Tuesday, March 01, 2011

We're Saved!! (or not)

(And yes, I'm blogging from work which should tell you everything you need to know about how busy it is so far this week.)

A Massachusetts company claims it can make diesel fuel directly from a genetically-engineered cyanobacterium:

Joule Unlimited has invented a genetically-engineered organism that it says simply secretes diesel fuel or ethanol wherever it finds sunlight, water and carbon dioxide.

...Joule claims, for instance, that its cyanobacterium can produce 15,000 gallons of diesel full per acre annually, over four times more than the most efficient algal process for making fuel. And they say they can do it at $30 a barrel.

And when anyone questions the genius behind these, um, extravagant claims, to be polite about it?

Sims said he knows "there's always skeptics for breakthrough technologies."

"And they can ride home on their horse and use their abacus to calculate their checkbook balance," he said.

Yes, being a horse's ass is the hallmark of breakthrough science. So lets blow the dust off our abacus and do the math that Sims isn't capable of.

Fuel consumption for over-the-road travel (buses, trucks and automobiles) is around 174,930,000,000 gallons per year as of 2006. That was certainly kicked down by the current recession, but we all know the economy is going to bounce back any day now, which makes it good enough for our back-of-the-envelope abacus work. At 15,000 gallons per acre, that's 11,662,000 acres of algae. Double that for tankage, plumbing, maintenance roads, processing facilities, and everything else that you would need to make this work and we're up to 23,324,000 acres or 36,444 square miles. That's more-or-less the state of Indiana, if you're interested. Or 30% of the state of New Mexico is more likely because solar insolation is greater there.

Speaking of insolation, the sunniest place in North America (El Paso, TX) receives a maximum of 7.42 KWH/sq meter/day or 2,708 KWH/sq meter/year. 15,000 gallons of diesel per acre comes to 3.71 gallons of diesel per sq meter. At 40.7 KWH/gallon for diesel fuel, that means a net harvest of 151 KWH/sq meter or 5.6% of the maximum available sunlight. That doesn't sound too bad until you consider that a) that's using the maximum sunlight at the spot in North America with the maximum solar insolation, and b) photosynthesis is only between 3% and 6% efficient in naturally-occurring plants. We are supposed to believe that this genetically-engineered cyanobacteria can support itself and reproduce, and still be able to convert 5.6% of the maximum available sunlight into pure diesel fuel? I don't need to step in it to know bullshit when I see it.

Another problem: the fragility of engineered organisms. In spite of the media hype about Killer Korn from Outer Space (well, OK; Monsanto, which to media douche nozzles is about same thing), most engineered organisms must be carefully protected in a lab to survive. What happens to this Wonder Bacterium when real cyanobacteria start growing in the tanks? At the very least, it's going to kick that 15,000-gallons-per-acre production right where it hurts.

And another problem: What happens to that 15,000 gallons of diesel per acre when an entire ecosystem takes over the tanks? At the scale we're talking about here, there is absolutely no way to prevent that. There are plenty of microorganisms that would love to munch on those long-chain hydrocarbons we are trying to produced. Not to mention an entire biology textbook worth of organisms that would love to munch on our precious cyanobacterium (and each other, and still others that munch them and so on and so forth). Nature has a nasty habit of mopping up spare energy left lying about; ask a backyard gardener about the endless parade of critters from the microscopic to bears that constantly assault their veggies.

Looming over all of this: Net energy. How much energy is it going to take to build out and maintain the infrastructure for 35,000+ square miles of tanks and plumbing? How much energy to pump all that liquid around? How much energy to extract the diesel and get it into usable form? In other words, could you run the entire operation on the diesel fuel being produced and have any left over to sell?

I wish the scientists at Joule Unlimited all the luck in the world. It would be nice if this would work, even at triple the projected cost. But I'm keeping my horse and my abacus. Just in case.

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