3 ms·

As in many times more solar panels than can be constructed with all of the resources that can possibly ever be extracted from the earth? I suppose that is true,

As in many times more solar panels than can be constructed with all of the resources that can possibly ever be extracted from the earth? I suppose that is true, and an be verified with some pretty simple back of the envelope calculations. I must admit, I only skimmed through the apparently meaningless technobabble, but if someone could let me know succinctly, we still don't have anything more effective at carbon sequestration that trees, right? And how well are trees doing?

hedora 4y ago
Capturing a gallon of gasoline CO2 emissions from the atmosphere would cost about a dollar at scale. (1 gallon -> 20lbs CO2. Technologies advertising $100/ton of CO2 are somewhat common these days. A ton is 2000lbs, so $100 / ton CO2 implies $1 per gallon of gasoline). There are many technologies that could achieve this, but I don’t think this article is describing one of them. They want to convert CO2 and water to natural gas and have roughly 30% energy efficiency. A gallon of gas contains 33kWh, so (handwave gasoline == natural gas), it costs 100kWh per gallon equivalent. A kilowatt hour is at least $0.10, so > $10 per gallon-captured-ish. If the carbon intensity of natural gas is similar to gasoline, so the computation is close enough and the technology in the article is about 10x off state of the art. On the bright side, the article’s technology would “only” require 5% of the earth’s surface be covered in solar panels, so state of the art would need 0.5%, which is feasible, in terms of land use, at least. Carbon intensity table: https://www.forestresearch.gov.uk/tools-and-resources/fthr/biomass-energy-resources/reference-biomass/facts-figures/carbon-emissions-of-different-fuels/ https://www.forestresearch.gov.uk/tools-and-resources/fthr/b...

3 ms·

As in many times more solar panels than can be constructed with all of the resources that can possibly ever be extracted from the earth? I suppose that is true,

by scaramanga 4y ago

hedora 4y ago
Capturing a gallon of gasoline CO2 emissions from the atmosphere would cost about a dollar at scale. (1 gallon -> 20lbs CO2. Technologies advertising $100/ton of CO2 are somewhat common these days. A ton is 2000lbs, so $100 / ton CO2 implies $1 per gallon of gasoline). There are many technologies that could achieve this, but I don’t think this article is describing one of them. They want to convert CO2 and water to natural gas and have roughly 30% energy efficiency. A gallon of gas contains 33kWh, so (handwave gasoline == natural gas), it costs 100kWh per gallon equivalent. A kilowatt hour is at least $0.10, so > $10 per gallon-captured-ish. If the carbon intensity of natural gas is similar to gasoline, so the computation is close enough and the technology in the article is about 10x off state of the art. On the bright side, the article’s technology would “only” require 5% of the earth’s surface be covered in solar panels, so state of the art would need 0.5%, which is feasible, in terms of land use, at least. Carbon intensity table: https://www.forestresearch.gov.uk/tools-and-resources/fthr/biomass-energy-resources/reference-biomass/facts-figures/carbon-emissions-of-different-fuels/ https://www.forestresearch.gov.uk/tools-and-resources/fthr/b...