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The net energy gain is very slim and has to be converted to electricity to power the lasers – in doing so, there's so much loss, it is again NEGATIVE. It's always the same…
As it always is with new, unproven things.
There are always these articles: net energy gain finally! and then: no not really.
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Solar and batteries are already cheaper than fossil fuels in most markets. Nuclear isn’t competing with renewables, it’s competing against batteries and almost free renewables that charge them. Nuclear is still possibly a great fit for niche locales where renewables aren’t feasible at all. Not a nuclear hater by any means (we need every innovation we can get), just show your math. https://www.science.org/doi/10.1126/…
Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).
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Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).
Why do we need to cover the worst case with 100% renewables? The goal is to reduce emissions so it would be great even if we can just stop burning coal in the summer.
It's one of those issues the overwhelming majority of people are on the same page about what we should do but at the ends you have "my livelihood depends on coal" on one end and "my life is insulated against the downsides of full-renewables so I'm privileged enough to have out of touch opinions" on the other and that's who shows up in comment sections.
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Not an engineer in this field, so I may have misread/misunderstood, but I read that 2.5MJ out for 2.1MJ of laser energy in, NOT the total energy needed to make the whole thing work.. So, in a layman’s world, it is not a net gain of power, only a small subset of the system yielding more power than it took in. Happy to be proven wrong and told that it is more of a breakthrough than I think it is..
No, you are correct.
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Are solar + batteries feasible to heat every house in Minnesota with electricity when it's below -20F (-30C) for a week, we have > just show your math. I admit I can't. It's mostly gut-feeling from various science news sources I keep up with (e.g. Ars Technica; Skeptic's Guide to the Universe).
I wonder if we should seriously consider moving people away from such cold climates and towards warmer ones. Air conditioning is cheaper and coincidentally happens at about the same time as maximum solar power.
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> They got what, 2.5 megajoules out of 2.1 in? Of laser energy into a tiny control volume that doesn't consider how much energy went into the laser systems. If you draw the control volume around the building and see that the lasers require vastly more energy than what came out, I think you'll be less excited, right? We've been getting lots of energy out of fusion since the early 1950s with thermonuclear bombs. We kno…
Could you elaborate on that? What do you mean that the lasers could require more energy? Is it that in a specific volume they got X EM energy coming in from the laser and Y thermal energy coming out, with Y>X BUT the electricity consumption of the lasers is Z>Y>X? If so that's sort of misleading, like the plethora of claims from ITER. I hoped this was different.
But personally, I don't know whether that's actually important. Power plants usually consume a nontrivial fraction of their own produced power to power themselves, and in fact consume more than 100% of produced power when starting from a full stop — meaning that in initial few-shot conditions, even when feeding back their own produced power into themselves, they still need (huge amounts of) external power input to get going, like a car engine needing a battery + starter motor. Only a rare few kinds of power plant can be used to "black start" a power grid. Most types of generator need to overcome initial higher resistances, e.g. inertia (and thereby back-EMF resistance at the transformer) in getting heavy turbines spinning from a stop.
It wouldn't be at all strange if a practical fusion power plant turned out to be energy-negative over a few-shot run (i.e. required "bootstrapping"), but then became energy positive over a theoretical 24/7 run at whatever its optimal duty cycle is. And a single-shot run becoming net-positive would be a good point to start to consider those more practical calculations, since they'd have been useless to consider until then—a power plant can't possibly be net-positive over any kind of runtime + duty cycle, if its core reaction can't be net-energy-positive when considered in isolation.
Which is, to me, why it probably does make sense for ITER to be excited. They've reached the point where they can stop using a lab-bench model of power efficiency, and start trying to come up with another, more full-scale model of power efficiency to replace it with.
The net energy gain is very slim and has to be converted to electricity to power the lasers – in doing so, there's so much loss, it is again NEGATIVE. It's always the same…
This isn’t the same; this hasn’t been done before. New things are hard. Nothing truly worthwhile is easy.
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I think fusion-plants have always been "15 years away", and most likely will be so for quite a few years... Edit: I was wrong, fusion is always 30 years away: https://www.discovermagazine.com/technology/why-nuclear-fusi...
I don't know what people get out of repeating this on every single fusion article. It's not inventive or insightful, and it doesn't further the discussion in the slightest.
Because we simply cannot live in a world where we are independent from the current power structure. They won't allow it.
Hopefully I'm wrong, I'd love to see progress in energy production that is actually sustainable.
After a few more major breakthroughs we'll be where fission was in 1942 after Fermi made the first man made neutron chain reaction. After that, we can see what a practical electricity producing plant looks like, and see how much people actually care about small amounts of tritium radiation. At the moment fuel costs in fission are like 5-10% of total costs for a fission fleet. In fusion it could be lower, but that wil…
It's still decades off but as I understand it, this was the hardest nut to crack. They got what, 2.5 megajoules out of 2.1 in? I might be in the opposite camp as you but this is very much a "where were you when—" moment for me. I'm sure someone will pop in to disappoint me but I think the point is it's no longer a hypothetical exercise.