No. of Recommendations: 14
Three questions, for anyone who can enlighten me about this idea.
With trepidation I attempt simple answers to DTB's complex questions.
1. What do they plan to do with the CO2 they capture?
Right now, it is to sequester it underground in formations where it won't be released again in the future. Deep saline reservoirs are one primary target. Old oil field are another, but they run the risk of old oil wells not being properly sealed off. The key will be how trustworthy those disposing of the CO2 may be judged.
There are possible alternate uses from EOR to as raw materials for both building materials or low carbon fuels. But these are at very early stages. EOR is proven, but the cost of CO2 recovery must be balanced against the current costs of CO2 from natural sources.
2. If it is sequestering the carbon underground, wouldn't it make more sense to just use the smokestack emissions of a big natural gas power plant, where CO2 is a high percentage of (say 50%) as opposed to ambient air that has a concentration of about 0.04% CO2?
Smokestack emissions are a mixture of CO2 emissions with nitrogen gases and other combustion products. The concentrations are much lower than 50%, and sequestering them is a far different animal than just CO2. CO2 dissolves, and can be compressed to a liquid. The other components don't. So the CO2 must be separated.
You're right about concentration mattering in cost. The highest concentration sources now are from ethanol production and ammonia production. So these will be immediate targets followed by emissions from cement plants, power plants, and industrial plants such as refineries and petrochemical plants. DAC will, by an order of magnitude, be more difficult. It's the "Holy Grail" aspiration. Yet people are working on it.
3. If XOM gets the cost down to $100 per ton of CO2, this means about $100 to recapture the CO2 released by burning 3.15 barrels of oil, so it would add about $100/3.15=$33 to each barrel of oil burned. I can see how the economics of this might work, if we had vast amounts of cheap renewable power that we couldn't use off peak (wind at night, for instance.) Is that cheap off-peak wind/solar power already priced in to the $100/ton target?
Coping with CO2 emissions isn't simply an issue of the cost of generating electricity. Many critical products to modern civilization can't be derived from electricity. These include transportation fuels for airlines, heavy transport (at present) etc., fertilizer for food, cement, steel, plastics, lubricants, synthetic clothing (circa 70% of supply) pharmaceuticals, and many other uses. We have to have O&G to produce these. So we must find a way to reduce their emissions. And, yes, society will have to pay a higher cost for products derived from O&G if they wish a lower carbon future. This can be done, but it won't come free. We'll all have to pay our parts, either directly, or via repaying government debts. There's no magic answer to reducing carbon emissions.
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These are short answers to key questions. But I think they're basically on target. Others may disagree.
