Solar Racer

Test Drive

It looks like a UFO, starts like a turtle, is covered with 2726 solar cells and runs as long as the sun shines. PM's Detroit editor Larry Webster goes behind the wheel of the Continuum, the University of Michigan's sun-powered car.
So futuristic and so technically advanced that it would cost nearly a million dollars to duplicate. Yet this Jet Propulsion Lab on wheels lacks the basic features of even the humblest sedan: a radio, roll-down windows, a heater. I had to slither between the rails of a roll cage to access a cockpit so cramped that it feels as though I’m sitting upright in a Niagara Falls barrel.
Working under the supervision of two faculty advisers, more than 100 very bright and very motivated University of Michigan students took two years to build the vehicle, which is designed to compete in a pair of grueling solar-car races. It’s the latest model in a program that has racked up an impressive record since its 1990 inception: Five wins in the college-only 2400-mile North American Solar Challenge and several top finishes running against Honda, GM and Ford in the 1870-mile Australia-based World Solar Challenge.

I’m about 6 ft tall and weigh 180 pounds, which is 3 in. and 20 pounds too much for the cockpit. After an unsuccessful attempt with shoes on, I go socks-only and clear the small carbon-fiber steering wheel. My knees are practically kissing my chin. Luckily, the controls are on the steering wheel: A lever on the right works the “throttle,” and one on the left activates the brakes. The team designed a dash that displays speed, charge state and distance traveled. They also built a rearview video-camera system and a wireless network that links the car to chase vehicles. The team remotely monitors Continuum with a Prius-like energy-flow graphic.

As I gingerly pull back on the accelerator, the car inches forward at a turtle’s pace. It’s so pokey that a few team members walk alongside as I get underway. Weighing a lithe 480 pounds, Continuum gets all the propulsion it needs from a 16-hp electric motor that resides in the single front wheel. The trike design lowers the car’s surface area, which in turn reduces drag. How slippery is it? “It’s a strategic advantage for other teams not to know,” a cagey Dowling says. He reveals that the team believes a Corvette has five times as much drag as Continuum. But as I am about to learn, when it comes to handling, this is no Corvette.

2010 Toyota Prius, All-New 50-MPG Hybrid Packs Solar Panels, More Power: 2009 Detroit Auto Show
Let's start with the fuel economy. Toyota doesn't have solid EPA figures yet, but they say the new Prius should hit 50 mpg combined. If true, that means the Prius will likely be the most fuel-efficient car sold in North America. The Prius rides on an all-new platform, which Toyota says will improve the car's handling and quietness thanks to revised bushings, more caster angle and an improved stabilizer-bar arrangement. However, like before, this new Prius uses struts up front and a beam axle in the rear. Disc brakes are now at each corner and combine with a new regenerative braking system. The new Prius should be a more refined car too, thanks to improved sound insulation to quell vibration and road noise.

Under the hood, a 1.8-liter Atkinson-cycle four cylinder replaces the current car's 1.5-liter unit and generates 98 hp and 105 lb-ft of torque. When combined with the new hybrid system, the horsepower swells to 134. Toyota says that the larger engine actually helps fuel economy, since the increased torque allows it to operate at lower revs on the highway. That newfound torque also helps the Prius reach 60 mph in an estimated 9.8 seconds—about a second quicker than before. A new electric water pump and a new EGR system aid engine efficiency.

The new hybrid system, Toyota says, is 90 percent new. A lighter transaxle up front reduces torque losses by as much as 20 percent. A new cooling system for the inverter helps reduce the size and weight of that component. Together, Toyota says, the inverter, transaxle and motor are 20 percent lighter than before.

Aerodynamics has played a large role in helping the new Prius reach 50 mpg. In fact, Toyota says, with its .25 Cd, the Prius has the cleanest aero profile of any vehicle in the world. Though the overall height of the car remains the same, designers moved the top of the roof 3.9 in. back. And that solves an issue we've had with the current Prius—it's pointy roof profile. The new Prius looks much sharper. It rides on the same size wheelbase as the outgoing model and is only slightly longer. But there's more cargo room, and the seatbacks were sculpted to provide more rear seat legroom.