Rural Ways is always looking for ways to save money on energy. Not because we are righteous, but because we are cheap. One way to do it is to spend less on motor fuel for the cars. We have tried to do that by combining trips, driving gently, and keeping our tires in shape . . . all the obvious stuff. Nevertheless our costs have been rising inexorably. One reason for this has been a decline in mileage from both of our vehicles. Granted the cars are old, but there doesn't seem to be any good reason why our efficiency would drop by 5 or 10 percent in miles per gallon in both vehicles. Recently, however, someone mentioned that the more ethanol there is in your petrol, the worse your mileage will be. So, I looked it up.
It takes one gallon of fossil fuel to produce 1.34 gallons of corn ethanol in the United States. (There are some who dispute these numbers, but the numbers come from the Argonne National Laboratory, so I'll live with them.) Great. We're getting a third more energy out for every gallon we put in. Umm, not so fast. The bad news, and the thing I guess I didn't realize is that there are only about 85,000 BTUs of energy in a gallon of ethanol, as compared with 124,000 BTUs in a gallon of gasoline. That is about a third less energy. Now, Rural Ways is not mathematically inclined, so readers can feel free to check my arithmetic, but it seems like the benefits of ethanol may be hovering somewhere in the range of slim to none.
What really gets my goat, however, is the effect of all this ethanol on my fuel consumption. Consumer Reports says that at least 70% of the fuel you buy at the pump is a 90/10 mix of gasoline and ethanol. In 2009, the US EPA allowed this ratio to go to 85/15. (You may have started to see the stickers on the gas pumps stating that your fuel may contain up to 15% ethanol.) This means that, at 90/10, every gallon of gas we pump contains 120,000 BTUs of energy, or 3% less than we'd get from straight petrol. At 85/15, every gallon contains about 118,000 BTUs, or 5% less energy than gasoline.
So, let's take the worst case scenario: Rural Ways drives an old pick-up that could (formerly) be counted on for about 15 MPG. If we are fueling it with a 15% ethanol blend, that goes down to about 14 and a quarter. At $3 per gallon spread over a year of driving (12,000 miles), our costs go up by $124.17. The car only costs an extra 74.50 due to its smaller motor, but, together, we are going to pay an extra $200 for motor fuel in 2011. Now, to many, that may seem a small price to pay for a reduction in greenhouse gas emissions, but, according to the ANL, a 90/10 gasoline/ethanol blend only reduces our GHG emissions by 2%. So, wait? We burn 3% more to reduce our emissions by 2%? I'm still having trouble with the arithmetic. Besides, at Rural Ways, $200 is a lot of money.
DD,
ReplyDeleteSince the family farm is now only half a mile from a large ethanol plant, I had good opportunity to learn a few things last summer.
Agreed that the whole mileage aspect is very frustrating (as it the emissions, etc.). It seems to me that the current solution to simply add ethanol into the mixture is mostly (if not entirely) a P.R. gain for Big Brother, to satisfy the greenies. But for engines that aren't specifically made to burn ethanol, it's a bust.
Among the most interesting bits I learned, though, was the the ethanol production process does not simply end with the ethanol. The waste product is a protein rich "mash" that's put back into the food chain (i.e., cattle feed). Thus, the big picture needs to take that into account.
But I was frustrated that no one could seem to answer my larger question: why aren't we seeing 100% ethanol engines, that is, engines made specifically made for ethanol and not just modified gasoline engines. Unless I'm just woefully stupid, it seems that there should be a way to achieve greater efficiency with ethanol that the current situation. And at least corn is more of a sustainable resource than fossil fuel.
And by the way, this stuck-in-a-socialist-country brother is pretty envious of 3$ gas! Up here it typically takes over $75 to fill the 20-gallon tank in the grand caravan, and that's when it's not on empty. Ouch. Talk about a budget buster. (And the Mrs. wants a suburban now that we have five -- good grief, I'd have to get a second job just to pay for fuel.)
It's hard, Big D. Like you, I grew up in a farm town where you'd take home $75 after a week of stacking hay in the hot sun. It doesn't seem real that I can be paying that for one tank of gas. It makes me want to stay home. Which is not exactly the effect desired by the Keynesians who seem to hold the upper hand in today's economic climate.
ReplyDeleteIn any case, the attached link to Consumer Reports has an interesting article about the Flex Fuel vehicles you can buy now. They can run on E85, or an 85% ethanol blend. Interestingly, CR found that their mileage dropped by 22% when they ran the E85 . . . and this is on a vehicle designed to use it. Maybe that is different from what you are talking about with an engine designed exclusively to burn ethanol, but the CR results don't leave me hopeful. On the other hand, The Economist has run a couple articles recently about how Brazil converts sugar cane waste to ethanol for motor fuel in an apparently effective and efficient manner. Now that is something I can get excited about.
DD,
ReplyDeleteYeah, the flex-fuel cars are crap. I was talking about the auto industry getting off it's big butt and actually being innovative. Those ethanols plants are pretty darned complex (I have a brother who works at the one near our farm). If we can design those (and it seems they design higher efficiency equipment every 6 mos. for them), then I have no doubt the auto industry can produce something a heck of a lot better than they're pushing on us now. The cynic in me thinks that they have a long-term plan, in which they force flex-fuel cars on us for 10 years or so, and then come out with a better engine, making the flex-fuel cars obsolete, etc. It's the same as the tech industry -- they're building in obsolescence. But that's the cynic inside...
Gotta walk to the commuter train, because I sure as heck ain't driving to work!