Concept Cars Unveiled at NAIAS
The 2007 North American International Auto Show (NAIAS) in Detroit, Michigan, was home to many exciting announcements and unveilings related to alternative fuels and advanced technology vehicles. Perhaps the largest unveiling was Chevrolet’s Volt Concept, a plug-in hybrid electric vehicle which General Motors (GM) had previously announced was under development.
The Volt’s drive system, called “E-Flex,” has an alternating current motor, which powers the front wheels. A 1.0-liter, three-cylinder turbocharged engine, capable of running on E-85 ethanol, powers a 53-kW generator. There is no mechanical linkage between the gasoline engine and the wheels. In its current configuration with a 12-gallon fuel tank, the vehicle has a range of 640 miles. The E-Flex platform allows for easy integration of other engines that run on alternative fuels, such as biodiesel, or replacing the engine with a hydrogen fuel cell.
The Volt features a built-in 110-volt conductive charger instead of the inductive paddle charger found on the EV1. The batteries consist of 16-kWh lithium-ion battery pack. Even with the batteries completely discharged, the gasoline engine is capable of generating enough electricity to run the car at 70 mph, while at the same time completely recharging the batteries in thirty minutes. When the battery pack is recharged from an electrical outlet, the charge time is about six hours. Unfortunately, GM says that lithium-ion batteries meeting all of the specifications and cost requirements for the Volt are not yet available. GM estimates the batteries will be available by 2010.
GM’s release of the Volt concept demonstrates that plug-in hybrids will likely be a viable option in the near future. The shortcomings of an all-electric vehicle like the EV1, such as limited range and practicality, have been addressed. The Volt concept also provides a way for hydrogen-powered fuel cell vehicles to eventually enter the market. At this point, it seems likely that any hydrogen vehicle released in the near future will have plug-in capability because of the high cost of hydrogen and low cost of electricity.
The NAIAS also featured several more traditional hybrid vehicles:
Several production and concept vehicles featured at the NAIAS were flex-fuel vehicles, which are capable of running on up to 85 percent ethanol. These included the Mazda Ryuga, Ford Interceptor, and Lincoln MKR. The Saab Biopower concept vehicle runs only on 100 percent ethanol fuel, and thus is able to take advantage of the ethanol’s higher octane rating by increasing the compression ratio. The Biopower is also a hybrid, featuring three electric motors to improve acceleration and fuel economy.
Diesel-powered vehicles, which could possibly be run on biodiesel, were shown by several automakers. One of the vehicles that DaimlerChrysler showcased its BlueTec diesel engine technology in was the Jeep Trailhawk concept, which Jeep described as a cross between a Wrangler and Grand Cherokee. Mitsubishi also announced plans to sell small diesel engines in production vehicles by 2010.
Another interesting concept was the Ford Airstream, a hydrogen-powered concept vehicle produced by a partnership between Ford and Airstream. Featuring retro styling with cutting-edge hydrogen technology, the vehicle uses a Ballard Fuel Cell to recharge lithium-ion batteries and also has plug-in recharging capabilities. One of the major advancements on this fuel cell is that it is capable of operating at temperatures below freezing. The wheels are driven by electric motors, which receive power from the battery pack, not from the fuel cell. The fuel cell operates at steady state to maintain the charge of the battery pack. By doing this, the size and weight of the fuel cell can be reduced by half. This also results in a significant cost reduction.
The alternative fuel and advanced technology vehicles shown at this year’s NAIAS demonstrate that nearly all automakers are focused on developing the cleaner, more fuel-efficient vehicles which consumers desire. It also shows that the way we will reduce our reliance on foreign oil and reduce emissions will most likely be from a variety of different fuels and technologies, not just one solution.