Speaking of that... When people talk about limitless cheap energy from fusion reactors in 30-50 years, I wonder about goal warning from water great from all that energy consumed and turned into waste heat radiated into Earth's atmosphere.
That will be a problem in a few hundred years of our energy consumption continues growing at this rate; I've done the math on this website a year or two ago.
At the rate our energy consumption is growing, even if we avoid climate change wrecking our society today, the heat waste of our energy production will start to eclipse the effects of climate change in only a few centuries, at most a millenium. Which isn’t that long of a time.
You can get pretty far by being extremely efficient. We keep making better and better superconductors and even have some above room temperature. Vac-trains with superconducting maglev is more efficient, in principle, than anything short of orbiting. Better materials can make dry mass near nothing.
Reversible computing requires no fundamental energy input.
Space based solar power could make sure the waste heat from electricity production is almost zero and only useful energy is pumped to the ground.
You can shade the Sun at the limit. And you can shade only the portions of the spectrum that are not biologically active, i.e. shade infrared. That's tens of Petawatts.
You can also literally build radiators at high altitudes to dump waste heat into space before it gets conducted into the atmosphere.
You can also just do more work in space instead of on the ground.
I think also we won't grow exponentially but instead linearly or quadratically. That's actually sustainable for as long as the universe would've lasted anyway.
Depends on the source of energy production - if we're drawing all our energy from solar and wind, then we're not introducing new energy into the earth. That's the problem with fossil fuels - we're reintroducing sequestered carbon into the atmosphere; if we were to burn wood instead and keep the carbon cycle in balance then it wouldn't be an issue. Nuclear energy does introduce new energy though, so that could cause issues.
That's actually not true. If we use solar energy, we are reducing the albedo of the earth, thereby introducing more energy than otherwise.
As far as wind, you are correct, but the amount of wind energy we can harvest is limited enough that there simply won't be enough at that point assuming that trend.
Similarly with wood, at that point we would just run out of wood.
Question-are we reducing albedo with solar? Solar cells appear more reflective than soil; I wouldn't think that albedo would be reduced unless we were putting solar cells over the ocean. Do you have a source for this, that's an interesting conundrum but seems counterintuitive. I would think that solar cells actually reflect more heat than they absorb, I have had to work around them and they act as though they reflect more heat than soil. If you can back that claim up, I'd be really interested in reading more.
Are you accounting for population collapse? Increased energy consumption corollates to wealth correlates to below-replacement birthrates.
If that doesn’t solve the problem, a culture capable of generating and using that much energy will just build space colonies, which solves the problem too.
That’s the only potential way out, yes. We’ll need lower population on earth, but to continue our current speed of scientific progress we’ll need the same or an even larger population overall, so we’ll have to move into space (the final frontier, these are the voyages…)
It’s not sustainable with our current consumption standards, especially considering AC usage, space usage for single-family homes, and meat consumption.
If everyone was a vegetarian living a dutch lifestyle we’d have no issue, that’s true.
We're capable of developing and building out abundant energy production over the next century if we want to, and doing so is going to be a far preferable option to deliberate material deprivation.
I can't find it, sorry. You can reproduce it, though, just increase energy consumption exponentially by 1.04 or so until it reaches 1-2% of the insolation from the sun. I had done it a different way but retrospectively this is easier and better.
The energy we produce is still a minuscule fraction of the energy we receive from the sun, so it will be a long time before that will be an issue. Also, I'm increasingly doubtful we'll see practical fusion energy in this century. We'd better focus on using the energy that's already here: sun, wind, etc.
