Auto Impacts:

Posted: October 23rd, 2008 under Green Products.


Last week, on October 15, the Environmental Protection Agency released its 2009 Fuel Economy Guide.  The Guide lists the city and highway fuel economies of models released in 2009, which are the second set of figures based on the EPA’s new testing requirements.  The new tests factor in the effects of higher speeds, acceleration, air conditioning, and cold outside temperatures, and aim to more accurately reflect our cars’ fuel economies.

Criteria Analysis (What’s Being Measured):

Industry Sector/Product Category: Automobiles

Criteria Scope (Product/Company): Product

Attribute(s) Being Measured: Technological Innovation

Life Cycle(s) Under Consideration: Use Phase

Environmental Values Affected: Climate

A definite improvement over earlier tests, the EPA’s new fuel economy score is a relatively narrow and specific measure of environmental performance.  It measures the gas mileage of car models under a variety of conditions, and as such is a good estimate of a car’s greenhouse gas emissions when it is being driven.  It does not, however, take into account the atmospheric pollutants released by these cars, such as particulates and carbon monoxide, and does not cover impacts from other parts of the car’s life cycle, such as its production or its end-of-life.  And it doesn’t factor in differences in the environmental performance of the companies making these cars, the countries they are made in, or the individuals driving them, all of which can have a significant effect on the car’s overall environmental impact.

Methods Analysis (How It’s Being Measured):

Transparency: High

Independent Verification: Limited (10%)

Peer Review: Yes

Data Updates: No (each car model tested only once)

Data Presentation: Data Averages

Criteria Updates: Infrequent (last change was in 1985)

A relatively detailed explanation of the tests, including a slide show and video, is provided, as is the raw data from the tests and manufacturers. Users of the website can also log their own gas mileages, which are then presented along with the government data.

Governance Analysis (Who’s Doing the Measuring):

Involvement of Government Agencies: Extensive (Funding, Leadership, and Decision-Making)

Involvement of Advocacy Group(s): Limited (Comment Period)

Involvement of Citizens: Limited (Comment Period and Data Provision)

Involvement of Academic Researchers: Limited (Comment Period)

Involvement of Companies Being Rated: Limited (Comment Period and Data Provision)

Involvement of Independent Organization(s): Limited (Comment Period)

The Environmental Protection Agency is primarily responsible for the funding and implementation of this program.  However, while the tests were designed and the data is published by the government, they are actually performed by the car manfacturers themselves.  10-15% of the tests are checked by the EPA, but those results do not appear to be made public, and certainly are not well-publicized.  While the “people’s voice” is heard through the posting of user data, the manufacturer’s data is privileged on the site, with no attempt to highlight or reconcile any differences.

This Scale’s “Greenness:”

While the EPA Administrator said that with this Guide, “Americans now have the information they need to buy greener and cleaner cars and trucks,” it is important to keep in mind several points:

The Green: does provide the best measure of a car’s gas mileage, and by extension, its climate impacts during driving.

The Not Green:

It does not, however, measure the overall “cleanness” or “greenness” of a car, if you consider limiting air pollution from exhaust and environmental impacts from manufacturing part of being green.  The EPA’s Green Vehicle Guide, Yahoo and Environmental Defense’s Green Car Center, the Union of Concerned Scientists Automaker Ratings, and CNW’s controversial but interesting Dust to Dust life cycle report are starting places for a more comprehensive perspective.  It also relies on tests by manufacturers, with limited verification, and does not require testing and has no data or many larger pickup trucks and SUVs (over 8500 lbs).

* For a more detailed explanation of the Criteria, Governance, and Methods reviews above, please click here.

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