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I read the article wondering why you'd want to do this by sucking in air when you could do it with exhaust from gas-powered power plants that is much richer in

I read the article wondering why you'd want to do this by sucking in air when you could do it with exhaust from gas-powered power plants that is much richer in CO2 than regular air. In fact, there was coverage the other day of a new gas-fired power plant that throws off CO2 for storage in oil wells. Why not use that CO2? https://www.vox.com/energy-and-environment/2018/6/1/17416444/net-power-natural-gas-carbon-air-pollution-allam-cycle https://www.vox.com/energy-and-environment/2018/6/1/17416444...

thinkcontext 8y ago
Exactly, that new plant design is a much bigger deal. It gives you the CO2 for "free" as part of its normal operation without a power penalty. This article tries to make a point about how if the gasoline is made from CO2 from the air, it makes burning it carbon neutral. This is true but it misses the point. You want to get the most CO2 reduction for your money, so do the cheapest carbon capture first. Its cheaper to collect it from large point sources, so do that first. Once those emissions are being captured or simply ended from the plant retiring then move on to more expensive DAC.
notabee 8y ago
The reason is simple: we've already put enough CO2 into the atmosphere to cause adverse changes over a long period of time. A lot of the IPCC models and their discussion centers around more near-term climate threats over the next 100 years or so caused by continued emissions and overall severity of going ever more "over budget" with CO2 levels, but we're still 100+ ppm of CO2 over the highest average of the last half a million years or more. That CO2 is going to hang around in the atmosphere for quite some time as the natural processes like weathering that lower it are slow, and its presence will add extra heat from solar radiation while it's still there. If we suddenly stopping emitting now, we would still be above baseline but not in the apocalyptic range. If things don't change quickly though, we're going to have to suck CO2 from the atmosphere one way or another because just halting emissions won't be enough.

thinkcontext 8y ago

Exactly, that new plant design is a much bigger deal. It gives you the CO2 for "free" as part of its normal operation without a power penalty. This article tries to make a point about how if the gasoline is made from CO2 from the air, it makes burning it carbon neutral. This is true but it misses the point. You want to get the most CO2 reduction for your money, so do the cheapest carbon capture first. Its cheaper to collect it from large point sources, so do that first. Once those emissions are being captured or simply ended from the plant retiring then move on to more expensive DAC.

notabee 8y ago

The reason is simple: we've already put enough CO2 into the atmosphere to cause adverse changes over a long period of time. A lot of the IPCC models and their discussion centers around more near-term climate threats over the next 100 years or so caused by continued emissions and overall severity of going ever more "over budget" with CO2 levels, but we're still 100+ ppm of CO2 over the highest average of the last half a million years or more. That CO2 is going to hang around in the atmosphere for quite some time as the natural processes like weathering that lower it are slow, and its presence will add extra heat from solar radiation while it's still there. If we suddenly stopping emitting now, we would still be above baseline but not in the apocalyptic range. If things don't change quickly though, we're going to have to suck CO2 from the atmosphere one way or another because just halting emissions won't be enough.