San Francisco, November 15, 2006
They’ve been on the road for nearly a decade, but the overall environmental impact of hybrid vehicles has remained largely a mystery until now. A new study from AAA of Northern California finds that, while the immediate changes are relatively small, the potential oil savings and greenhouse gas reductions due to hybrids could have dramatic consequences.
The study, conducted by researchers at the Institute of Transportation Studies at UC Davis, analyzes the current impact of hybrids on oil consumption and toxic emissions and projects their overall impact on the environment in real-world terms like tankers of oil saved and number of trees planted.
“We recognize that hybrids are only a small percentage of the 17 million cars and trucks sold in the U.S. each year,” said AAA of Northern California spokeswoman Jenny Mack. “But sales are increasing, and AAA felt it was important to examine the impact of this growing trend.”
On an individual basis, the impact of driving a hybrid car is significant. On average, the study found that a hybrid vehicle reduces lifecycle greenhouse gases by about 30 percent compared to a conventional vehicle. Fuel consumption drops even more significantly, by an average of 35 percent.
Using sales projections and trend analysis, the study finds that by 2010, hybrids will make up about 1.2 percent of the total miles driven in the U.S. each year. This means hybrids will reduce 0.4 percent of total oil consumed and greenhouse gas emissions in the U.S. While that may not sound like much, it’s the equivalent of 498 million gallons of gasoline per year, or about ten fewer tanker shipments from foreign oil suppliers.
The 0.4 percent reduction in greenhouse gases equates to an annual reduction of about 5.1 million metric tons. Since each conventional car emits about eight tons of carbon dioxide per year, reducing annual greenhouse gas emissions by 5.1 million metric tons is like removing 637,500 cars from the roads.
As more automakers and consumers embrace hybrid technology, there is reason to believe the market might expand even more rapidly. If hybrids were to make up 10 percent of the total miles driven in the U.S., the environmental impact would be much more significant.
Hybrids would save over five billion gallons of gasoline each year, or the equivalent of 119 large tanker ships. Greenhouse gas emissions would drop by 42.4 million metric tons. You would need to plant and grow to maturity 42 million trees to offset that amount of carbon dioxide emissions.
Other benefits of hybrids are not as easy to quantify. The introduction of hybrid electric vehicles (HEVs) has essentially created a new “green” market for automakers. Like the market for safety in vehicles, manufacturers were initially cautious about safety features like airbags and ABS brakes in their cars, believing that consumers would be unwilling to pay for the increased cost of these enhancements. Now, crash ratings and safety equipment are top concerns for car buyers and a standard part of marketing and improving vehicles. The same phenonmenon is now happening with “green” vehicles like HEVs. Eventually, the emissions and efficiency of vehicles will become a normal aspect of car marketing.
“Think of hybrid cars as a gateway to other vehicle advancements,” said Rusty Heffner, author of the UC Davis study. “By introducing a new kind of technology into the marketplace, HEVs have encouraged innovation in the market and have sparked interest in other developing technologies like plug-in hybrids, electric cars, and fuel cell vehicles.”
The arrival of HEVs is already having an effect on consumers. Most research on hybrids assumes that consumers would purchase an equivalent conventional vehicle if a hybrid were not available. For example, someone purchasing a Honda Civic Hybrid would buy a regular Honda Civic, or someone buying a Toyota Prius would buy its closest equivalent, the Toyota Corolla.
Researchers at UC Davis have found that this assumption isn’t necessarily accurate. When researchers interviewed Prius owners, none had even considered a Corolla. In fact, many had owned larger and more luxurious vehicles and the Prius was a purposeful attempt to reduce their use of gasoline and production of emissions. In the absence of a Prius, most would have bought something similar to their previous vehicle. Researchers further found that households with a hybrid and at least one other conventional vehicle tend to switch more of their driving to their hybrid car.
“While it will likely take decades before hybrids make up enough of the total auto market to achieve double digit oil and emission reductions, reductions in the projected 1-to-10 percent range are huge improvements,” said Mack. “Most importantly, hybrids have raised the bar on fuel economy for all technologies, creating competition that will push improvements for conventional vehicles and energize the development of new options.”
The study is part of AAA’s Greenlight™ Initiative, AAA’s program to promote the understanding and development of alternative fuels and vehicles. More information about the Greenlight Initiative is available at www.aaa.com/greenlight.
AAA of Northern California offers a wide array of automotive, travel, insurance and financial services to more than 4 million members. AAA has been a leader and advocate for the safety and security of all travelers since it was founded more than 100 years ago.
