Oilpan4 wrote:According to the IEA the US generated 1.2 Terra watt hours in 2017 with coal.
That would require about 240 Terra watts of installed PV capacity and a battery to store some of it.
Your numbers and PV replacement calc are way off.
What is U.S. electricity generation by energy source? In 2017, about 4,034 billion kilowatthours (kWh) (or 4.03 trillion kWh) of electricity were generated at utility-scale facilities in the United States. About 63% of this electricity generation was from fossil fuels (coal, natural gas, petroleum, and other gases).
Second, a well sited, single axis tracked utility PV array is good for about 2.5 kWh annual generation per STC watt.
Well sited on-shore wind produces about 3- 3.5 kWh annually per rated watt
Off-shore wind, about 4 - 5 kWh annually per rated watt
10^6 Mega = million
10^9 Giga = billion
10^12 Tera = trillion
10^15 Peta = quadrillion
Starting from 4.03 * 10^12 kWh annual US electricity generation,
63% is from fossils, = 2.54 * 10^12 kWh annually
Which rather conveniently then requires 10^12 watts = 1 TW of PV
If we predict equal shares of PV, on-shore and off-shore wind the average yield will be 3.4 kwh annually per watt installed,
And thus 2.54/3.4 TW = 0.75 TW = 750 GW required to replace the fossils currently used in electricity production.
In 2018 the US installed ~ 18 GW of PV/wind
In 2018 China installed 50 - 60 GW of PV/wind
Only politics stands in the way of increasing production way above 2018. I'm sure your teachers would agree.