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Global Worming By Environmental Defense
Cars: Pollution Solutions in Reach
Ever since Henry Ford turned cars into must-have items, automobiles and America have been intertwined. But the road from Ford's Model Ts to today's cars has been bumpy and uneven.
The ups and downs of fuel efficiency
Nowadays, we have a wider selection of vehicles that go much further and faster. But when it comes to fuel-efficiency, we're pretty much back with the Model Ts. Astoundingly, the 28.5 miles per gallon (mpg) of Ford's Model Ts beats the mileage of many of today's vehicles.
In response to the 1970s oil crisis, the country mobilized to double mileage from 13.4 mpg to 27.5 mpg by 1985. But since then, thanks mostly to increased horsepower and weight in all types of vehicles, fuel efficiency has become static. Collectively, our cars in 2005 go fewer miles on a gallon of gas than our 1980 vehicles. Burning more fuel creates more pollution.
Car pollution adds up and sticks around
We might not picture creating pounds of global warming pollution when we drive, but the exhaust coming out of our car has actual weight — an average household with two medium-sized sedans emits more than 20,000 pounds of carbon dioxide (CO2) a year. That's 10 tons of pollution adding to the greenhouse effect. SUVs tend to emit more global warming pollution than smaller cars — as much as 40 percent more exhaust.
Here's how it adds up: A gallon of gasoline weighs just over 6 pounds. When burned, the carbon in it combines with oxygen to produce about 19 pounds of CO2. Adding in the energy that went into making and distributing the fuel, the total global warming pollution is about 25 pounds of CO2 per gallon. An average car that gets 21 mpg and is driven about 30 miles a day uses 1.4 gallons daily and emits 35.7 pounds of CO2 every day. That's a lot of pounds when multiplied by the millions of cars across the country.
Heat-trapping pollution, like that from cars and trucks, can stay in the atmosphere for several decades to about a century. For instance, some emissions from Ford's 1912 Model Ts are still up in the atmosphere today, thickening the blanket of greenhouse gases that are heating up the planet.
Population growth has helped put more cars on the road, and a strong economy has led to more cars per driver. These trends combined with poor gas mileage mean we're facing a dangerous situation.
The Annual Cost of Lower Fuel Efficiency
Average gas mileage
Average fuel used (based on 12,000 miles per year)
Approximate greenhouse gas pollution
Approximate Cost (based on $2.30/gallon)
50 mpg
240 gallons
2.7 tons/year
$552
40 mpg
300 gallons
3.4 tons/year
$690
30 mpg
400 gallons
4.5 tons/year
$920
25 mpg
480 gallons
5.4 tons/year
$1,104
20 mpg
600 gallons
6.8 tons/year
$1,380
15 mpg
800 gallons
9 tons/year
$1,840
10 mpg
1,200 gallons
13.6 tons/year
$2,760
Driving into the future
For the average, car-owning American, driving is in the top two daily pollution-causing activities. (Electricity use is the other big one, and frequent flights are also an area to watch.) On the bright side, the vehicle you choose and the way you drive it presare the greatest opportunities you have as a driver to trim your global warming emissions.
We don't need to be stuck with "Model T" gas mileage. In fact, no matter what size or type of vehicle you need, there's always a greener -- cleaner and more fuel-efficient -- choice. Cars with better gas mileage provide a triple benefit: they protect the climate, they cut America's oil dependency and they save money at the pump.
Greener cars. Choosing your car wisely is one of the most powerful choices you can make.
When looking for a new car, the Green Ratings on the Yahoo! Autos pages make it easy to comparison-shop with the environment in mind. Developed in partnership with Environmental Defense, the Yahoo! Green Ratings account for both fuel economy and tailpipe emissions.
A hybrid vehicle can be a great choice, of course, if it's available in the size, style and price range you need. But remember that there are a wide range of environmental effects even within a class of vehicles.
You can use the Green Ratings to make a better choice for the environment among the cars that meet your needs. For example, even if you're comparing five SUVs, choosing the greenest-rated one still helps fight global warming, protect air quality, and save gas.
The Green Rating reflects the entire impact a vehicle has on the environment. Nearly all car shopping Web sites and guide books also include fuel economy information. Official gas mileage rategs are available at www.fueleconomy.gov.
Steps for buying a fuel-efficient car
So you're in the market for a car and want to do something about global warming. Here are the steps to take to make the greenest choice.
1. Get the right-sized car that fits your needs.
The first thing to do is identify what the primary use for your vehicle will be. If you have several children and need a car big enough to transport them to soccer practice, maybe you need a wagon or minivan. If you build houses for a living, you probably need a truck for your job. But if you own a boat, say, and take it in and out of the water just a few times a year but will use the car for everyday driving ton and from work, do you really need a truck for the other 363 days? Probably not. If you buy a smaller vehicle that fits your everyday needs, you can use the savings in gas money to rent a truck for your infrequent boat-hauling trips.
2. Find the greenest choice in your size and price range.
Once you determine the right-sized vehicle for your primary uses, use the Green Ratings to find the most environmentally-friendly models. Many models are offered with a range of trims and engines. Both fuel economy and the Green Rating depend on the particular features, so note which trims have the best ratings before you head out to your dealership. Several Web sites can help:
- For one-stop shopping, use the Green Ratings on Yahoo! Autos. This unique resource, developed in partnership with Environmental Defense, provides a 1-100 rating that scores new makes and models according to their overall pollution, including global warming pollution. The Green Ratings are given along with price and other vehicle specs, making it easy to identify the greenest models that meet your other requirements.
- Most car shopping sites compare models according to their fuel economy. Fuel economy is the most important criterion that determines how much heat-trapping greenhouse gas is emitted from a vehicle. Choosing a model that is just a few MPG more efficient makes a big difference in helping to fight global warming over a year of driving, and a huge difference over the many years that most cars and trucks stay on the road.
- At fueleconomy.gov, find out which cars or light trucks get the best mileage and which bring up the rear, or explore your ideal mileage by class, make model or mpg rating. Fueleconomy.gov is the U.S. government's official guide for information on gas mileage, and it also offers information on fuel-saving driving and maintenance practices.
- Environmental ratings for some recent model years can be found on Greenercars.com, a by the independent research group American Council for an Energy-Efficient Economy (ACEEE). It's Green Scores are similar to the Yahoo! Green Ratings, though scaled differently, Greenercars.com gives highlights of the "greenest" and "meanest" recent models free, and a subscription gives access to even more information.
3. Consider whether you need options that add cost and detract from fuel economy.
- Four-wheel drive increases fuel consumption, so if you don't need or use it, don't buy it.
- Avoid add-ons like luggage racks that add weight and/or drag, or get removable ones so you can use them only when needed.
A souped-up engine guzzles gas and adds to global warming. All engines in today's market provide plenty of power for safe and responsible driving. Not playing along with the "horsepower war" will decrease pollution and save money on car payments and at the pump.
Cars don't run on gas alone — at least not all of them. Ironically, sometimes looking ahead means looking backward. Ford's Model Ts were designed to run on either gas or ethanol, an alternative fuel made from grains and from plant or animal waste.
There are many potential benefits to biofuels such as ethanol, which is currently made mostly from corn. For one, they can reduce dependence on foreign oil: one consortium of growers, the Agricultural Working Group, has called on farmers to meet 25 percent of America's energy needs by 2025. Today, nearly every car can run on E10, gasoline blended with 10 percent ethanol. About one in forty cars can run on E85, a blend of 85 percent ethanol and 15 percent gasoline. Find out if your car can run on ethanol.
Now, ethanol wasn't developed to solve global warming, and greenhouse emissions savings from biofuels can vary substantially (e.g., Do farmers forgo plowing to trap more gases in the soil? Do they cut back on nitrogen fertilizers, which release a potent global warming pollutant? Is the fuel made from the grain or, more efficiently, from "stover" — the stalks and leaves?). But some biofuels can help reduce emissions that contribute to global warming. Farmers and refiners are continuing to work on new approaches and processes that can produce low-carbon fuels that yield much greater global warming benefits over time. Consumers should stay tuned.
Rocky Mountain News (Denver, CO) February 10, 2003. The 1912 Model T Runabout went an average of 28 1/2 miles on a gallon of gasoline, according to Ford. It achieved 35 miles per gallon at a constant 20 mph and 32 miles per gallon at 30 mph.
Wang, M.Q. GREET 1.5a Spreadsheet Model. Argonne, IL: Argonne National Laboratory. www.transportation.anl.gov/software/GREET/ (17 Feb. 2006).