Green by Design
Part 1: Greener Tech Today
What makes one car greener than another? Certainly, having high
fuel economy is one factor. Meeting one of the cleanest tailpipe
emissions standards is another. Being manufactured in a clean factory
with safe, non-toxic substances, or using a larger portion of recycled
materials, are further aspects of environmental friendliness. The
key to progress on all of these fronts is design with the environment
in mind.
A quick look at our class-based "Best
of 2006" lists makes amply clear that eco-friendliness
is not limited to a certain technology. Hybrids, of course, have
been stealing most of the limelight when it comes to environmentally
friendly vehicles, but the fact of the matter is eco-friendly technologies
are being outfitted in conventional vehicles as well. Intelligent
engines with features such as cylinder deactivation and variable
valve control; advanced transmissions,
including 6- (and even 7-) speed automatics or continuously variable
transmissions (CVTs); emission control "aftertreatment" systems capable
of cutting in-use vehicle emissions to near-zero levels; lightweight
materials and improved aerodynamic design all do their part to
help make vehicles "Green by Design."
Greener Tech Today
Design improvements developed by automotive engineers are the main
reason that cars have improved so much over the past generation.
Thirty years ago, the average new car got no more than 13 miles per
gallon. Its pollution controls were crude and unreliable. Indeed,
vehicles in general were hardly reliable by today's standards. Cars
were heavier but far less safe. Comfort and convenience features
now standard in common models were absent from all but the most expensive
luxury automobiles.
This year, new vehicles sold in the U.S., even though they are now
half trucks, go 50 percent farther per gallon of gasoline than in
1970, with less than one-tenth the amount of tailpipe pollution.
Most auto factories are cleaner, too; less energy is consumed in
making the materials and running the factories. At least in the United
States, under the watchful eyes of unions, environmentalists, and
the EPA, autoworkers and their communities are exposed to fewer toxic
chemicals than were their parents and grandparents. Three-quarters
of automotive steel gets recycled.
New plastics and composites are being designed with recycling in
mind, and recycled plastics are showing up in new parts such as bumpers.
All of these improvements are a result of better
design. Engines are more efficient, with better components, electronic
controls, and fuel injection instead of carburetors. Catalytic
converters—helped
by cleaner gasoline and working hand-in-hand with computer-controlled
engines—filter out most of the worst pollution. Chassis and
body parts are stronger and lighter, providing smoother, quieter
rides, superior handling, and better crashworthiness. Radial tires
grip and handle better while cutting down rolling resistance. Streamlined
bodies save gas and help cut pollution at highway speeds while reducing
wind noise. All of the cars and trucks that score well in our green
ratings do so because of one or more aspects of improved technology.
Yet, while ACEEE's Green Book® Online helps
you find the best vehicles of today, it also makes it clear that
cars and trucks still have some distance to go in terms of environmental
friendliness. This is particularly true when it comes to fuel consumption
and global warming. The fuel economy of cars and light trucks did
increase from 1973 through the mid-1980s. But until very recently,
it has been slowly but steadily declining overall as automakers put
most of their technology improvements into higher performance and
other amenities. The last few years have seen a minor uptick in overall
efficiency, though we are still at a lower level than the vehicles
released back in 1982. And while new vehicles produce less pollution
per mile than those of years gone by, air quality is still a major
concern because the overall amount of driving continues to grow.
We expect ever more comfort, performance, and reliability in new
vehicles; it's reasonable to expect new cars and trucks to also do
an ever-better job on environmental quality.
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