[Schroedingersat]

Any amount of primary energy consumption that covers more than the already built up areas or the land currently used for fuel ethanol with solar will rapidly cook the planet through nuclear.

Current primary energy is 18TW. Total insolation is 170PW. GHG forcing is about 200TW. We can provide enough solar with smaller than a 1000km square. More than that will kill us no matter the technology used (but solar is better than most as the total heat it produces is a bit more than the work done rather than 3x).

Growth must end or physics will end it for us. Climate change is the warning shot across the bow, not the full volley.

[wefarrell]

"Total insolation is 170PW" - That assumes 100% efficiency, it's from the upper atmosphere, and making full use of it would mean there would be no light left for plants or the ocean. After accounting for solar panel efficiency, battery efficiency, and the amount of surface where it's possible to put panels without displacing nature and agriculture it'll be somewhere in the low hundreds of TWs.

"Current primary energy is 18TW" - That's outdated and only consists of the energy converted from electricity. It doesn't include non-electric heating, driving, maritime transportation, aviation and freight. Taking those int account our total consumption is around 100TW.

[Schroedingersat]

> That's outdated and only consists of the energy converted from electricity. It doesn't include non-electric heating, driving, maritime transportation, aviation and freight. Taking those int account our total consumption is around 100TW.

That's what primary energy means (as well as the heat wasted from allof the above). My best guess as to how you got 100 is you're mixing up 160,000TWh with TW

> That assumes 100% efficiency, it's from the upper atmosphere, and making full use of it would mean there would be no light left for plants or the ocean. After accounting for solar panel efficiency, battery efficiency, and the amount of surface where it's possible to put panels without displacing nature and agriculture it'll be somewhere in the low hundreds of TWs.

I wasn't implying all of that was available, merely that around 0.1% of that in thermal forcing is enough to be a problem on the same scale as GHG emissions. Wind is the technology which produces the least new heat (none, although if you exceed around 1W/m^2 for too large an area you change the climate in other ways), followed by solar on existing asphalt, grass, or water (up to ~1W of new heat per watt).

Any thermal fuel that didn't recently come from sunlight is in the 1.4 to 3 range (excluding extraction and processing).

This caps primary energy around 400TW for renewables or 200TW for nuclear (with only around 70W as work if you are using a steam engine).

Nuclear provides less end-state access to abundant energy on earth than renewables at higher cost. There is no reason to pursue it.