Waste CO2 shows 'closed loop' supply potential for National Grid
Waste carbon emissions could be harvested to generate significants amounts of electricity through an old-fashioned laboratory treatment method, Dutch scientists have claimed.
By pumping the carbon dioxide emitted by power stations through water or other liquids, this would produce a flow of electrons to produce electricity, enough to create 1,750 terawatt hours annually, according to a research paper published in the journal, Environmental Science & Technology Letters.
The electrolysis method potentially offers an energy-from-waste solution where the exhaust from one cycle of electricity production could be used immediately to deliver another flow of power to the grid.
Scientists from Wetsus, a centre for water excellence in the Netherlands, and Wageningen University used porous electrodes and flushed carbon dioxide into water to get their flow of current.
In their experiment, they found that as they flushed their aqueous electrolyte with air, and alternately with CO2, a supply of electricity began to build up. Since the air that comes from the chimneys of fossil fuel-burning power stations contains anything up to 20% of CO2, even the emissions represent a potential for more power.
They discovered they could get even more power if instead of a water solution they used an electrolyte of monoethanolamine. In experiments, this delivered an energy density of 4.5 mW a square metre.
Ironically, this electrical energy is already potentially available at the top of the power chimney stacks because on release, one 'solution' of greenhouse gas in air immediately mixes with a different-strength solution in the air.
The scientists admit it would require huge investment and a great deal of engineering ingenuity to convert greenhouse emissions into electricity in a cost-effective way.