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Comment by cronix | Hacker News Reader

Stuff like this just boggles my mind. Imagine if we could capture/store even a small fraction of that energy that was released in mere seconds. It could probably power Earth for millions of years. Sorry if my maths are off a bit.

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The energies of even less exotic stars are insane. If we could capture 1 second worth of our sun's output then we could power earth for almost a million years.

The earth already does that, we just call it our ecosystem. It's why we have clean water, carrots, coal and, and the end the chain, the internet to talk about it.

They are talking about capturing the full irradiance of the sun for 1 second. You are talking about the little sliver of it that smacks Earth.

True, but it's enough. We don't need more that what we already got. We don't even use most of it.

No, we need more. The main barrier to achieving the dreams of science fiction is a lack of energy to accelerate human-scale amounts of material to high speeds (then slow them down later).

I'd add that we not only want, but need, space travel in order to maintain the species. Once our sun or planet dies we go with it, unless we're on a different one.

Not just that even more mundane stuff becomes much easier if you have more energy - clean water (desalination), trash (vaporize & collect fractions), raw materials (can trade energy for lower input concentration in ore), polution & greenhouse gases (capture back from th atmosphere and convert to something usable or inert).

All this becomes relatively easy if you have a lot of cheap power. And you would not get it just by power saving and eficiency improvements, only with research and building of new sources.

No, we need to use more of what we get. We don't use hardly any of what hits the earth. I believe I read that the Sun supplies 50X the amount of energy we consume (if of course we could capture it as energy).

You are off by a few orders of magnitude, the amount of sunlight hitting just new mexico (after taking into account the losses of converting it to electricity) is about 50x the energy we consume.

Worldwide?

We're actually getting a bit more than we'd like. If we could get the sun to turn it down a smidge for a few hundred years while we get the gas mix in our atmosphere right it would be most helpful.

If you actually did this, the surface of the Earth would melt or catch fire.

>we could power earth for almost a million years

With current consumption only. But we will populate its every corner, waste every amount on food production and fantasize what if we could capture just ten seconds a year (and terraform Moon/Mars). Humanity is a virus that cannot stop eating, reproducing in mass amounts and converting their host into a stinky factory.

I really doubt that so called Type II civilizations with Dyson spheres are a paradise to live in. Really advanced creatures would simply reduce their demand and live in the same beautiful place instead, occasionally feeding surplus energy to their scientifical interests.

>Really advanced creatures would simply reduce their demand and live in the same beautiful place instead, occasionally feeding surplus energy to their scientifical interests.

Which works right until an asteroid strikes their planet, a gamma ray burst sterilizes their solar system or a more aggressive species eats them all. The universe is in no way nicer, calmer or more pleasant than the earth itself and look what the earth has produced.

Supply and demand would rapidly reduce this timeline even at incredible energy amounts. There is a virtually unlimited demand for energy. We'd build more energy intensive machines if the supply was so vast. Powering millions of large fans to break up a tornado or a hurricane would now be possible. We'd keep inventing power hungry ideas until balance was restored.

Theoretically we'd eventually cook the Earth with waste heat since energy is never lost so there is an upper limit for energy usage on the planet. Off Earth, not so much.

According to a number of physicists I've talked to, at our current rate of energy release this is already a concern. I've heard that we'll need to worry about this in the next 300-400 years.

In a hand wavy way, we already access the energy from stellar explosions, that's when uranium is naturally produced.

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