Long term blessing. The effects from thermodynamics and direct heating would be miniscule compared with burning carbon. Yes, we need LOTS of other change too, if we magically had free, carbon neutral energy, we’ve still got to deal with ecosystem collapse, the water crisis, and tons of other stuff. But, i don’t see how it could be anything but good. Technology can’t solve everything, but a lot of the personal responsibility/luddite crowd seems to have the idea that everyone can just stop using energy or needing food which is… just absurd and often classist. So yeah, the truth is, we need a mix of things. Mostly we need to get rid of colonial capitalism but that’s the hardest part of all.
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Just to say, Green Revolution. The increase use of chemical fertilizers, large scale monoculture, farm machineries, knowledge of crops lead to increase in food production, and that lead to increase in world human population. I’d think the Green revolution is not ‘Green’ by today’s standards. It is a name of a time period in the recent past. searchable in wikipedia. It may be part of the Industrial revolution, since Steam engines with Trains and steamships enabled grains, commodities to reach different parts of the world and increase productivity. The invention of Atomic bomb is said to enable a period of relative peace. A few decades, one will never know if WWIII will occur, since many are feeling that nuclear is very safe and clean.
Dyson sphere?
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Essentially, yes, but on the small scale of a fusion reactor as opposed to an actual star.
PV have a hard limit on temperatures they can operate at due to being based on junctions and the fact that all materials diffuse at high temperatures. Plus, I’m fairly sure that all radiant energy would be absorbed as heat, I really don’t think that the reactor is going to be transparent and let everything radiate away, right?
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Fair point. I guess unlike an actual star, the light doesn’t have anywhere else to radiate to if it’s in a contained reactor, and it will eventually be absorbed by something and re-emitted at a lower energy. Still the same thermodynamics determines the theoretical limit for how much work you can pull out of heat energy as for any other part of the spectrum. Someday we may be able to overcome our engineering limitations and be able to match the efficiency of heat engines in photovoltaics as well. If/when that happens, PV might actually have the advantage since there aren’t any moving parts that need replacing as with heat engines. Additionally, we could potentially overcome some of the temperature limitations of photovoltaics if we could miniaturize the reactors. I’m sure miniaturization would present other problems and challenges of its own, but a series of tiny reactors could put out the same amount of energy as one large one while spreading that energy output over a larger area and reducing the total amount of heat each cell is subjected to.
I didn’t actually think about creating an iNat project for our rehab. I’ll have to look into it. I’m not sure what all would be involved because I’m relatively new to iNat and still trying to figure things out. I didn’t even realize there was this forum until a couple of weeks ago!
But thanks for the suggestion. It’s a good one.
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I don’t know too much about nuclear power itself, and this probably only tangentially related, but did you know that nuclear power plants are having an issue where jellyfish keep getting stuck in the intake pipes (pipes that intake water to cool off the power plants).
I have mixed feelings on nuclear power, but I don’t know enough about it for my opinions to have any weight.
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Small problem, the weather, is too hot.
https://www.telegraph.co.uk/business/2022/08/08/why-macron-easing-safety-rules-flood-rivers-hot-water-nuclear/
This is the International Atomic Energy Association FAQ of Fusion: https://www.iaea.org/topics/energy/fusion/faqs .
For what it’s worth, I worked in the massive Bruce Nuclear Power Development (Now the Bruce Nuclear Generating Station) 50ish years ago. At the time there was limited power generation, as most of the reactors were being constructed or in planning, but I got a pretty good look at the nuclear power industry while working there as a summer student for a two or three summers. I went in believing the fission-based power generation tech was safe. I discovered that the problem is that Homer Simpson really does work there. The tendency to minimize perceptions of risk, cut budgetary corners and CYA is as present in nuclear facilities as in any other human institution and their safety is a function of how motivated, well-trained, disciplined and smart their operators are. Nothing terrible happened there, but I saw some attitudes and behaviours that were discouraging.
Fusion is a different thing. If the reactor is operated incorrectly it just shuts off because there’s no chain reaction to get out of control.
As others have said, the impact of direct thermal emissions is very small compared to greenhouse factors.
There are no industrial-scale forms of electrical generation that are devoid of environmental effects. The life-cycle footprint of some so-called green technologies is pretty gruesome by some metrics. As others have noted, it’s about the trade-offs, like most things in life.
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Pretty sure E.O. Wilson knew that Star Wars was science fiction. It’s a metaphor and I’m not sure why anybody would take one of those at “face value”.
There is nothing in anything about Wilson’s quote that is inconsistent with grasping the impact of human numbers on ecosystems. To the contrary, the universal tendency of rational decision-making to be overwhelmed by processes driven by emotions like greed, fear and anger is why we don’t do anything about it. The role of ossified institutions in things like banning or limiting contraception, and obstructing women from controlling their own bodies and participating fully in political and economic life is a global problem that is inextricably linked to human demands on the planet.
If we didn’t have Stone Age emotions, medieval institutions and godlike tech, dealing with the population question would be a whole lot more plausible.
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Current global warming isn’t caused by waste heat bleeding out from our homes, vehicles, and workplaces. It is caused by the CO2 and methane emissions that we generate creating the energy we use now. Emission free energy would undoubtedly result in an increased use of energy but only if the energy companies reduced their rates. Would people really run their AC/heater with the windows open just because they could afford it? Or would people want to spend even less on energy?
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There is a quiet and desperate layer of society that can’t afford air conditioning, or heating.
https://www.theguardian.com/commentisfree/2022/aug/07/britain-social-emergency-leaders-political-vacuum
how do you know this will be cheap? how much does it cost to actually build a fusion reactor and operate it? how much does the fuel needed to spark the reaction cost? (do we even have enough of such seed fuel in the world to get it all going?)
also, who’s going to own and profit from the reactor(s)? how much will they be able to profit? (just because a reactor can produce a lot of energy doesn’t mean that energy will be given away or sold cheaply.)
“best” is debatable. nuclear definitely has some strong positives (relatively tiny physical footprint, relatively few deaths associated with its use), but it also has serious negatives. new generations of reactors are still in development and the old ones are limited by the amount of available fuel in the world. (so it would make no sense to build a lot more of these just to run out of fuel.) nuclear is by far the most expensive ($) major source of electricity. solar is much, much cheaper.
when is the first production fusion reactor expected? a decade? 2 decades? 3? how long will it take to scale up beyond that? is that really fast enough in terms of climate change action?
it always amazes me that we seem to reach first for miracle cures that are perpetually just around the corner, when we already know how to solve the problems but just don’t want to do it. in this case, it starts with cutting down roads and highways and increasing other ways to transport people around. make human places more dense, more interesting, more walkable… and stop subsidizing development of places that aren’t. leave more space for nature.
(you might think i’m confusing consumption of transportation fuels for electricity here, but i’m not. these and many other issues start at the same source.)
i know that’s easy to say and less easy to implement – just like eat healthy, exercise, get enough sleep, nurture meaningful human relationships – but at the end of the day, it just comes down to priorities…
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I don’t like solar in its current form, if it evolves in something better, then maybe, still, having huge fields of those panels won’t be good even if making those panels weren’t as dirty as it is now.
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From the IAEA Fusion FAQ to which I linked above:
At present, fusion devices produce more than ten megawatts of fusion power. ITER will be capable of producing 500 megawatts of fusion power. Although this will be on the scale needed for a power station, there are still some technological issues to address before a commercial power plant can operate. A prototype of a fusion reactor (DEMO) is expected to be built by 2040.
I much prefer putting the solar where it is needed. On the roofs of … office blocks, schools, hospitals, shopping malls. Instead of over there, out of sight, then with transmission lines. A profit solution with huge fields, rather than a human solution where it is going to be used.
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10+ MW thermal power for a few seconds, and i think in that case, the output was something like 0.33x the input power.
for bursts of 5-10 minutes. during those bursts, ouptut is supposed to be 10x the input, but that’s still far from production plant. best case, you get good results and proceed to the DEMO reactors. worst case, you use up all your world tritium supplies and have nothing but a bunch of radioactive steel, concrete and other stuff to deal with, along with a bunch of DEMO projects in design/construction that will never be useful.
yes, there are lots of DEMO plants being designed, but these are not production plants either. as far as i can tell, the first actual production plants are planned for 2050. that’s assuming a whole host of difficult technical challenges can be overcome… and also keep in mind that we would need a lot more plants than those first production plants, and it’s not clear that it will ever make economic sense to build and operate a lot more such plants.
…
i’m not trying to poopoo the whole idea of fusion, and it’s definitely worth trying to go down the path, but my earlier point was that we know how to solve solve existing problems with existing solutions. but instead of taking the inconvenient actions that are needed, we pin our hopes on solutions that few people really understand which – even if they do materialize in the distant future – probably will not materialize soon enough.
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I am an electrical engineer. In around 1970 I had dinner with a prominent nuclear engineer who stated practical fusion power was 20 years away, and it still is.
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Understood. You posed a question and I posted some relevant information from a link I had provided earlier.
As I said upthread in reference to a quote from E.O. Wilson in a slightly different context,
The hard-wiring of our limbic systems and social and institutional arrangements weighed down by assumptions and relationships that have nothing to do with modern life in the technological age are at the root of our collective failure to do what needs to be done. Confronting that in a constructive way is no easy job.
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