This week, the city of Ann Arbor, MI began deploying four of the first 25 trucks equipped with an Eaton Corporation hydraulic launch assist system. Ann Arbor mayor John Hieftje and Clean Energy Coalition executive director Sean Reed presented one of the new recycling trucks at the city's Wheeler service center.
The hydraulic launch assist (HLA) system operates on a principal similar to other hydraulic hybrid systems we've seen. A pair of accumulators store energy captured during braking and release it during acceleration. The HLA is a parallel hybrid with a hydraulic pump motor connected to the drive-shaft through an electronically controlled transfer case clutch.
The system was actually originally developed at the EPA national laboratory in Ann Arbor. Engineers employed there are encouraged to come up with new ideas and patent them. The technology is then shared with privately owned companies for commercialization. Eaton is one of several companies developing hydraulic hybrid technology variants, including series hybrids. The Eaton HLA was first seen on the 2002 Ford F350 Tonka concept and Ford has been evaluating it for use in big pickups and vans, although no production variants have been announced yet.
HLA cuts fuel consumption of the trucks by about 15-20 percent in this type of application that includes frequent starts and stops. The four trucks are expected to save $73,000 in fuel costs over their 10 year useful life, along with $26,500 in reduced maintenance costs. These trucks make an average of about 1,000 stops a day and conventional versions require new brakes every three months or so. The HLA-equipped versions recapture about 75 percent of the kinetic energy of braking and only require brake maintenance once a year. The payback time for the extra initial cost is estimated at two to three years. Future versions could reduce operating and acquisition costs further through the use downsized engines and transmissions.
Photos Copyright ©2010 Sam Abuelsamid / Weblogs, Inc.
Clean Energy Coalition Helps Ann Arbor Acquire Innovative,
Locally Invented Hybrid Technology
Ypsilanti-based Clean Energy Coalition secures federal stimulus money to help add innovative hybrids to Ann Arbor's recycling truck fleet
Technology invented by the U.S. EPA lab in Ann Arbor stores braking energy in hydraulic fluid – not batteries
Fuel savings of up to 30 percent expected
Ann Arbor, Mich. – An innovative fuel-saving technology invented in Ann Arbor will be powering four new trucks the city is using to launch its single-stream recycling program, thanks to federal stimulus money secured by the Clean Energy Coalition (CEC), a nonprofit, nonpartisan organization based in Ypsilanti. The CEC is dedicated to expanding the use of clean energy technologies in Michigan.
"There are more options than ever before to help people, businesses and government save money at the pump, reduce our dependence on oil and improve air quality," said Sean Reed, executive director of the CEC. "But it's easier to be a follower than a leader unless there's a catalyst for change. Our job at the CEC is to help create more conservation leaders, and we do that by building public and private alliances and securing resources for them to be a driving force in market transformation."
On behalf of the City of Ann Arbor, the CEC was able to secure approximately $120,000 under the American Recovery and Reinvestment Act of 2009, which it is using to help defray the incremental cost of purchasing hydraulic hybrid trucks. The innovative trucks are built using a technology pioneered by the U.S. Environmental Protection Agency's National Vehicle and Fuel Emissions Laboratory in Ann Arbor.
The new hybrid system stores braking energy in hydraulic fluid, instead of in a battery pack as in nearly all automotive hybrids. It is particularly well suited to heavy-duty trucks that do a lot of stop-and-go driving, because of its overall efficiency and relatively low cost.
According to Eaton Corporation, one of the EPA's development partners for the technology, and manufacturer of the Hydraulic Launch Assist (HLA) system used on Ann Arbor's trucks, the city can expect fuel economy savings of up to 30 percent compared with a conventional diesel powertrain. Maintenance costs for systems such as the brakes also are projected to be lower. The HLA system was launched commercially last fall, so Ann Arbor is one of the first customers.
"Putting a fuel-saving technology invented right here in Ann Arbor on the road in the city of its birth moves the community closer its sustainability goals and helps establish hydraulic hybrid technology in the marketplace," Reed said.
In addition to helping Ann Arbor meet its clean energy goals, the CEC is involved in clean energy projects across the state, including:
Investments in infrastructure, such as the installation of ethanol and compressed natural gas refueling stations
Developing and hosting workshops on clean technologies
Auditing both residential and commercial buildings to help measure their energy intensity and develop efficiency and conservation plans
Providing technical consulting services to 40 municipalities across the state to shepherd more than $10 million of investments in new energy efficiency and renewable energy projects
Championing the adoption of innovative technologies, ranging from LED street lighting to the advanced hydraulic hybrid system
Founded in 2005, the CEC's clients and partners include the cities of HYPERLINK "http://www.bentonharborcity.com/" \t "_blank" Benton Harbor, HYPERLINK "http://www.detroitmi.gov/" \t "_blank" Detroit, HYPERLINK "http://www.cityofflint.com/" \t "_blank" Flint, HYPERLINK "http://www.hamtramck.us/" \t "_blank" Hamtramck, HYPERLINK "http://www.highlandparkcity.us/" \t "_blank" Highland Park, Muskegon Heights, HYPERLINK "http://www.pontiac.mi.us/" \t "_blank" Pontiac and HYPERLINK "http://www.saginaw-mi.com/" \t "_blank" Saginaw, as well as prominent companies and institutions, such as the U.S. Department of Energy and EPA, FedEx Ground and the University of Michigan, among others.
About the Clean Energy Coalition
The Clean Energy Coalition is a nonprofit, nonpartisan organization dedicated to promoting clean energy technologies as a way to create healthier, energy independent communities. CEC implements, manages, and evaluates cost effective, market transformation projects and programs in the building and transportation sectors. For more information visit HYPERLINK "http://www.cec-mi.org" www.cec-mi.org.