Hacker News Reader

Comment by tanbog | Hacker News Reader

I don't begrudge money being spent on researching fusion. It is definitely a promising technology, but it's not coming to a power grid near you any time soon.

Even if we can figure out how to keep a reaction going with a useful energy surplus no one has any idea

a) How much a reactor will cost,

b) how long/hard will it be to build or

c) If there are any issues with the process - yes no nuclear fuel but there's still some nasty crap coming out of the reaction which you will have to deal with if you scale the technology.

Meanwhile there are a number of perfectly viable planet saving power sources - solar, wind, solar-thermal etc - already out there providing power.

Fusion is a nice idea, but it isn't the only way to save the world...

View on HN

I too like the idea of Fusion reactors, (I am enamored with the dreamy prospect of fusion for space travel), but I think Elon Musk's observation is obligatory here:

Why spend huge sums in a fusion reactor, when we have a perfectly reliable funsion reactor right above us, the Sun, giving power at a convenient form (~500nm light -- far better than heat), at convenient power densities (not too high to overheat panels and not too low to be uneconomical), is available virtually everywhere, etc. It really is like we had already built a reactor and only need to add the last, least expensive, bit of energy harvesting.

The only thing Solar cannot compete well with are fossil fuels, which are essentially like discovering charged batteries buried in the ground (which is great, but they'll run out, and are ruining our environment), or wind/hydro in some places (where energy is begging to be harvested in the form of kinetic energy or potential).

Our salvation (for this crisis :) ) is indeed already within our reach, we only need to act...

Yep, our global fusion plant in the sky.

The why is essentially density and availability. While solar is great for cheapness it has other constraints. It may still be more expensive in kWHr cost but it would certainly have its uses.

> The only thing Solar cannot compete well with are fossil fuels

So, that's sort of the point of fusion. It's clean energy with no need for storage.

One way of harvesting solar energy that's technically possible but is not even on the horizon, as far as I know, is using giant mirrors or lenses out in space to focus sunlight down to Earth.

If it weren't for its potential use as a weapon, I'd look forward to seeing it put in practice.

"it's not coming to a power grid near you any time soon"

"soon" is relative. The older I get, the more something a century or even two away doesn't seem that far off, and something that could arrive in 20 years seems positively near.

The Long Now project strives to get people to think more long-term, and I've heard that in some parts of Asia governments and organizations plan on far longer time horizons than is common in the West.

The world would be far better off if more of us adopted such a perspective, rather than focusing on only on what can be done now or in the next few years.

I totally agree with your sentiment in general. However, when you wake up in the middle of the night and realise your house is on fire, you don't have time to ponder the future fire prevention technologies. You need to get out of bed and start putting the fire out. "House on fire" is where we are now in regards to climate change.

No we aren't at "House on fire" state yet. Once people start dying en masse and wars are breaking out over liveable land and resources is when we have reached "House on fire" territory.

We are currently at we know we have an electrical problem in the walls that we know will cause a house fire in the future if we don't fix it.

Attibuting any specific catastrophic event to climate change is hardly possible, though. Arguably, climate change is already playing a role in conflicts around the world. The arab spring (and therefore the ongoing war in Syria) was partly triggered by discontent over food prices, which are of course closely linked to the local weather and thus climate change. Here's an article that explores this is some more detail:

https://www.globalcitizen.org/en/content/conflicts-affected-...

That is a localized conflict. It really is a problem once the entire world is touched. If global warming will not result in large scale wars and people dying en masse it's not really a problem. It would mean global warning would only entail a reduction in quality of life not large enough to warrant violence.

Even if global warning has a death toll of 10% of the world population I don't consider that a real problem. As long as humanity can progress afterwards it's fine.

>Even if global warning has a death toll of 10% of the world population I don't consider that a real problem.

Absolutely incredible. Are you picturing your friends and family in this hypothetical 10% death toll? Or the social conditions that would result in this number (comparable to Germany in WW2)?

What is so horrifying to you about stopping global warming, that literally decimating the world's population is the less bad option?

I never said it wouldn't be horrible. But let's be honest the human species lived on after WW2. I'm not sure where you got that I think that stopping global warming is horrifying, I don't think I ever said that. Beside that point that is not what I believe.

I think it would be great if we could stop global warming. But I don't think it socially possible. The only glimmer of hope I have left is that it is only a significant reduction of the human population while the rest can move on.

> We are currently at we know we have an electrical problem in the walls that we know will cause a house fire in the future if we don't fix it.

I disagree. Permanent damage has already been dealt. To continue with the house analogy, we can probably still save a smaller or bigger part of it depending on how quick we are to put the fire down.

But irreversible damage has already been done: even if we were to stop our carbon emissions right away, sea levels would still rise quite a bit (more than 1m by 2100-2300 IIRC). Every species that goes extinct will stay extinct, forever. And many are headed down this path. Biodiversity has suffered a lot in many places.

Think about this: we can complain about having to deal with radioactive garbage in 100ky, but any species that disappears today will not come back, even after billions of years. And millions of would-be species from its possible ofspring won't ever be either.

Those thoughts put things in perspective. I find them daunting, and this has led a lot of people to take the "climate emergency" very seriously. Our house is already on fire. Even if we start putting it out, we know it will still continue growing at least for a bit after we start pumping water, but we'd better start ASAP.

No, mass death and wars would be "you are currently dying in the fire". There is a fire, it has already destroyed many things, but it hasn't yet reached the sofa, where we are currently sitting complacently.

"You are currently dying in the fire" Would be humanity is extinct. Mass death and wars don't mean humanity is doomed.

No, extinction would be "you have died in the fire". "Mass deaths" is what the process of going extinct looks like.

I'm not sure where you are from but in my reality you don't really bounce back when you are dying in fire.

Not everyone needs to be a firefighter.

Longer term vision is still required.

Hell, there are hundreds of thousands, if not millions of trained physicists, chemists, material scientists, etc, who aren't even engaged in relevant work at all - they fall into neither camp.

This is the best argument for extensive research into life-span extension.

One of the megatrends of the last 200 years has been a huge increase in the time horizon deemed acceptable for investment payoff.

Generally, humans aren't willing to forgo things today for a payoff more than about half a life-span away. Today, a true long-term investor considers the 30-year return on their investment.

An investment that won't make a return for 50 years or more mostly isn't worth making.

But, if you knew you would still be healthy enough to enjoy the profits in 90 or 100 years, you might be willing to invest for the even-longer term (historical trends suggest this to be true)

Government grants are fun and all, but the way you get thing going big is to get them funded by people who are hoping to profit, not just hoping to make the world better in some way

I have also been thinking about this lately.

Imagine for a moment that cryogenization technology became available tomorrow. Would that help? Should we start forcing everyone to spend 3 years in cryo sleep every year, thus extending everyone's lifespan 400%?

This is far-fetched and just sci-fi for now, but interesting to think about nevertheless: should you go into cryo sleep while you are waiting for the right job offer? Should we cryogenize refugees while we are waiting to find them some shelter after a disaster or a war happens? People surely take a lot less resources if you can stack them, and they are not moving, feeding, etc.

Something like this would require us rethinking our ethics and society, yet it would be a very welcome way to start thinking more about the future.

If you would like to read some sci-fi that plays with the idea of skipping through life via cryosleep, try The Worthing Saga by Orson Scott Card.

It's one of his earliest works, so it isn't as well-produced as some of his later stuff, but it explores some very interesting ideas.

(This story began life as a different novel called Hot Sleep. Having read both, I honestly can't remember which parts are in which version, but Card himself says he considers The Worthing Saga to be the official version)

(hint: in Card's story, cryotech created a dystopian, not utopian society)

Card is a Mormon. Not surprised that his fiction is dystopian.

Not all his fiction is dystopian.

Considering the suicide rate, if such technology was available, you'd probably get a lot of takers.

This comment could be posted on every article about fusion until there is a new fusion power plant opening day announcement.

Do you think it's worthwhile to discourage humanity from attempting new things because there are existing sub optimal alternatives?

Or are you just trying to sound contrarian for internet points?

(Despite what you're saying being the safest, most boring, done to death, remarks on fusion)

'but it's not coming to a power grid near you any time soon' - there's about 5 companies aiming for ~2030 commercial fusion; so not terribly long - ok, most of them wont get there, but maybe if one does even a few years late? I think at least some of them have (a) & (b) in mind - (c) is probably harder.

Solar and wind covers 1% of worlds energy consumption it's expected to be around 3-4% in 2040.

https://www.iea.org/weo/?fbclid=IwAR2LwDYcozvpGCOa3bIi2ieMbj...

You left out d) how long will it last?

Fusion reactions produce lots of neutrons, and neutrons weaken metal, in many cases within a few hours.

It may be that a "successful" fusion reactor is still a failure because it can run for only a few hours, days, or weeks before it has to be scrapped and completely rebuilt.

I watched a presentation by the article's author, about MIT's ARC reactor design. He said they would replace the inner wall of the reactor once per year. In operation that would be surrounded by molten FLiBe salt, which would absorb the neutrons and breed tritium fuel. The inner wall would be 3D-printed, and the superconducting coils would be hinged so the reactor could easily open up; MIT has already tested joints in modern superconducting tape.

MIT spun off the company Commonwealth to commercialize the idea.

> Meanwhile there are a number of perfectly viable planet saving power sources - solar, wind, solar-thermal etc

And nuclear fission first, if you want to be realistic.

Also given the time frame that we need to decarbonize the grid, we can't really put our hopes in fusion for the near to medium term.

> nobody knows x about fusion

That's why research is needed otherwise researching will take the research duration plus the delay imposed by people saying it won't be here anytime soon anyway.

> perfectly viable power sources like solar, wind, solar-thermal etc.

Until humanity has figured viable massively scalable long term power storage solutions we will always be at the mercy of natural phenomena (time of day, wind speed and direction etc). Additionally AFAIK "renewable power sources" don't have the necessary power density to make them viable as humanity's exclusive power source.

> Until humanity has figured viable massively scalable long term power storage solutions we will always be at the mercy of natural phenomena (time of day, wind speed and direction etc).

I would argue we just need to make sure ongoing power needs are met - ie we can always turn the lights on. This doesn't need "scalable long term" storage - although pumped hydro, batteries, thermal salt all work well - it just needs sensible grid design so the needs at any one time are met by available power sources.

This above is obviously a "harder" problem than to just have a few big power plants you can throttle on or off but not that much harder and we already have the technology and knowledge - if not the political will - to do it.

> Additionally AFAIK "renewable power sources" don't have the necessary power density to make them viable as humanity's exclusive power source.

This is flat out wrong. many communities already exist exclusively on renewables.

> This is flat out wrong. many communities already exist exclusively on renewables.

"Communities" maybe but what about (heavy) industry like the the one required to e.g. manufacture more wind/water turbines and parts, (continue) to research more efficient technologies in the future, to sustain the growing population etc. ?

Iceland seems to do pretty well on almost exclusively renewables. And this includes Aluminium smelters which are amongst the most power-intensive heavy industries.

Iceland uses plenty of geothermal power. That doesn't say anything about what's feasible with wind/solar.

Wind/solar and hydro/geothermal really should be described by different words. Using "renewables" for both causes a lot of confusion.

Reply on news.ycombinator.com