Nowhere in the world is CCS taking place from a commercial coal-fired power plant. A few projects are disposing of CO2 by pumping it underground, but on a very small scale and in highly specialized operations using very concentrated CO2. There is one demonstration plant in Australia and a three or four commercial plants in the US, Canada and Norway but they all extract CO2 from natural gas sources or from coal gasification.
Surprisingly, Wikipedia has a good summary of the state-of-the-art in CCS, mainly derived from an IPCC 2006 report.
The process of CCS is bewilderingly complex and vastly expensive. First, carbon dioxide must be extracted from waste gas (e.g. by bubbling it through chemical solutions or burning the coal in oxygen then cooling the exhaust gas into water and CO2), then transported to the disposal site (e.g. liquidized, by tanker) then pumped underground (e.g. by pipeline into undersea caverns).
In other words, an entire new industry must be created from nothing – with none of the technology already established, none of the infrastructure already existing and none of the safety or suitability of the disposal sites proven. A major concern with undersea disposal is that the CO2 can escape, causing ocean acidification and major destruction of the aquatic ecosystem.
CCS is so far from being practically possible that it is utterly senseless to expect it to make any contribution to CO2 reduction before 2030. CCS is, essentially, a ruse to avoid the obvious – a new generation of nuclear power plants. The cost of CCS will dwarf that of nuclear power.
The attention of the scientists who wrote to the Observer would be better directed to nuclear power and to technologies that really have a chance of lowering CO2 emissions, like genetically modified algae.
For a tiny proportion of the cost of one CCS demonstration project, existing experiments with GM algae could be scaled up to provide both CO2 reduction and a cheap source of food. GM algae can gobble up huge quantities of CO2 and convert it into hydrocarbons or protein – instead of wasting it under the sea floor.
Two good reports of work being done with GM algae:
http://www.theengineer.co.uk/Articles/307109/Late+bloomer.htm
http://epmb.berkeley.edu/facPage/dispFP.php?I=25
{ 0 komentar... Views All / Send Comment! }
Posting Komentar