MIT Study Finds Aluminum-Intensive Vehicles Fall Short of Environmental Claims
26 May 1999
MIT Study Finds Aluminum-Intensive Vehicles Fall Short of Environmental Claims Challenges Aluminum Industry Claims
NEW YORK, May 25 -- Compared to the UltraLight Steel Auto
Body (ULSAB), it would take 32 to 38 years of driving aluminum-intensive
vehicles to offset the amount of carbon dioxide (CO2) put into the atmosphere
by the production of the aluminum needed to build those vehicles, according to
research by the Massachusetts Institute of Technology (MIT).
The research seriously calls into question the aluminum industry's claim
that a one ton increase in the use of aluminum in automotive applications in
place of steel would reduce C02 emissions by 20 tons over the life of an
average vehicle.
The recent study by MIT's Materials Systems Laboratory examines the
comprehensive environmental impact of C02 emissions and other polluting
substances resulting from the production and use of various automotive
manufacturing materials, including aluminum, steel and composites. The study
considers CO2 emitted when generating electricity, producing aluminum, the
time required to offset the initial atmospheric burden, and created during
production, versus any environmental benefits derived from the use of
aluminum, among other factors. As part of its continuing work, MIT expects to
report additional results later this year.
The aluminum industry claims that because aluminum is lighter than steel,
auto makers can use it to build lighter cars that will burn less fuel during
their lifetimes and thus, emit fewer harmful tailpipe emissions, including
C02. However, producing one ton of virgin aluminum generates approximately
10 times more carbon dioxide emissions than the production of a ton of steel.
"Typically, life cycle analyses have been oriented to use of a product, in
this case, the automobile," said Dr. Joel Clark, Professor, Massachusetts
Institute of Technology, during a press briefing at the Annual General Meeting
of the American Iron and Steel Institute (AISI). "However, the patterns of
use and the distribution of emissions over a vehicle lifetime suggest that it
is important to consider the entire fleet of vehicles when examining the
relative environmental merits of alternative product designs."
Unlike single product manufacture, fleet production occurs progressively.
An existing fleet does not change overnight when an alternative vehicle
decision is introduced. Instead, benefits are gained incrementally as each
new vehicle is added to the fleet. Because of the rate of vehicle retirement
in the United States, it takes more than 15 years to replace an existing
automobile fleet.
The MIT study challenges the validity of the assumption that using
hydroelectric power to produce large quantities of virgin aluminum will create
no new CO2 emissions. "One cannot assume that the incremental electricity
requirement for production of new virgin aluminum for future use in
aluminum-intensive vehicles will be hydro," said Clark. "According to DOE
projections, this additional electricity will be supplied by coal-fired
plants, which eventually will be supplanted by gas-fired electricity
generation plants."
The MIT research also demonstrates that any improvements in powertrain
efficiency and corresponding reductions in C02 emissions will lengthen the
time it takes to offset aluminum's initial CO2 burden. As cleaner power
sources become cleaner and more prevalent, the need for expensive and
difficult solutions, such as provided by aluminum diminishes, and steel
solutions become increasingly attractive. This will be especially true once
totally clean power sources such as fuel cells become more commonplace.
This high initial atmospheric loading of CO2 by aluminum, coupled with the
fleet effect, means that it would take decades -- not the five to six years
claimed by aluminum producers -- for fleets of aluminum-intensive vehicles to
reach a "crossover" point where their total CO2 releases drop below those of a
steel fleet using ULSAB concepts. Even compared to today's conventional
steel-intensive fleet, a hypothetical aluminum-intensive fleet still would
take some 15 to 17 years before its total CO2 releases reach the crossover
point, assuming no improvements in automotive powertrain technology.
"The MIT study strongly suggests that a large scale shift to aluminum
intensive vehicles could make the CO2 problem worse -- not better," said Paul
Wilhelm, AISI Chairman and President of U.S. Steel, who also spoke at the
briefing. "This research has significant implications for our auto customers
who are making decisions on materials for future generations of vehicles.
Consumers who would buy an aluminum car thinking that they are helping the
environment, unfortunately, would be making a mistake."
"We believe that if auto companies remain committed to steel-based
solutions, such as ULSAB, and continue to improve powertrain efficiency, they
can avoid using much less environmentally friendly materials and enhance the
benefits to mankind."
The global steel industry has demonstrated the weight reducing potential
of its material through research and development projects such as ULSAB.
Through the use of advanced steels and sophisticated design techniques, ULSAB
has shown the potential to reduce the body mass of mid-size cars by up to
36 percent, compared to a representative benchmark group of mid-size cars in
the 3,300-pound curb weight category.
"Use of aluminum sheet in particular, compared to steel, presents a range
of problems in addition to significantly higher initial CO2 atmospheric
burden. These include higher cost and more difficulty in handling, stamping,
assembly, repairability, and recycling, all of which are strengths of steel,"
said Wilhelm.
The American Iron and Steel Institute (AISI) is a non-profit association
of North American companies engaged in the iron and steel industry. The
Institute is comprised of 48 member companies, including integrated and
electric furnace steel makers, and 175 associate and affiliate members who are
suppliers to or customers of the steel industry.
For more news about steel and its applications, view American Iron and
Steel Institute's website at http://www.steel.org.
The Automotive Applications Committee (AAC) is a subcommittee of the
Market Development Committee of AISI and focuses on advancing the use of steel
in the highly competitive automotive market with offices and staff located in
Detroit, cooperation between the automobile and steel industries has been
significant to its success. This industry cooperation resulted in the
formation of the Auto/Steel Partnership, a consortium of Chrysler, Ford and
General Motors and the member companies of the AAC.
This release and other steel-related information are available for viewing
and downloading at American Iron and Steel Institute/Automotive Applications
Committee's website at http://www.autosteel.org.
Automotive Applications Committee member companies:
AK Steel Corporation
Acme Steel Company
Bethlehem Steel Corporation
Dofasco Inc.
Inland Steel Company
LTV Steel Company
National Steel Corporation
Rouge Steel Company
Stelco Inc.
US Steel Group, a unit of USX Corporation
WCI Steel, Inc.
Weirton Steel Corporation
