Slashdot Mirror
Ethanol Not A Total Loss
blamanj writes "It has been argued that using corn-derived ethanol as a fuel costs more in energy than what is produced. However, it is being reported that a new study that calculates the energies to include processing by-products reports a net gain in energy such that every BTU of existing liquid (fossil) fuels spent produces a 6 BTU return. While this doesn't address the environmental impact of large-scale farming, it's good news for Iowa farmers."
Using EtOH does a couple things, each of them are laudable, IMHO:
- Creates another market for Corn. By opening another market, we might reduce farm subsidies.
- Reduces dependence on foreign oil and reduces the need to use reserves.
- Reduces air pollution. Specifically it reduces ozone production. That's why EtOH is used as an oxygenator during the summer months.
- Finally, growing lots of corn improves the carbon equation. Instead of pumping up 50 million year old carbon that has been sequestered all this time, using ethanol helps make it more of a zero sum game. Ideally, you're growing (removing) the same amount of carbon from the atmosphere that you're burning as EtOH. At least that's the theory.
In short, EtOH isn't a magic bullet, but it's definitely part of the mix.My father is a blogger.
Ultimately, we're talking about solar energy here. A plant uses photosynthesis in pulling CO2 out of the air, releasing the O2 while constructing more useful molecules out of the carbon. We then use some energy of our own to process this plant and the solar-generated molecules into a form where we can release the energy.
So it's not surprising that if you leave out the sun, your equations will indicate that we're creating energy out of nothing.
Reading through the report, I see that in every phase of production a different fuel is accounted for. Overall, the production uses Diesel, LPG, Coal, etc... My question is, why not use corn products in this capacity? At the very least, the mills producing the ethanol and byproducts such as corn oil have an already existing source of energy already on hand. Corn oil is very similar to diesel fuel, and can be burned in a modified diesel engine. Ethanol, naturally, is a fuel in its own right or we wouldn't be talking about it. Couldn't the mills reduce their own fuel costs by using the freshly generated corn fuels to power themselves? Also, sell them back to the farmer producing the corn at a preferential rate. After all, if you're producing millions of gallons of the stuff, surely it would be more efficient to put some in a holding tank and cycle it back in than to sell it, have it trucked around, and have some coal trucked back for your furnace. All that trucking is part of what increases the embodied energy, and reduces its own energy value.
This is the same USDA that says we don't need labels on genetically modified food, too! Oh, yeah, I trust this study -- as far as I can flush it.
If all this should have a reason, we would be the last to know.
There is more than 1 source of energy:
When looking at a possible "energy source" we only look at the energy we use up - ie. fuel, not that which we get for free - ie. solar. The claim is that the fuel used has more energy than the ethanol produced - which can still be economically viable due to subsidies.
This report is very good news (if it is true) because it means that if ethanol and other corn derivatives can fuel their own extraction process (quite possible), then lots of ethanol is produced from a self-sustaining farm.
The energy "produced" comes originally from the sun, as do all forms of energy used by man, apart from geothermal and probably nuclear.
A an aside, shoal oil (I believe) is an example of a fuel which requires more energy to get out of the ground than it produces. In Canada "stranded gas" (no pipeline) is used to extract the oil (which is easier to transport). Take this with a grain of salt, as I don't have references with me.
Another option is to write off biologicals altogether and produce ethanol (or methanol, which is easier and still a good fuel) directly from CO2 and hydrogen.
You need a power plant to supply the electricity to produce the hydrogen, so this is an energy storage scheme as opposed to an energy collection scheme, but I strongly suspect that the end-to-end system efficiency will still be greater than with corn fermentation.
This has the advantage of letting you build the infrastructure for alternate fuel production (hydrogen or methanol, which can be processed by fuel cells and stored at far higher density than hydrogen) without having to replace every car on the road (an internal combustion engine can burn methanol).
Cost for the methanol (or ethanol) is potentially very cheap, even with high energy costs. The efficiency of the methanol synthesis step is what will limit price (and of atmospheric CO2 extraction if you get tired of shipping in limestone).