Startup Claims to Make $1/Gallon Ethanol

gnick writes to mention Wired is reporting that an Illinois startup is claiming they can make ethanol from most any organic material for around $1/gallon. Coskata, backed by General Motors and several other investors, uses a process that is bacteria based instead of some of the other available methods. The bacteria processes organic material that is fed into the reactor and secretes ethanol as a waste product.

Comments

Need to make Butanol, not Ethanol

[Nick Driver]

Ethanol has about 84K BTU/gallon of energy for use in a piston engine. Butanol has about 110K BTU/gallon, compared to an average of 115K BTU/gallon for unleaded gasoline. Butanol also does not absorb water out of the air like ethanol does readily. Butanol can be made by via bacteria fermentation of biomass similar to like ethanol can. Butanol does have a problem with not vaporizing good enough for cold starts in very low temperatures, but that could be overcome with electric heater incorporated in a vehicle's fuel injector system for operation in cold weather.

Re:logic

[Martin Blank]

How many acres are we going to have to devote to ethanol feedstock to supplant oil?

That depends on the feedstock. We can never do it with corn, as the math just doesn't bear out. Consider the following, based on the recently-published Crop Production 2007 Summary:

Planted area: 93.6 million acres
Average yield: 151.1 bushels per acre
Total production: 14.1 billion bushels

Ethanol production from corn usually nets about 9.5 liters of ethanol per bushel. A conversion of all of the corn to ethanol would net about 134 billion liters of ethanol. Ethanol has an energy density of 24 MJ/L, and gasoline's is 34.6 MJ/L, so E85 would come in at about 25.6 MJ/L. Daily average gasoline consumption in the US is about 1.47 billion liters per day, or about 50.9 billion MJ. To match that with E85 would require 1.99 billion liters of E85, which would require 1.69 billion liters of ethanol. Unfortunately, converting all of the corn production to ethanol would allow only 79 days of consumption of E85 at current energy use rates.

It's an extreme, unrealistic calculation, as we could never do a complete conversion, and it doesn't factor in energy used for the planting, care, or harvest. But it does help to drive home the point that it's infeasible to use standard plants for ethanol production. Even switching to sugarcane or sugarbeets isn't going to help because of the massive acreage required. The only mechanisms that will be able to reliably replace our reliance on fossil fuels are those that are able to take advantage of volume of organic materials, including excretion methods such as algae and bacteria, and possibly methods such as cellulosic conversion and thermal depolymerization (if they work out profitably).

Re:What! GM backing cheap fuel!

[jawtheshark]

with cars lasting longer these days, people will sell their old one just because the new one gets like double the gas mileage

Which would be a quite dumb thing to do. Okay, it depends a bit on the car and how long your commute is per day. Let's see an example:

• I have an 8 year old car which does 10l/100km (23.5mpg), and as such it's a gas guzzler for European standards. It still is in prime condition though.
• I do 15000km per year (9320miles)
• My current car, new cost 35000€ (± 51000$)in 2000, and is currently valued about 10000€ (± 14500$) on the second hand market.
• A new, smaller, more fuel efficient car, like the one my wife has, does 5l/100km(47mpg)
• My wifes car cost 23000€ (± 33500$) in 2006.
• Gas currently costs 1.2€/l (6.66USD/gallon). While one car uses less gas, the prices will soar in the same way and as such the evolution of said price doesn't really matter. It shortens the final calculation, which I admit.
• One gas tank in both cars is 50l (13.2gallon). Coupled with the above information, one gas tank costs 60€ (88$)

Now look what happens: I sell my car for 10000€, and buy a new fuel efficient one for 23000€. I now have 13000€ spend, that I have to justify with future gas savings. That's the equivalent of 13000/60 = 217 fill ups! The equivalent of 217*50 = 10850 litres, which means I can drive 108500km with my old car, or 217000km with my new car. That's the equivalent of a bit more than 7 years for the old car and 14 years for the new car. Now look at those figures! In 7 years, my car will be 15 years old and have no value (10 years later it will be a vintage car though) That's a very long time to recoup costs.

Anyone saying the buy a new car "because it has better mileage" should first do this small calculation. If the cost is not recouped in a short time (which means you drive a lot), then it simply is not worth it. Sure, you might have other reasons, but "saving money" is not a valid one.