In honor of Earth Day (today, April 22nd) I’m going on an environmental extravaganza, with “green” postings throughout the day.
For my earth day post about cars I’m choosing to blog about how some of the current trends in the automotive world aren’t as green as they may seem to be: hybrids and corn ethanol. I’m excited about the fact that our car-loving culture is trying (pretending?) to find ways to reduce its impact on the planet. However I have some serious doubts concerning whether hybrid vehicles and ethanol derived from corn will be the saviors they’re sometimes purported to be. In some cases they may not even be any better for the environment than the cars we drive right now …
A while back there was a bit of a stir when an article appeared in a college newspaper alleging that the Prius outdoes the Hummer in overall environmental damage. While I don’t necessarily agree with everything the article says, I do think that some folks who are trying to be environmentally friendly conveniently overlook the environmental implications of manufacturing hybrid cars. All current model hybrids use some type of nickel-metal hydride battery pack. Manufacturing such batteries requires a great deal of energy and resources. While the specific process outlined in the original article may be somewhat dubious, there is no denying that some amount of damage is done to the environment in the manufacture of these batteries, even if only from generating the energy used to produce them. Therefore, each hybrid car sold bears some amount of additional environmental burden that it must overcome before it can be considered better for the environment than a traditional car.
Hybrids are en vogue right now, with new models popping up every day. Everything from full-size SUVs (Chevy Tahoe Hybrid) to large luxury sedans (Lexus LS 600h) to “mainstream” family cars (Saturn Aura Green Line.) What’s more is that often these hybrids, despite all of their illusions of environmental grandeur, barely get better gas mileage than their gasoline-only counterparts. The Saturn Aura Green Line is a prime example of this, with the hybrid version achieving an EPA average only 2 miles per gallon better in both city and highway ratings.
I’m sure there may be ways, such as “plug-in hybrid” technology, to make hybrids more eco-friendly with regards to the big picture. However, most current hybrids seem to be little more than an attempt by the automakers to cash in on the latest marketing fad. Unfortunately, this is ultimately happening at the expense of the environment.
This country has more corn than it knows what to do with, so why not try turning it into a fuel source? Flex-fuel cars capable of running on ethanol have been around for years, however it has only been within the past few that automakers have begun touting this capability on a large scale. At first blush it seems like a good solution. It gives corn growers an additional opportunity to sell their crops and it helps reduce our dependence on foreign oil, right?
What we consumers don’t often hear is the fact that refining corn-based ethanol only results in roughly 25% more energy than it takes to produce it. In addition, even though ethanol has a higher octane rating than gasoline it contains less energy per gallon, which means that vehicles running on E85 ethanol (85% ethanol, 15% gasoline) only achieve about 75% of the fuel mileage they would on gasoline alone. That means your car that gets 28 MPG using gas would only get 21 on E85 and your SUV that gets 15 MPG on gas would drop to 11 MPG. Ouch.
The government currently subsidizes the production and sale of corn ethanol so that it can be priced attractively less than gasoline. But unless it is priced 25% less than gas it still ends up costing the consumer more. According to the Daily Fuel Gauge Report the energy-adjusted price of E85 is currently about 30 cents per gallon more than regular unleaded gasoline. And that still doesn’t reflect the actual cost of ethanol because of the government subsidies.
So if corn-based ethanol is such a lost cause, what other options might there be? Soy-based fuels, such as soy biodiesel, often have a better energy balance than corn ethanol, but involve some of the same risks with regards to over-farming and competing with food sources. One alternative that I think has some merit is cellulosic ethanol, which can be refined from just about anything that has ever been alive. This includes products that are often discarded like corn stalks and wood shavings from lumber yards. Many proponents of cellulosic ethanol are currently looking towards switchgrass, a perennial grass native to the North American plains, as a viable source for ethanol production. Current estimates put the energy yield from refining switchgrass at 540% (compared to corn ethanol’s 25%.) The first cellulosic ethanol refineries have yet to come online, but when they do ethanol may finally become a truly viable alternative to gasoline.
Personally I find myself most excited by efforts like the smart fortwo where auto manufacturers are being ecologically mindful at all steps of the production process and seeking to create very efficient “conventional” cars. Even though I have my doubts about whether I could personally justify getting a smart car, it would be great if more car companies would follow a similar model of environmental management and recycling in their own business practices.
So what are your thoughts on the current (not-so) green fads in the auto world? Think I’m being a bit too critical? Want to voice your hearty support? Hit up the comments and speak your mind! You can also check out Scientific American’s article on switchgrass ethanol and Popular Mechanic’s article on converting cellulose directly to gasoline for more reading on this subject.