ajmmsr t1_jaqr4hs wrote on March 3, 2023 at 11:16 AM

Reply to comment by SandAndAlum in Electric world that kicks out fossil fuels will cost less than combustion economy. 30TW of wind and solar PV will take 0.2% of earth's surface. by DisasterousGiraffe

TW is power so multiply by a time to get energy

Here’s my reference to USA energy https://www.energy.gov/sites/default/files/2022-08/Energy_2021_United-States_0.png

Don’t know what you mean by ‘net’

SandAndAlum t1_jaqrcr1 wrote on March 3, 2023 at 11:19 AM

30 * 8.760 is 260 not 26.

Net implying average output over the year. Ie. A 3.3kW nameplate tilting solar system in California is 1kW net. Primary energy is input, final energy is what is achieved. A 25% efficient gas engine running on tar sand oil with an EROI of 3 needs about 6kW of primary energy for 1kW of output. The 500GW or so of primary energy powering US transport can be replaced by 100GW of electricity. Similarly 200GW of gas heating can be 50GW of electric heat pump.

If the 30TW is nameplate then the capacity factor cancels some of the waste heat, so it's merely 10x what the US uses not 30x.

ajmmsr t1_jaqs9iv wrote on March 3, 2023 at 11:31 AM

Arrrgh

Yeah 262PWh at 100% capacity factor

Since wind cf is about 30% That’s 78.8PWh of energy, so 2.7 times the USA energy.

No where in that article does it mention nameplate

SandAndAlum t1_jaqsy07 wrote on March 3, 2023 at 11:39 AM

It's ambiguous then as to what cf they mean.

New western offshore wind is in the 40-50% cf range. EU solar is 13% so there's a big range there.

10TW net final energy to replace existing 18TW of world wide primary energy and cover some growth sounds pretty close to most ballparks so 30TW of 30% cf sounds reasonable.