Opening of CO2 to Methanol plant at Svartsengi geothermal plant | Think GeoEnergy - Geothermal Energy News C02 to methanol? I'd never heard of this! I doubt the process is any kind of silver bullet that'll replace gas/diesel, or that the profit margain is anywhere close enough that exxon will swoop in and buy up the rights, but still ... who knew! .
That is a very large power cost (40,000 MWh per year) to produce a fairly small amount of methanol to be blended with gasoline (5 million liters per year or about 1.2 million gallons?). However, since they are using clean power which Iceland has heaps and gobs of, taking 5 tons of CO2 out of the air is vastly superior to not.
You nailed it. The energy value of 1.2M gallons of methanol is about 19 MWH. This can make sense where the power couldn't directly be used to displace fossil fuels. Otherwise, you might get a better return just using the power. They eliminate 5000 tons CO2, using 40,000 MWH. On the Virginia electrical grid, displacing 40,000 MWH with carbon-free energy would eliminate about 22,000 tons of new CO2 emissions. You can also do this with (e.g.) a solar furnace. Sandia's Sunshine to Petrol project to chemically transform carbon dioxide into carbon-neutral liquid fuels - December 5, 2007
Getting CO2 back to CH4 will always take a lot of energy. Certainly doable, but maybe a lot like electrolyzing water to make hydrogen.
energy is not a constrained resource, getting it collected and transported to where you need it for work is the constraint.
At 1st - the parallel sickened me. THEN - I remembered (as just mentioned one post up) that it's really NOT like hydrogen. Unlike methane, hydrogen has much worse requirements in order to use it as fuel - some examples that pop into mind.... High cost to compress, or High cost to refrigerate High cost for an auto fuel stack (needs regular replacing) High cost for embrittlemebt resisting plumbing etc All that to say methanol is.apparently worlds more practical than hydrogen ... even when the methanol sequestrated is from c02. SGH-I717R ? 2
...today nat gas is used to make H2 as well as methanol. When you are making methanol it's OK if you have some CO2 in the nat gas, some goes to methanol. The article says they got H2 + CO2 so then- Water gas shift is H2 + CO2 <---> CO + H2O so one can play around to get what you need in a reactor. Does suggest if you are going to build a methanol plant, you could take in extra CO2 if you are not already taking in the max. I don't know if they generally max out CO2.