If humans really had "unlimited energy", we could air condition the entire world, and send the waste heat to space with large infrared (or even visible light) radiators.

At some point potentially soon if you want really good economic growth you have to decouple economic growth from energy growth. That is a step more fundamental than decoupling energy growth from coal and oil.

Not really. Air conditioning is a heat displacement system, so you'd still have the same amount of heat. Using infrared radiators would just accelerate global warming since green house gases mainly absorb infrared light.

Visible light would probably be a hazard. Would be pretty great for "beam in the sky" special effects though.

I think she was suggesting sending the exchanged heat into space..you know, up.

It's heat, you can't send it anywhere except by thermodynamic processes. You can't beam heat to space. A beam of infrared is not heat, it is high quality free energy.

Let's say we point that beam at the moon. The Moon gets warmer. So in this thermodynamic system Earth-Moon if Moon gets warmer, the Earth gets colder.

Since we're talking about solar power, this is not a huge concern.

I wonder if it's feasible to mitigate the waste heat radiation problem by combining photovoltaics with thermoelectrics?

meh... people have been screaming DHOOOOOOOOOM!!! for generations upon generation...

We'll never make enough food... we'll never have enough energy... we'll never get along...

Things are always bordering on the end of the world yet we survive.

"Survivorship bias or survival bias is the logical error of concentrating on the people or things that made it past some selection process and overlooking those that did not"

Which human species didn't make it past all of the previous catastrophes they predicted?

Those that didn't are largely not around to let us know whether or not anyone was raising the alarm.

https://en.wikipedia.org/wiki/Maya_civilization

https://en.wikipedia.org/wiki/Rapa_Nui_people

Which INTELLIGENT species didn't make it past all of the previous catastrophes they predicted?

...all the ones we never heard of.

Prior returns don't guarantee future results. Have you considered that people have taken steps to avoid catastrophy.

Granted, it only takes one "failure"... but... "people taking steps" is exactly what I was alluding too...

Time and time again, cries of "Too many people!!!"... how will we feed 1 billion people?

Advances in farming, logistics, technology, etc...

What's being done now? More advances in farming, vertical farming, AI, etc...

That depends on the nature of the threat. Running out of feedstock for plastic? Not a problem. That's the sort of thing for which one can assume a technology fix will happen, and there is probably plenty of time. On the other hand, missing the population slow-down projections and ending up with a 20 billion population? That's doom, and there is no techno-savior.

"ending up with 20 Billion Population? That's doom, and their is no techno-savior"

Except for advances in vertical farming, green energy, advances in urban planning allowing people to live denser and more packed together...

We'll all be dead because earth can't handle the population... cira'1968:

https://www.nytimes.com/2015/06/01/us/the-unrealized-horrors...

"Dr. Ehrlich was so sure of himself that he warned in 1970 that “sometime in the next 15 years, the end will come.” By “the end,” he meant “an utter breakdown of the capacity of the planet to support humanity.”

So... by 1985, we will all be dead because DOOM!!!

Time and time again...

Now... can we all "get along"? Christians, Muslims, Chinese, Russians, etc? THAT isn't a technology problem - that's a humanity problem.

Can we feed everyone? We sure can... and advances in tech continue to push the envelope and there is no reason to believe that we can support many multiples of what we have now.

Is there an upper limit? Undoubtedly... are we near it? Hardly...

A population that's 2X the fairly optimistic projections of global population growth slowdown roughly double energy needs, at a time when, at best, renewable energy faces both enormous opportunity and enormous challenges in replacing coal and oil, and when cutting greenhouse gasses is critical to human survival. Just making that twice as large a challenge is reckless and dices with extinction.