Recently I've seen a lot of commentary on energy choices - what makes sense given a variety of constraints. There's some good information but also a lot of obfuscation and muddled thinking. I probably should post more in the future, but here's the best high level chart of US energy consumption by source and sector. If you go in deeper than this you need to read quite a bit to understand the models and assumptions, but this is as clean as it gets in a simple view.
Some of the more unusual misdirection is calling out wind as bad due to concrete in construction. Here are some full lifecycle numbers for various forms of energy production in grams of CO2 emitted per kWH of electricity generated before it hits the transmission infrastructure.
coal (US) 980 (average for US coal types)
coal (China) ~ 1200 (optimistic)
coat (India) ~ 1200 (optimistic)
natural gas 465 (this does not include GHG from NG leakage in mining)
__________
for the following embedded carbon is added while the fossil fuel numbers above ignore it.
nuclear 12
PV 14 - 40 (many factors here - scale tends to win)
geothermal 20-50
biomass 40-250 (lots of dependancies and assumptions here. Many, myself included, feel it shouldn't be considered renewable)
offshore wind 11 (this is dropping .. the largest turbines in the North Sea are more like 9)
onshore wind 12 (for well-sited large turbines)
There are no silver bullets if you want to reduce carbon emissions, but there are many choices that are much better than fossil fuels.
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