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Comment by JohnFen | Hacker News Reader

"Ever" is a very long time.

Will we get fusion power in the next few decades? I wouldn't bet on it, but I also wouldn't bet against it.

At this point I would bet against commercial fusion power plants. It was always questionable if they would be cost competitive with fission power plants, but now even those are being replaced by renewables and grid storage.

The bigger problem is that fusion plants aren't useful for making weapons. Fission plants were basically a side project of the nuclear arms race, which is why they're a dying industry now. The world already has all of the nuclear bombs it will ever need and despite all of the promises they never managed to compete on cost. It's so much easier and cheaper to install wind turbines, solar panels, and grid scale batteries that there will probably never be a market for a commercial fusion power plant.

There's a huge surge of investment into Nuclear these last few years. Innovation is starting again in that sector, I wouldn't bet against it.

Investment in renewables dwarfs that in nuclear now. Hell, it's exceeding investment in fossil fuels.

So replacing old infrastructure is now an investment? There are just many reactors EoL and I'd say replacing those is not a sign that nuclear is booming right now.

The future is wind/solar/battery on cost alone.

> So replacing old infrastructure is now an investment?

Yes? What did you think it was, chopped liver?

Strong Wind doesn't exist on asteroids and many planets, so I think there will be a long term need. Solar power decreases with the cube root of distance from the sun,so twice the distance is 1/8th the flux

I'm not concerned about commercially viable space colonies in my lifetime.

The real reason for fusion was that fission is not a renewable resource. In a few thousand years there will be a fuel problem with fission and we would be forced to switch to fusion if we had a fully nuclear power system.

Who said anything about concern? Im not in charge of making global decisions about fusion research, and I doubt you are either.

That leaves low stakes idle speculation.

I'm entirely content on relying on sci-fi energy production for a few thousand years from now.

This might sound like the same attitude that put us in our present climate crisis, but that was on the order of decades to centuries. Thousands of years include such unbelievable potential of technological development that there seems no point in trying to predict the actual challenges we'll face.

Interestingly enough, some of the advancements in fusion research and lasers may help with fission waste fuel recycling. [1] Though breeder reactors might end up being more economical.

https://nap.nationalacademies.org/read/4912/chapter/20

Nitpick: Radiation decreases with the square of the distance (twice the distance, 1/4 the energy). This is because the surface of a sphere (which is where energy is collected) is 2D, not 3D.

I stand corrected

We'll let the space colonists worry about that. It provides no justification for anyone I know to pay for it.

Solar decreases as 1/r^2. Cube root? Where did that come from?

I would bet against it. We haven't even built one of the key facilities to test the materials that we would hope to make a fusion reactor from. Once built, it will still take 20 years or so (as I recall) to come to some conclusions about suitable materials.

The sun is able to use gravity containment. Terrestrial fusion has to use magnetic and physical containment. The extremely high energy neutrons produced rapidly deteriorate common engineering materials. A replacement schedule is very difficult because of induced radioactivity, which means that the reactor cladding would need to be replaced by robots most likely.

https://en.wikipedia.org/wiki/International_Fusion_Materials...

Given how rapidly the price of batteries and solar are falling, it seems absurd to think it will make any economic sense to spend tens of billions of dollars on a monster fusion plant.

China are churning out regular old fission plants, and have 27 under construction right now. Even still, the average build time is 7 years.

So even if we get some breakthrough and figure out how to build a commercial fusion plant, it's a certainty it won't be up and running for something like 10-15 years. Solar and batteries will be so cheap there won't be any discussions.

> Given how rapidly the price of batteries and solar are falling

Battery prices are pretty stable, which is huge problem for wind and solar energy.

That's just so bizarrely wrong I don't even know where it came from.

The price of batteries has declined by 97% in the last three decades: https://ourworldindata.org/battery-price-decline

This article is outdated. The price has been relatively stable in the last ~4 years: https://assets.bbhub.io/professional/sites/24/fig1battery.pn...

Prices are decreasing much slower now. At this pace, large scale energy storage for replacing stable energy sources like coal and fission power plants is far out of reach.

> The price has been relatively stable in the last ~4 years

Your linked source shows the price in the last 4 years going from

cell: $128->$107

Pack: $55->$32

Real: $183->$139

So the price has dropped 25% in the last 4 years. That is NOT relatively stable by any definition.

If you look at the beginning of the chart, the price decrease (from $780 to $258 in 2017) over the same four year period was 67%. And for 2023 it was only 24%. So progress has slowed a lot. In 2022 there was even a year-over-year price increase. That's bad news when you want to build massive energy storage systems that can replace power plants.

So what you're trying to say is - "In the past prices fell extremely fast, now they're falling just regular fast".

I'm saying that prices are falling increasingly more slowly and that using solar+batteries to replace coal, gas and fission power plants will probably not happen.

> using solar+batteries to replace coal, gas and fission power plants will probably not happen

That ship already sailed, many countries are already doing it.

No, no country is doing it because batteries are far too expensive to replace stable energy sources.

The UK has been burning coal since 1882, and their last coal fired power plant just got it's last delivery of coal [1]

Germany is shutting down it's nukes [2]

Actually, lots of countries are very quickly increasing how much of their energy needs come from green sources [3]

You can't deny reality

[1] https://www.bbc.com/news/articles/ckkg0wl7dkro

[2] https://www.base.bund.de/EN/ns/nuclear-phase-out/nuclear-pha...

[3] https://www.climatecouncil.org.au/11-countries-leading-the-c...

Solar and wind energy are impossible without stable energy sources like coal or fission. Solar and wind energy are highly volatile, and battery energy storage is far too expensive.

You already said that, and you're ignoring the fact that many countries are switching from coal and nuclear to renewables, thanks in part to the rapidly falling prices.

just today, the UK had its last coal delivery to a power plant. after that, it's closing and the UK will no longer be using coal at all.

https://www.bbc.com/news/articles/ckkg0wl7dkro

This is irrelevant to what we were discussing originally. Neither the UK nor any other country does have battery storage of the size of major power plants. Those are required to provide stable energy. Otherwise the power would go out during calm or in the night.

As I've shown, many countries are making the change.

It will take some time, you can't build this level of infrastructure overnight.

Here's another from today: https://driveteslacanada.ca/news/contact-energy-picks-tesla-...

You haven't shown that "many countries" are building large-scale battery grid storage.

Last quarter Tesla deployed 4GWh of battery capacity, this quarter it is 9.4GWh.

Where do you think that is being deployed?

Yeah, where is it deployed? To balance out the volatility of solar and wind energy?

yes, exactly.

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