AuroraGlacialis
04-15-2011, 10:12 AM
http://cultureofinsanity.blogspot.com/2011/04/algaeworld-die-algenwelt.html
http://www.avatar-forums.com/images/imported/2011/04/47.jpg
The researchers found that 21 billion gallons of algal oil, equal to the 2022 advanced biofuels goal set out by the Energy Independence and Security Act, can be produced with American-grown algae. That's 17 percent of the petroleum that the U.S. imported in 2008 for transportation fuels, and it could be grown on land roughly the size of South Carolina. But the authors also found that 350 gallons of water per gallon of oil -- or a quarter of what the country currently uses for irrigated agriculture -- would be needed to produce that much algal biofuel.
Whew - amazing 17% of the petroleum "needed" and all it takes is an increase in water use by another 1/4, and covering a whole US state (albeit a smaller one) with algal farms...To be fair, the also try to work with wastewater and oceanwater to lessen the impact and actually find a proper use for wastewater, but there are no numbers yet on how much that can provide.
But evaporating water is a potent greenhouse gas - no matter where the water came from. And also the "spent" water has to go somewhere - it potentially is salty due to the evaporation and may contain additives used for growing these algal monocrops. Oh and of course they will want to use GMO algae and large scale nanotechnology for that. They do not mention how much energy is needed to keep the pumps running and cleaning the ponds and all that - this may reduce the energy gain...
Looks like at least land-based, open pond algal biofuels are not really a solution to anything. Other models include closed ponds, tubes (very expensive) or ocean based (giant floats) systems, but given the size of this, these seem less feasible - economically and technically.
http://www.avatar-forums.com/images/imported/2011/04/47.jpg
The researchers found that 21 billion gallons of algal oil, equal to the 2022 advanced biofuels goal set out by the Energy Independence and Security Act, can be produced with American-grown algae. That's 17 percent of the petroleum that the U.S. imported in 2008 for transportation fuels, and it could be grown on land roughly the size of South Carolina. But the authors also found that 350 gallons of water per gallon of oil -- or a quarter of what the country currently uses for irrigated agriculture -- would be needed to produce that much algal biofuel.
Whew - amazing 17% of the petroleum "needed" and all it takes is an increase in water use by another 1/4, and covering a whole US state (albeit a smaller one) with algal farms...To be fair, the also try to work with wastewater and oceanwater to lessen the impact and actually find a proper use for wastewater, but there are no numbers yet on how much that can provide.
But evaporating water is a potent greenhouse gas - no matter where the water came from. And also the "spent" water has to go somewhere - it potentially is salty due to the evaporation and may contain additives used for growing these algal monocrops. Oh and of course they will want to use GMO algae and large scale nanotechnology for that. They do not mention how much energy is needed to keep the pumps running and cleaning the ponds and all that - this may reduce the energy gain...
Looks like at least land-based, open pond algal biofuels are not really a solution to anything. Other models include closed ponds, tubes (very expensive) or ocean based (giant floats) systems, but given the size of this, these seem less feasible - economically and technically.