Engineering students at the University of California, Davis unveiled “Trinity,” a plug-in hybrid vehicle that is the team’s entry in the national Challenge X competition, sponsored by GM and the US Department of Energy. (Earlier post.)
Trinity is a 2006 model Chevy Equinox SUV powered by electric motors and a small internal combustion engine that can run on gasoline or ethanol, augmented by hydrogen injection. Trinity is a PHEV 40—the electric motors and batteries provide power for driving at low speeds and for a range of up to 40 miles, and the gas engine supplies additional power for longer journeys and highway driving.
|Original Equinox vs. Trinity Plug-in|
|Original Equinox||UCD Trinity|
|Acceleration 0-60 mph||9.1s||7.4s|
|Acceleration 50-70 mph||4.9s||4.9s|
|Fuel economy city||19 mpg||36.2 mpg|
|Fuel economy highway||25 mpg||38.7 mpg|
(All electric range)
|0 mi||40 mi|
|Highway range||415 mi||275 mi|
|Mass||1,686 kg||1,985 kg|
|Effective fuel economy||21 mpg||~200 mpg|
The UC Davis Team Fate advisor is Prof. Andy Frank, professor of mechanical and aeronautical engineering at UC Davis. Frank is widely credited as being the inventor (around 1990) of the modern plug-in hybrid, and he testified last week before Congress on the potential of the architecture. (Earlier post.)
Computer models run by the team show that Trinity’s average gas consumption in everyday use could reach about 200 miles per gallon, assuming an all-electric range of 40 miles, said graduate student Peter English, outreach coordinator for the team.
The Trinity plug-in hybrid system includes:
A UC Davis-modified Continuously Variable Transmission (CVT);
A turbocharger/generator to compress charge air for the engine and to use exhaust gases to recharge the battery pack;
A 3kW hydrogen fuel cell for auxiliary systems such as power steering and air conditioning;
Hydrogen injection into the combustion chamber to allow the engine to operate at higher temperatures and reduce NOx emissions.
Trinity is the latest refinement in a series of award-winning plug-in hybrids built by Frank and his students. Others include “Sequoia,” a Chevy Suburban, and “Yosemite,” a Ford Explorer. The group has also built high-mileage versions of the Mercury Sable and other cars.
The original unmodified vehicle was donated by General Motors and supplied locally by Hanlees Chevrolet of Davis for the competition.
Challenge X is a three-year national competition sponsored by General Motors, the US Department of Energy (DOE) and other partners. Engineering students from 17 universities across North America are challenged to re-engineer a mid-size SUV to achieve better fuel economy and lower emissions. The program provides the opportunity for engineering schools to participate in real-world research and math-intensive development with leading-edge automotive propulsion, fuels, materials and emissions-control technologies.
In the first year (2004-5), teams worked on vehicle design using the same techniques and software as auto industry designers. Over the past year, they have worked on putting their designs together in an actual vehicle, which will compete in field trials in Phoenix in June. In the final year (2006-7), they will refine their vehicles leading up to the final competition.
A team from the University of Waterloo (Ontario, Canada) took first place in year one—which was judged on the basis of design plan, simulations, modeling and testing—with their fuel-cell-powered series-hybrid vehicle design. The Waterloo team, sponsored by Natural Resources Canada and Hydrogenics Corporation, was the only one to use fuel cells in the design.
The University of Akron took second place with a parallel-hybrid design using a 1.9-liter Volkswagen TDI biodiesel-powered engine and a Ballard 65-kilowatt/45-kilowatt drive motor.
Ohio State University grabbed third-place with another biodiesel-electric parallel-hybrid design that featured a Panasonic NiMH battery and a 1.9-liter Fiat 110-kilowatt CIDI engine.
UC Davis ranked seventh out of the 17 teams.