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jessriedel

Pounds of CO2 emitted per million British thermal units (Btu) of energy for various fuels:

Coal 228.6 - 205.7

Diesel fuel and heating oil 161.3

Gasoline 157.2

Propane 139.0

Natural gas 117.0

https://www.eia.gov/tools/faqs/faq.cfm?id=73&t=11

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Does this include the CO2 emitted in the process of extracting and refining diesel/gasoline? Depending on the source of the oil (Canadian Tar sands vs Saudi Arabia), its carbon footprint can vary drastically.

All of the fuels listed in the grandparent have extracting and refining costs which depend on the source.

That is true - but I believe that extraction and refining is a much bigger contributor to oil's footprint, compared to coal's. It is also far more variable.

To turn a barrel of tar sands oil into gasoline, for example, adds another ~230 pounds of CO2 to the atmosphere - in addition to the emissions from burning it. That's ~40 pounds/million BTU.

It almost costs us more energy to mine and refine tar sands oil, then we get out of burning it.

Looks good for the future of Methane Hydrate, of which undersea deposits could provide 6 centuries of power for our planet. Methane Hydrate is natural gas in a frozen water matrix.

Should those deposits start to outgas (?), due to warming oceans, we'll have to aggressively, proactively burn that methane.

Interesting idea. But its cold down there; take a lot of warming to have that problem?

Theoretically, meteor strikes may have exposed/breached a deposit sometime in history. So large releases probably happen from time to time. How would we know? What trace would these catastrophic methane releases leave in the geologic record?

...and nuclear is 0?

Almost.. the IEA puts it at 2-59 grams per kwh. Hydro at 2-49g; wind at 7-124g; and solar at 13-731g. In comparison to nat gas at 389-511g.

Hydro and nuclear are pretty much tied. And wind is a close 3rd.

see page 134: also has SO2, NOX, and a few other stats: http://www.oecd-nea.org/ndd/reports/2002/nea3676-externaliti...

Solar's at 13-731g is due to mixing a wide range of technology and calling it 'solar'. Solar thermal power plants are simply terrible designs that never really improved over time, and often include natural gas for nighttime operation.

So, in terms of installed capacity it's much closer to 13 and generally below nuclear.

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