Is it really a 'scientific breakthrough' if it's just that they've firing fusion shots with 'net positive energy output'?
Good work, but IMHO we're still a long way from using fusion for energy, if ever, even if only because it will be so expensive to build and run these ultra-high-tech plants. But also because of all the downsides of D-T fusion, like, where is the tritium, and that most of the energy comes of as fast neutrons, etc.
It saves time. The most you can actually get from such an announcement is to slightly update your priors. It doesn't affect your actions at all. So you see it, note it, become slightly miffed that the Internet will be full of comments that think it's a bigger deal than it is, and move on with your life.
The cynicism serves as a mental balance to the hype that might otherwise tempt you to spend more time on this than it merits.
When dealing with news, skepticism and cynicism are practically identical. They're not the same, but cynicism is less effort and achieves similar results.
And it's easily reversed. If this turns out to be useful, you'll get many more chances to re-evaluate.
For those who are looking for general info on nuclear fusion tech, the real engineering youtube recently put out a nice explainer video on how its done and what the various constraints are:
Yeah, but you can't since the energy produced is in form of heat and radiation and not electricity.
That is like using lasers to start a fire and then saying: Look the fire is producing energy in the form of heat! But the heat has to be turned to electricity to power the lasers. And then the fire better produce enough heat to produce enough electricity to power the lasers...
So far as I am aware, coal, oil, gas, and nuclear power stations all generate electricity by producing heat, boiling water, and using the steam to spin a turbine. Once you have heat, the rest seems like well-understood industrial technology. Is there something unique about fusion power which makes its heat more difficult to employ?
Yes, the fusion needs "huge" amounts of electrical energy input to happen, be it in the form of lasers like here or in the form of magnetic fields like in iter.
In this experiment 2.1 units of input energy produced 2.5 units of output energy. That energy has to be converted to electricity. Conversion looses like 40% of energy (escapes unsused) – so you have produced 1.5 units of electricity from 2.1 units of electricity input.
Sure, that's always been the challenge with fusion. I mistook you to be implying that there was something uniquely difficult about generating electricity from heat produced by fusion, but now I suppose you were simply describing the overhead involved.
>In this experiment 2.1 units of input energy produced 2.5 units of output energy. That energy has to be converted to electricity. Conversion looses like 40% of energy (escapes unsused) – so you have produced 1.5 units of electricity from 2.1 units of electricity input.
Thanks for distilling this into one three simple sentences, I know from my brief career in science policy how hard that can be. (You should write 1 pagers for the US Congress :-))
To get back on topic:
So basically, if I'm understanding you correctly: this is an increase in efficiency but not one such that it makes sense economically to generate power in this way?
Is this a large jump in efficiency from previous attempts?
The reason I ask is that I know physics can be incremental, so I don't want to detract from the contributions of the authors... and by all means, it's the type of thing I'd expect to see on HN if so and I'm glad it was shared.
I was just surprised to see many more mainstream sites, geared towards a more general audience, running stories about what I'd expect to be more of a niche discovery.
(Possibly as more of a geopolitics thing -- much like if someone is arrested no one recalls with equal vigor when the charges are dropped, a PR-y article about a minor but important discovery can influence public opinion and be a tool of geopolitics.)
It's not that it's difficult, its just that it's not perfectly efficient. So once you include the inefficiencies of the heat engine it not necessarily producing energy on net.
But there are also some engineering challenges to work out in employing heat generated like this to drive a heat engine, at least with somethings decent like 30% efficiency.
Other sources can do better but the problem of transferring heat from plasma erupting in a vacuum chamber lined with mirrors seems really hard to me compared to the problem you have in a natural gas power plant, say, so I'd expect even a well developed laser pulse fusion power plant to have a lower efficiency.
I recently heard the idea that the price of energy is going to start approaching zero from Chamath Palihapitiya on Lex Fridman's podcast. It hit me as a big, all-changing thing. If fusion is really solved, we can probably mass-produce it within years if not months, so we should start thinking of the implications now
You (or maybe Chamath Palihapitiya) are making a very very wrong assumption that a working fusion power plant would produce free energy.
Nothing could be further from the truth: with any half-way plausible design today, fusion power will be the most expensive form of power generation known to man. While some of the fuel is nearly free (deuterium and to some extent even the tritium), it's more realistic to think of the reactor itself as the fuel - since the reactor will be under constant very high energy neutron bombardment, it won't last for more than a few years, maybe a decade at best.
And since a fusion energy reactor will be one of the most highly advanced engineering accomplishments in human history (it requires extraordinary structural resistance to hold up the necessary equipment in the presence of the gigantic magnetic fields, extraordinarily advanced magnets, a blanket of liquid lithium and boron that gets pumped continuously and somehow recycled etc.), having to rebuild one every 10 years will be extraordinarily expensive (and we should expect something closer to 2-5 years for the initial designs, even assuming no explosions).
In contrast, a fission reactor is already extremely expensive, but has similar output to any contemplated fusion plant, has been proven to be able to be continuously operated for >50 years once built, and requires only slightly more expensive fuel (uranium is really not that expensive compared to its energy density - certainly nowhere near as expensive as gas or coal).
Edit: oh, and this seems to be related to a breakthrough at the NIH, presumably on their inertial-confinement fusion experiment, which (despite some rosy rhetoric) is a weapons research program, with no realistic possibility of ever being transformed into a fusion power plant.
I think he was talking about decentralized grids & renewable.
Let's talk about fission - I used to say I'd build 70,000 nuclear reactors if I was in charge of a rich country. Would I have enough fuel to power them all?
Your third paragraph painted a pretty vivid picture in my head, good writing.
The price of energy has always been approaching zero. Restated, the amount of energy available to an individual has generally grown exponentially, with pauses here and there because civilization. We might be resuming that growth in the next few decades.
Fusion isn’t and won’t be solved in the immediate future. There is a long path towards commercial viability and a lot of milestones along the way… and not really a great method of associating them in a popular science sort of way that doesn’t seem like “we’ve solved fusion!”
Real significant progress is indeed being made and is expected to continue, people are going to be excited then disappointed by milestones being announced because we’re closer but not there.
Fusion isn’t just always thirty years down the road though, we can see the destination getting closer.
I think all progress will accelerate significantly with the dawn of true AI. The fusion scientist can now ask ChatGPT for ten (or 10,000) ideas on how to solve a particular roadblock, and a lot of the suggestions will be actually good. The cost of intelligence has suddenly become near-zero, and that will supercharge everything to do with innovation
LOL, no. Asking ChatGPT is no different than just googling the question, except the answer is more nicely formatted. ChatGPT has no actual intelligence in it.
"The fusion scientist can now ask ChatGPT for ten (or 10,000)"
Since the ChatGPT can't perform empirical experiments and update it's suggestions based on those experiments it has no way to tell a "bad" idea from a "good" one.
Don't get your hopes up yet: This just demonstrated that the released energy (in form of heat etc) is higher than the energy input – yet the released energy hadn't been converted to electricity that could have powered the lasers.
Supposedly this would be done by a heat engine, with can normally extract 60% of energy input. So 2.5 * 0.6 = 1.5, so it is yet again not producing any surplus energy.
More importantly, laser efficiency is around 1%. At "scientific breakeven" you create more energy than the laser delivers. To make it a viable energy source you need to produce at least 100x more energy from a single pulse than scientific breakeven.
In many jurisdictions the cost of delivering a kilowatt-hour is already more than the cost of producing it. So cheap energy is not going to have a substantial impact on normal people unless we switch to wireless electricity delivery or something.
Not just cheap though - near zero. If we have an infinite tap of it, we can afford to waste a lot of it in the process of delivering it. The inefficient becomes efficient when you plug in infinities and zeroes
Even if fusion heat is free, it still costs significant amounts of money to convert heat into electricity. Most of the cost of a coal plant is converting heat into electricity, and the last coal plant built in the US cost $600M to build.
Energy costs might drop an order of magnitude, which is significant, but isn't going to cause any sort of systemic change.
Who's we? If fusion is solved, the country that has will just become a net energy exporter (somehow, if it's the US, idk how they would ship that power). Nothing much will change for the rest of the world, they will just switch from one dependency to the other.
Interesting point that I hadn't considered. I just automatically assume that when fusion gets invented, it will be shared with the whole world so we can all partake in da utopia... but maybe it will be hoarded instead :(
Energy transport over long distances is difficult and inefficient iirc. While sone energy storage ships well (like hydrogen) it’s unlikely that there’ll be intercontinental electrical lines. Not an electrical engineer so happy to be told I’m wrong.
Good work, but IMHO we're still a long way from using fusion for energy, if ever, even if only because it will be so expensive to build and run these ultra-high-tech plants. But also because of all the downsides of D-T fusion, like, where is the tritium, and that most of the energy comes of as fast neutrons, etc.