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Novel Algae Fuel-Farming Method Gets Big Backing
Al writes "Dow Chemical has given its backing to a Florida startup called Algenol Biofuels that hopes to produce commercial quantities of ethanol directly from algae without the need for fresh water or agricultural lands. Dozens of companies are trying to produce biofuels from algae, mostly by growing and harvesting the microorganisms to extract their oil. Algenol has chosen instead to genetically enhance certain strains of blue-green algae, also known as cyanobacteria, to convert as much carbon dioxide as possible into ethanol using a process that doesn't require harvesting to collect the fuel. Algenol's bioreactors are troughs covered by a dome of semitransparent film and filled with salt water that has been pumped in straight from the ocean. The photosynthetic algae growing inside are exposed to sunlight and fed a stream of carbon dioxide from Dow's chemical production units. The goal is to produce 100,000 gallons of ethanol annually."
And here I thought this was going to be about Exxon backing Synthetic Genomics. http://www.nytimes.com/2009/07/14/business/energy-environment/14fuel.html Algae fuels are just so hot right now!
Nothing quite so exotic- the salt is going to end up a toxic byproduct of this process. The rest is just solar-based distillation- salt water + algae + sun -> fresh water + ethanol, which is then further distilled down into it's component parts.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
You should have read TFA. Sometimes there are more details in it.
The salt water isn't pumped out. The alcohol evaporates into the air at the top of the bioreactor and is skimmed off. The bioreactor does produce fresh water as a "waste product" but presumably they seem rather optimistic about finding a better use for that than dumping it in the ocean.
For reference that would require the entire east coast be filled to ~55 miles inland.
Ever driven across the central part of the US? There's lots of corn... 87 million acres, or about 136,000 square miles, actually. Now, I know not all of that corn is used for ethanol production. However, there are large swaths of land in the US within reasonable distance of an ocean which aren't much use beyond growing pine for timber (like coastal areas of North Carolina or Texas) because they're not suited for growing other crops. This could be a much more efficient use for such land.
Plus, not all of that 24 acres is actually producing ethanol. We're talking 3100 tanks that take up 250 square feet each, or about 17.79 acres. As this technology matures and as farms are scaled up, you'll likely see increased output per acre.