 years after which they are replaced. Sure there are a few antiques older than that, but for the vast majority of ships the owner will pay to replace it in 20-30 years anyway. Oil is not going to run out on a single day, it will be a process of years which is plenty of time for normal processes to work.

I don't favor nuclear in general, but for large ships it remains the only thing I know of that makes sense. (synthetic fuels are expensive, and solar/wind needs more space than a ship to deliver the power a ship wants).

[palata]

> If we set out to build hundreds of them per year we could do that, and costs would go down.

How do you get from "it takes 10 years now" to "it takes less than a year now if we really want it"?

Also you need qualified people to build that, it's not like you can vibe code it.

Again, peak oil in Europe was 2007, in the world it was currently 2018, it's not like we have 100 years to solve our energy problem. And I'm not talking about climate yet.

[bluGill]

It will take a few years of investment to develop qualified people to build it. We can't do it overnight, but we can in a few years if that is made a goal.

>peak oil in Europe was 2007

Europe is still using a lot of oil in 2025! They didn't have to change overnight, it is a long term process.

[palata]

> but we can in a few years if that is made a goal.

But that is very far from being a goal! Every year we emit more CO2, even though we already start seeing the effects of climate change (it's only beginning), but we keep accelerating in the wrong direction.

> Europe is still using a lot of oil in 2025!

That's not what I said. First, Europe imports pretty much the totality of their fossil fuels. And second, the European economy has been slowing down since 2007. The US likes to say "we have a better economy because we work more and better", but actually it seems pretty reasonable to think that it may be related to access to fossil fuels.

[AlessandroF6587]

Some reference material that can be helpful https://www.tesla.com/blog/master-plan-part-3

[numpad0]

It doesn't take much time or effort to build nuclear powered anything if you were not concerned with bunch of turbojet Boeing planes circling above you. It takes centuries if you were.

[orbifold]

It is possibly to create synthetic fuel from coal. For usecases that absolutely require fuel we would be able to synthetically create it.

[palata]

It's not a question of what use-cases theoretically require fossil fuels. The whole problem is the scale.

We have to find a replacement for oil and get it to the scale of oil in a fraction of the time we had to get where we are now with oil. And getting there with oil was easier, because oil is extremely convenient.

It's a bit like saying "we need to rewrite the Linux kernel with a new language that we are yet to invent, and it has to reach feature-parity in 5 years". Sure, theoretically we know how to create a new language and how to write a kernel, but can we do both in 5 years? Ever heard of e.g. Fuchsia? And they didn't try to invent a language for it.

[bluGill]

The Germans were able to transition from oil to synthetic fuels while in the middle of WWII. South Africa used the same to provide their energy for decades when the world prevented them from getting oil. We know from those experiences that synthetic fuels scale.

We also know from experience that synthetic fuels are around 5 times more expensive than oil, and so only niches are willing to pay for it if oil is an alternative.

[mensetmanusman]

Yes. With enough energy you can make anything.

[palata]

Exactly. The problem is that we live in a finite world, we don't have infinite energy. And one of our biggest problems right now is energy (together with the current mass extinction and climate change).