Whether it’s an obsession, a symbol of your lifestyle, or simply a way to carry all your stuff from one place to the next, one thing is for certain: Americans are addicted to vehicles.
In 2006 there were 250,851,833 highway vehicles registered with the United States Department of Transportation – and all those vehicles produce an alarming amount of green house gasses: in 2003, the EPA estimates cars, SUVs, minivans pickup trucks and motorcycles emitted 1152.6 teragrams of carbon dioxide equivalent – or 1,152.6 million metric tons.
While consumers are turning to green automobile technologies, it can be difficult to know which option is the most environmentally friendly. So here at Naturally Savvy, we decided to take the confusion out of car shopping by providing you with the information you need to make the greenest choice for your needs.
The average person owns a gasoline-powered vehicle in the United States, but not all are created equally. The newer the vehicle, the better mileage and fuel efficiency it gets, plus newer vehicles can also run on a gasoline-ethanol mix. The Clean Air Act requires gas stations in cities with high levels of smog to use E10 gasoline, a blend of 10 per cent ethanol and 90 per cent gasoline; this fuel reduces smog-forming emissions.
Better yet, flexible fuel vehicles can run on any percentage combination of ethanol and gasoline. While pure ethanol is hard to come by, E85 – a blend of 85 per cent ethanol and 15 per cent gasoline – is available in many areas in the United States. Pure ethanol is an oxygenate, meaning it does not produce carbon monoxide or ozone, and an octane booster, thereby preventing engine knock. While this fuel burns much cleaner, according to the EPA, it produces less energy than gasoline so you get poorer mileage.
There are other problems with ethanol as well. Since bio-ethanol (the only renewable ethanol) is made from corn and other crops, this fuel reduces the amount of food available for farming and human consumption, which also drives up the cost of these crops. Plus, a background and policy brief for the Government of Australia states the production cost of “fuel ethanol” (a blend of ethanol and gasoline) is twice the production cost of gasoline. So it’s pretty much unsustainable as a primary fuel source for the long term.
Hybrid vehicles offer another option for gasoline-powered vehicles. The Prius was all the rage in 2000, but hybrids aren’t actually all that great. While hybrids use an electric motor, which generates power as the car drives, they still rely on an internal combustion engine and gasoline as fuel. So while they produce electric power as they run and thus use less gas than the average car, they’re nowhere near the newer, cleaner technologies. (There are some models that are essentially electric cars with gasoline on hand for backup, but again, these will produce emissions. Plus, electric cars can indirectly produce emissions.)
With advances in battery technology, electric cars are becoming increasingly popular – in fact, there are more than 4,000 electric vehicles on American roads. The motor in electric cars converts electricity stored in a battery pack into mechanical power. The main drawback is you can only go so far without recharging your battery, but a simple fix is recharge stations in parking garages and lots. The more significant and often overlooked drawback is the source of the electricity: energy sources for plug-in vehicles – whether it’s coal, oil or natural gas – often produces greenhouse gasses. If, on the other hand, you buy or produce green energy such as solar or wind power, then electric cars are the most environmentally friendly, zero emission car on the market.
Car manufacturers are looking in another direction. The hydrogen fuel cell is in place to propel vehicle technology into the future, and if you live in some parts of Southern California, that future is now. A limited number of Honda’s 2009 FCX Clarity are currently being leased in the Torrance, Santa Monica and Irvine. Hydrogen fuel cell vehicles take compressed hydrogen stored in a tank split the atoms and extract the energy from the electrons, generating electricity. The protons and electrons are then recombined along with oxygen, emitting only water vapour and minimal heat, and the electricity is transferred to a Lithium-Ion battery that feeds the electric motor.
The mileage on the Clarity is about 280 miles per tank of hydrogen in EPA-standardized testing, which compares to a car with a mileage of 74 miles per gallon (actual mileage will vary depending on usage). The car is only being released in a few areas in California where hydrogen fuelling stations currently exist, but with more car companies developing hydrogen fuel cell vehicles, you can expect to see more test-sales and fuelling stations popping up.
Of course, this begs the question, How will we produce enough hydrogen for all the cars on roads around the world? Currently, the simplest way to produce hydrogen is through electrolysis, but that requires a lot of water and energy. Researchers in several countries are developing technologies that use solar energy for electrolysis, but this doesn’t address the issue of fresh water consumption in the face of drought. Recently, U.S. Agricultural Research Service inventors and North Carolina State University researchers have developed a technology to find strains of nitrogen-fixing bacteria in soils that produce hydrogen gas. The bacterium cannot recycle the hydrogen they produce, so the hydrogen can be “captured” for fuel. It will be some time until truly emission-free forms of hydrogen are available.
The bottom line: if you are already using solar or wind power in your home or if you can install a solar panel to charge your vehicle, nothing beats an electric car.
Bliss, R. (2008). Hydrogen-Producing Bacteria Provide Clean Energy. USDA. Retrieved at http://www.ars.usda.gov/is/pr/2008/080825.htm
Bureau of Transportation Statistics. Retrieved from
Environmental Protection Agency
Green House Gas Emissions from the U.S Transportation Sector (1990-2003)
Honda. (2008). Retrievd from http://automobiles.honda.com/fcx-clarity/ .
Nowotny, J., Sorrell, C., Sheppard, L., & Bak, T. (2004). Solar-hydrogen: Environmentally safe fuel for the future. International Journal of Hydrogen Energy. Retrieved at http://www.sciencedirect.com/
Parliamentary Library. (2003). Fuel Ethanol. Retrieved from
U.S Department of Energy. Retrieved from http://www.energy.gov/energysources/fossilfuels.htm