4 ms·
Maybe, but the heat added to earth has to be radiated away from earth. We have never added energy from matter at this scale before. Same for fusion.
by bullen 3y ago
Maybe, but the heat added to earth has to be radiated away from earth.
We have never added energy from matter at this scale before.
Same for fusion.
- defrost 3y agoYou really should look up the daily energy reaching the earth's surface from sunlight and compare that to annual total energy use by humans. The vast majority of daily solar energy is radiated away already and it dwarfs human energy consumption. Climate change is a result of human activity adding more insulation (via C02, methane, increased water vapor) to the atmosphere and trapping more of the energy from the sun that would previously have radiated away. The increasing global average tempreture is caused by humans adding more blankets .. not by humans adding more heat under the existing blankets.
- zapataband1 3y agoInteresting way of putting it, thanks for the explanation
- a3w 3y agoAFAICT, you are probably wrong. Here is some points as to why: > daily energy reaching the earth's surface from sunlight ... which is exactly the same as the amount of energy radiating off, in a state of equilibrium. But here comes the problem, if we add heat, e.g. from fission, we are not in an equilibrium anymore, are we? Skeptics of anthropogenic climate change make that claim all the time: Absolute numbers are huge, so they do comparisons like - 99.998% if Carbon does not take part in Carbon Cycle, or - heat radiation from the sun is more than X by a scale of Y. But in balance, so any addition without compensation can compound to be fatal to human life on earth. After increasing the temperature by storing energy, then radiation off the surface and air layers will increase. But the heat build up is strongest at ground level, yet radiating to space is hardest from that layer. So the effectiveness of heat dispersal in a layered, in-vacuum geoid is not ideal. > Not only[addition by me] by humans adding more heat under the existing blankets. Volker Quaschning hat an article, in german, on that. A comparable, unfavourable look on heat introduction instead for a post-co2 energy generation, was also cited in minkorrekt podcast (german, too). But that that is a small factor, too. I did back of the envelope calculation, and - if every of the 8 billion humans increases their consumption to western standards, - their energy from unlimited fusion or unlimited fission, earth still boils. It might be 2-5 % of the effect of greenhouse gases, by heat introduction is real and at scale deadly, too. With water, wind and solar, we have no added heat, since moving gases and fluids evoke heat anyway, which just is not converted to electricity in between. And solar changes the albedo of the place where the panel was placed to a reflectivity of that of a green meadow, which might be worse than some kinds of coating, but usually is better then other roof tiling [citing needed, do IR/VIS-white-painted roofs exist?]. TL;DR: Smaller problem by a few orders of magnitude, but unless dangerous geoengineering takes place[1], still unsustainably cooks mankind. [1]: Please don't. IPCC report says "keep the idea of geoengineering out of media, for it is not a solution but pandora's jar"
- audunw 3y agoI was surprised to learn how significant the heat added from thermal power plants can be for global warming. Without technological improvements a massive scale up of nuclear energy would probably be a bad idea. There are panels that can radiate heat directly to space though. So it has made me wonder if the nuclear power plants of the future could use such panels to radiate their heat directly to space. Essentially they’d be like reverse solar power plants, that also work at night. Wonder if it’s feasible and economical. Personally, I think the future will mainly just be solar, hydro, geothermal and energy storage. As world population decline we’ll end up having more than enough materials if we recycle them. Energy use will go drastically down. Question is if we need nuclear in the transition. And we should have nuclear R&D anyway as we need it for space exploration.
- Matumio 3y agoSeriously? Everything on earth's surface is radiating thermal energy into space. In such a massive amount that you'll feel a distinct temperature drop in a cloudless night. If you want to radiate more heat into space (at a global level), you'd have to start by removing the clouds, or the greenhouse gasses.
- zokier 3y agoThe total energy consumption of humanity is still very tiny compared to the total solar irradiation that earth receives. Maybe at some point that might become a concern, but not anytime soon.
- goodpoint 3y agoTHIS! People seem to forget basic physics sometimes. Any source of free, unlimited "clean" energy would be an environmental catastrophe because energy used is released into the atmosphere as heat. We need sources that *capture* energy already in the environment, like solar, wind and similar.
- goodpoint 3y agoSilent downvotes do very little.
- acidburnNSA 3y agoSee other replies above. Thermal energy emissions pale in utter insignificance compared to the solar heat flux. What matters is things that control what happens with that solar heat flux, aka greenhouse gasses.
- Vecr 3y agoIf that was actually a problem you could use geoengineering to make the planet more reflective overall, letting you use more nuclear power.
- refurb 3y agoGlobal energy production in 2019: 617 x 10^18 J Global energy from the sun per day: 430 x 10^18 J
- rainworld 3y agoIndeed we are 2–3 orders of magnitude away from the point where our energy output itself non-negligibly, globally heats the earth. And if we kept growing, an incandescent Earth would not be too far off. There are hard limits.
- abecedarius 3y agoCurious: for the latter I get 7e21 J, using Wikipedia's normal-insolation figure of 947 W and its Earth albedo of 0.3. That's an order of magnitude greater. I'm probably missing something, do you have a source? (Of course my figure would only increase the difference you're pointing out.)
- goodpoint 3y agoThis does not take into account that the planet was in balance before human activities has started impacting it. Plus earth reflectivity is decreasing due to human intervention e.g. deforestation.