The Environment

BigRedBuster said:
This is cool. 
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Articles like this restore a lot of hope that humans are more than capable of overcoming our problems.  Hopefully, this technology is as successful as the article makes it sound and we can curb a lot of problems before they start.

But to temper my expectations, the world adds around 35-40 BILLION metric tons of CO2 each year.  I don't know the volume these sites are capable of, but that is a lot of carbon dioxide.

 
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funhusker said:
Articles like this restore a lot of hope that humans are more than capable of overcoming our problems.  Hopefully, this technology is as successful as the article makes it sound and we can curb a lot of problems before they start.

But to temper my expectations, the world adds around 35-40 BILLION metric tons of CO2 each year.  I don't know the volume these sites are capable of, but that is a lot of carbon dioxide.
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And from the article, what they've done is reduce the cost of CO2 atmospheric extraction from about $600/ton to $100/ton. Just to offset the world's current annual CO2 emissions would cost about $3.5-4 TRILLION (with a T) per year. Plus it's converting that CO2 into jet fuel, which we either have to store somewhere or, more likely, use so that the CO2 goes right back into the atmosphere.

Something like this might be useful right at the exhaust of a fossil fuel-burning power plant as an intermediate solution (to reduce the rate at which fossil fuels are burned), but ultimately if we're going to reduce greenhouse gases it's going to have to come from not burning fossil fuels. Then carbon sequestration methods (most likely to be on big enough scale will be growing trees) can make an impact.

EDIT: Here's a direct link to the journal paper: https://www.cell.com/joule/pdfExtended/S2542-4351(18)30225-3

 
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RedDenver said:
And from the article, what they've done is reduce the cost of CO2 atmospheric extraction from about $600/ton to $100/ton. Just to offset the world's current annual CO2 emissions would cost about $3.5-4 TRILLION (with a T) per year. Plus it's converting that CO2 into jet fuel, which we either have to store somewhere or, more likely, use so that the CO2 goes right back into the atmosphere.

Something like this might be useful right at the exhaust of a fossil fuel-burning power plant as an intermediate solution, but ultimately if we're going to reduce greenhouse gases it's going to have to come from not burning fossil fuels. Then carbon sequestration methods (most likely to be on big enough scale will be growing trees) can make an impact.
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Let's think bigger than this.

Let's say the technology is developed enough that all new cars have this in their exhaust systems.  The fuel is then put right back into your tank.  You would still fill up at the pump.  But, all CO2 would never leave the exhaust.

What if we did the same thing to power plants?  All exhaust from the power plant would go directly through this system.  The fuel that is produced, then goes into the fuel supply.  Then into cars that also have these systems in their exhaust....like mentioned before.

You take out car and power plant exhaust and you have taken out a huge amount of the problem.

 
BigRedBuster said:
Let's think bigger than this.

Let's say the technology is developed enough that all new cars have this in their exhaust systems.  The fuel is then put right back into your tank.  You would still fill up at the pump.  But, all CO2 would never leave the exhaust.

What if we did the same thing to power plants?  All exhaust from the power plant would go directly through this system.  The fuel that is produced, then goes into the fuel supply.  Then into cars that also have these systems in their exhaust....like mentioned before.

You take out car and power plant exhaust and you have taken out a huge amount of the problem.
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No, that's a perpetual motion machine. The process of convert the CO2 into other forms takes energy. In the paper they propose using this technique at large solar or wind energy facilities.

For a power plant, it's way more efficient just to use the energy from the solar or wind than going through fuel->CO2+energy->fuel

 
RedDenver said:
No, that's a perpetual motion machine. The process of convert the CO2 into other forms takes energy. In the paper they propose using this technique at large solar or wind energy facilities.

For a power plant, it's way more efficient just to use the energy from the solar or wind than going through fuel->CO2+energy->fuel
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I'm thinking beyond what the article discussed.

I'm all for renewable fuel sources.  However, I believe they won't completely replace fossil fuels.  So, you build those up as much as possible.  Then, if you can use this technology to convert the CO2 that is being produced into fuel.....win win.

When the first computer was built and took an entire building to house it, nobody dreamt that we would all be carrying around a computer a million times more powerful in our pockets.

 
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I read the paper, and this process is less impressive than the news article makes it seem. First, the process requires burning natural gas for producing enough heat for the process steam required. That's not ideal but the carbon from the natural gas is also captured, so it's still net CO2 reducing. Second, even using electricity doesn't eliminate NG but does reduce NG consumption from 8.81 GJ to 5.25 GJ (60% reduction) per ton of CO2 capture (and requires 366 kWh of electricity). If that electricity comes from renewable sources, then that's much better than if it comes from the grid where CO2 emissions offset some of the capture depending on the mix of power sources for the grid in that region. Third, the process outputs high pressure CO2, which then has to be used or stored in some way. The paper loosely describes concepts for using electrolysis to produce O2 (already used in the CO2 capture process, so electrolysis gets rid of another process) and H2, which can be used to create fuels from the compressed CO2. But there isn't a detailed description of that process and what it costs or what other inputs it requires. Finally, the process requires 4.7 tons of pure water per ton of CO2 capture, which could be a major problem especially in the arid parts of the world (like the entire western half of the continental US).

While this may be a cost effective way to remove CO2 from the atmosphere, I'm not sure the natural gas and water consumption makes sense environmentally. Plus the output CO2 still has to be dealt with since we can't just stick in big tanks and turning it into fuels hasn't yet gotten past the drawing board. Also, turning it into fuels and then burning those means we're actually adding CO2 to the atmosphere, not removing it, because of the NG used in the capture process.

 
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TGHusker said:
Nature has a way of helping itself as noted in this article

https://www.axios.com/west-antarctica-rising-could-halt-melting-glaciers-325bec72-e20e-47d1-bb5f-2e1d2f9f4857.html
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However:

Antarctic ice melting faster than ever, studies show
Rate of melt has accelerated threefold in last five years and could contribute 25cm to sea-level rises without urgent action

A separate study warns that unless urgent action is taken in the next decade the melting ice could contribute more than 25cm to a total global sea level rise of more than a metre by 2070. This could lead eventually to the collapse of the entire west Antarctic ice sheet, and around 3.5m of sea-level rise.
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