Utility van: More views of Bright Automotive’s plug-in hybrid called the Idea.
The vehicle’s “through-the-road” parallel plug-in hybrid design also cuts costs. In general, plug-in hybrid vehicles use more than one source of power to propel the vehicle. Typically, an electric motor–powered by batteries that can be recharged using an ordinary outlet–is coupled with a gasoline engine that extends the range of the vehicle beyond the distance that it could travel on the energy stored in the batteries alone. In the Chevrolet Volt plug-in hybrid, due out next year, the gas engine serves only as a generator that recharges the battery after it’s depleted–there’s no mechanical connection between the gas engine and the wheels. In this design, the electric motor has to be big enough to provide all of the power needed for acceleration. In contrast, in a proposed plug-in hybrid from Toyota, the gas engine and the electric motor are both mechanically connected to the wheels via a power-splitting device, which controls how much of the power needed to turn the wheels comes from each. In this setup, the motor can be smaller, but the power-splitting device adds cost and weight.
In the Idea design, a gasoline generator powers the front wheels, as in a conventional vehicle, while the rear wheels are driven by an electric motor that draws power from a battery pack. There’s no mechanical connection between either motor, so the only link is the road itself–hence the name “through-the-road” hybrid. When the driver presses on the accelerator, a control system automatically decides how much of the power for accelerating the vehicle will come from gas-powered front wheels and how much will come from the electricity-powered rear wheels. When the battery is fully charged, the van can travel on electricity alone for about 30 miles, although for very fast acceleration, the control system has to call on the gas engine for a boost of power. After 30 miles, the power needed to propel the car comes mostly from the gas engine, but the battery can provide bursts of power as needed for acceleration, or to keep the engine operating at its optimal power range. The battery can be recharged by the gas engine (much as a conventional engine charges the starter battery) or by capturing energy from braking. The vehicle can travel 50 miles between battery charges using half a gallon of gas (equivalent to 100 miles per gallon). But if it has to go further between charges, it uses more gasoline–for example, traveling 70 miles takes one gallon of gasoline.
In this design, the electric motor doesn’t need to provide all the power, so it can be smaller and cheaper than the motor used in the Volt. It also doesn’t need the mechanical power-splitting device used by Toyota, Shuey says.
Bright plans to build its own battery pack using lithium iron phosphate cells, a battery chemistry that’s safer and lasts longer than the lithium cobalt oxide used in laptops and cell phones, but the company hasn’t yet named the battery supplier.
But some experts predict that Bright will have a difficult time competing with other automakers. Mike Omotoso, senior manager of power-train forecasting at J.D. Power and Associates, says that sales projections of 50,000 vehicles are optimistic. “It looks like a good vehicle,” he says, but he adds that “the overall demand for that type of vehicle isn’t as high as they think it is.” What’s more, the company will face competition from Ford, which has announced plans for an electric van to be available starting in 2010. Ford has a much bigger marketing budget, and it already has factories to produce the vehicle, Omotoso says. Bright will also compete with Smith Electric Vehicles and Azure Dynamics, which makes a hybrid delivery truck.