Carbon capture and storage (CCS) is one of the holy grails to combat climate change. (Cheap utility-scale electric storage is another. Cheap and safe small-scale nuclear is the third.) In theory, it sounds easy. Take the exhaust from a big fossil fuel plant, extract the CO2, and send the CO2 somewhere besides the air.
The obvious rub is: where do you send the CO2? Fortunately, there are answers. CO2, for example, is useful in the secondary recovery of liquid hydrocarbons. (It can also be used for natural gas.) So you can site CCS-equipped coal plants near old oil fields and sell them the CO2.
So the Mississippi Power Company decided to build a CCS-equipped coal plant near some older oil fields in the state. Ignore, for the moment, whether anyone wants to try to extract oil from old Mississippi wells at current prices; you can still always pump the CO2 underground regardless.
Well, Mississippi Power just announced another $142 million overrun on the project, taking the cost up to $6.6 billion from a projected $2.9 billion. With a capacity of 582 MW, this may well be the most expensive power plant in the world. The recent overruns were due to problems with the coal gasifier unit which turns soft lignite into natural gas (well, synthetic natural gas, which sounds oxymoronic) and extracts carbon dioxide. Earlier problems had to do with linings on the tubes carrying gas heated to 1800 degrees. And before that they just plain underestimated the amount of tubing needed and the cost of installing it. A 2013 filing blamed overruns on “abnormally wet weather and lower-than-planned construction labor productivity.”
Nuclear power has not overcome similar problems.
So I would not bet on CCS to save us.