761–770 of 833 posts
Here are the numbers from the current live discussion : https://www.youtube.com/c/EnergyGov/live 300MJ in at the wall, 2MJ produced at lasers (using 1980's laser tech), 3MJ out from reaction
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Here's the thing: In order to make inertial confinement work, this process needs to occur multiple times per second All the fancy stuff with the hohlraum, magnetic compression, target cryo cooling must be accomplished accurately and repeatedly, BUT ALSO shot out of an "injector" to fall precisely into alignment with the lasers, in vacuum within a plasma field... When you write it all out! Yikes! Then! This has not in…
All of the problems you just described are solved for in EUV lightsources for lithography on chips at 100khz or more. These are less hard then you make them sound. https://www.youtube.com/watch?v=5Ge2RcvDlgw Probably the hardest part is making sure the droplet is cost effective enough that we care. Again, to op's point, this is an incredibly shallow analysis. The question I would be pushing towards is: What are the h…
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NIF people like to call this the “target gain”, but someone there has been whispering “net gain” to the journalists, in their ongoing campaign of deliberately deceptive hype. But “target gain” isn’t even (pellet output)/(laser output). The denominator is laser energy deposited in the hohlraum; the rest of it doesn’t count. And this deposited laser energy is estimated based on a model of laser deposition—it’s not meas…
> The modeling codes are classified What is the justification for keeping it classified?
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…
Yeah and with a breeder fission reactor we could reduce this to below 1% probably. With a thorium breeder the fuel cost might be essentially 0%. In the vision of Alvin Weinberg you literally just drop some thorium into the fuel salt every once in a while.
But the real issue for nuclear energy is currently capital cost and time not fuel cost. And capital cost can go down massively with GenIV reactors as well.
So I don't see how fusion will be cheaper.
> In fusion it could be lower
But eventually you have to start breeding tritium, so wouldn't that make it more expensive.
> Disclaimer: I switched from studying fusion energy to advanced fission 16 years ago.
Awesome, we desperately need GenIV reactors (even if I dislike that term).
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All of the problems you just described are solved for in EUV lightsources for lithography on chips at 100khz or more. These are less hard then you make them sound. https://www.youtube.com/watch?v=5Ge2RcvDlgw Probably the hardest part is making sure the droplet is cost effective enough that we care. Again, to op's point, this is an incredibly shallow analysis. The question I would be pushing towards is: What are the h…
This is unlike an EUV light source in that once the fusion begins, ideally you don't even need the lasers any more; the fusion from pellet (n) ignites pellet (n+1). Getting that to work is probably orders of magnitude more difficult than what just happened.
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>Converting heat to electricity is expensive. And? Most of our power usage is not supplied through electricity. Solar panels are never going to heat my house.
Why not? Plenty of places have enough sunlight to do so even in winter. Parts of Alberta have similar sunlight mid winter to PNG mid summer. Plus storage is a thing. Using a heat pump to dry NaOH or melt Sodium Acetate, or heat a large pond can store low grade heat economically for months. Ammonia, or methanol can do so indefinitely. Then there's transmission. HVDC can transport energy 10GW pernline for thousands of…
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Personally I think fission power's failure is a political and marketing one. I don't agree that the waste disposal issues, or the safety issues, are quite the big deal people make of them. (Not saying there are no unsolved issues, just that the issues that exist are not significantly worse than those present burning fossil fuels, and are better in some dimensions. They're just different, and in some ways very emotion…
> Personally I think fission power's failure is a political and marketing one. I think it's because of the occasional catastrophic failures that spatter our short history with the technology. Fukushima made headline news around the world, leaked large amounts of caesium-137 into the ocean, caused a 20km evacuation radius, is projected to take a total of 30-40 years to clean up, and people think of it as not that bad…
> caused a 20km
Questionable if that is actually necessary or just over-reaction.
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Literally everything has diminishing returns because nothing is infinite. Edit: to clarify, lasers will have some maximum efficiency that is less than 100% and approaching that maximum is subject to diminishing returns.
Diminishing returns usually applies if you assume there are no major breakthroughs. Can we assume that there won't be any major breakthroughs in this field?
I wouldn't bet on no breakthroughs happening in laser efficiency, but more efficient lasers doesn't look like it will be enough to get to net energy given other inefficiencies in the system.
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You claimed solar has too low EROI to be viable. Prove new solar in a median location is lower EROI than the median for new gas using up to date info on the whole process and solar cells you would buy for a project started now such as 155 micron wafer mono PERC.
>You claimed solar has too low EROI to be viable. Nope, I said that it's lower than other sources of power, and thus an energy economy based on solar will look very different than what we currently have. Given that electricity represents a relatively small percentage of our power usage, in the majority of cases (materials manufacture, industry, heating, etc), the EROI of renewables will be worse than fossil fuels.
Then add heat pumps and PV+Heliostat or PV+CSP derived hydrogen compounds to your equation and realise that adding heat and chemical stocks shipped from distant places to the equation makes it favour renewables even more as you can turn 120MJ of electricity and 40MJ of direct sunlight at Chile's 35% capacity factor into 120MJ of hydrogen or 100MJ of Ammonia you don't have to refine. With the heat pump you'd get more low grade heat even if you burnt the fossil fuel for electricity.
Wind + PV is a pure upgrade from an EROI perspective, and electrolysers and CSP are following very close behind.