The Algae Attraction - Regarding article that states "Clean coal is an imperative. Some breakthrough technologies to achieve that goal now exist while others are years away. One such concept is to use waste carbon emissions from power plants to grow algae, which is subsequently converted to energy and because those releases would re-cycled, carbon dioxide emissions would be cut in half. "

Step back and look at algae to capture CO2 emissions. There are 4 logic problems:

1. It will not be 100% effective; some percentage of the CO2 will not be captured, so we are looking at the potential to reduce, but not stop CO2 emissions from coal.

2. This is not sequestration, it is recycling. When the algae is burned, whether in a power plant or in an organism, it will again release its CO2. That delays the release of CO2, but we will end up with just as much CO2 in the atmosphere eventually, UNLESS the amount of coal being mined and burned is cut in half, and I don't think that is the intent of the R&D sponsors.

3. Parasitic loads for pumps and blowers, plus the capital and maintenance costs of the algae farm, plus makeup water for the huge evaporative losses, plus fertilizer for the algae, will further burden the economics and the power output.

4. Algae converts CO2 to plant sugars and cellulose by photosynthesis. Exposing all the algae to that much sunlight will require a very large land area. Photosynthesis efficiency is about 12%. The plant efficiency would be around 40%. Combined efficiency would be 4.8%. Solar PV efficiency is nominally 16%. So converting the same land area to solar PV would produce roughly 3 times as much electricity. New thin-film solar collectors now being produced at prices competitive with coal-fired generation

These 4 logic problems combine to show that the algae scheme will produce LESS electricity, MORE CO2, and lower return on investment. Think outside the box, but put the algae scheme back in the box and bury it.