Driving Michelin's Zero-Pollution Car

Working in a skunkworks in Switzerland, researchers have developed the Hy-Light, a fuel-cell car that drives 80 mph and refuels at a solar-powered pump

by Bruno Giussani

Electric motors and suspension components are embedded within the wheels Michelin developed for its prototype Hy-Light.

Michelin's prototype Hy-Light car runs is powered by a hydrogen fuel cell.

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While every carmaker in the world is tailing the successful Toyota (TM) Prius by developing low-emission hybrid models of various kinds (flex-fuel; gasoline-electric; gasoline-natural gas; gasoline-hydrogen), the real innovation in automotive is taking place in a nondescript industrial building on the outskirts of the Swiss town of Fribourg.

There, recently, Pierre Varenne sat me behind the wheel of a small prototype called Hy-Light and told me to drive. I found myself in a silent car with great speed and acceleration and amazing stability, but no gear box, clutch, or anti-roll bar. And it produces zero air pollution. As we stopped beside a group of solar panels, Varenne pointed and said: "That's the fueling station."

Switzerland may seem an unlikely home for the reinvention of the auto industry, since there are no Swiss carmakers. Yet that also frees Varenne from the pressures of domestic car and oil conglomerates, creating an ideal environment for his project. This soft-spoken engineer with sharp opinions believes that the only way to truly reinvent the car and make it sustainable is to also reimagine the system that procures the energy to power it. "We need to create 'clean' cars as well as 'clean' ways to generate the energy," he says.

Discreet Presence

Working for tiremaker Michelin, Varenne runs a small group of researchers who are really thinking differently about the future of the car and of mobility. And they have a real car to show, not just a concept: The Hy-Light is registered with the Swiss department of motor vehicles (hence, it complies with all existing regulations), carries a regular plate, and has been discreetly travelling the Swiss roads and highways and showing up at specialized fairs for a couple of years now.

The Hy-Light is a car built around a hydrogen fuel cell, meaning it generates electricity through a basic chemical reaction involving hydrogen and oxygen. The gases are stored in two specially developed tanks (the hydrogen is pressurized and its tank can withstand the direct shot of a Swiss Army rifle). Probably the only drawback of the vehicle's design is the need to fill two tanks, which currently takes roughly eight minutes total.

The Michelin prototype is a catalog of clean-tech innovations. The key novelty is its "active wheel": the electric motors (which weigh a few kilos each) and the suspensions are lodged inside the wheels. "We have designed a system made of a central energy production unit (the fuel cell) and two or four peripheral energy usage units (the motors in the wheels)," explains Pierre Varenne. "In between, there are only electric cables."

Great Stability

The fuel cell used in the Hy-Light prototype was developed by the Paul Scherrer Institute, a leading Swiss research center. What sets it apart from most other automotive fuel cells (such as the one in the GM (GM) Sequel) is that it uses pure oxygen from a tank. Most fuel cells suck oxygen from the surrounding air, but that approach requires an onboard compressor and a system for controlling air quality—all of which lowers the efficiency of the power system. According to Varenne, the Hy-Light method increases the efficiency of the fuel cell by almost one-third. Michelin is now working on the next iteration of the fuel cell.

Electric motors have an advantage in that they can become energy generators. In the case of the Hy-Light, when the car slows down or the driver brakes, the kinetic energy produced by the vehicle's motion is captured and stored, to be released when the driver accelerates. The energy is stored in supercapacitors: an ingenious compromise between a battery (which can store a lot of energy but isn't good at delivering bursts of power) and traditional capacitors (which offer phenomenal power but little storage). Made by Maxwell in Switzerland, this technology increases the car's power for acceleration without increasing its energy consumption.