Will we be driving gasoline-powered cars 10 or 20 years from now?
Judging by the 2001 Michelin Challenge Bibendum, some of us will, but many won’t.
The Challenge Bibendum (Bibendum is the real name of the made-of-tires Michelin Man) offers manufacturers an opportunity to demonstrate alternative-fuel vehicles in real-world conditions.
This year’s challenge drew 27 production cars and 18 prototype cars. It included a critique of the vehicles’ design at the Automobile Club of Southern California, a performance test at the California Speedway in Fortuna, and a 430-kilometre drive to Las Vegas.
Several different power sources were used. Six cars in the competition didn’t use an alternative fuel at all–they used gasoline. Technological improvements continue to make gasoline engines cleaner–a new car in Europe, for instance, emits only one 10th of the harmful gases emitted by the average eight-year-old car–and more efficient, which means gasoline engines will continue to be used in cars for years to come.
Two entries were powered by biofuels, fuel made from renewable resources such as plants. Ethanol is the most widely used biofuel; currently it’s usually added to gasoline to improve performance and reduce pollution.
Four entries made use of diesel technology. Although diesel engines have been around since the earliest days of the automobile, they’re gaining renewed attention because they’re more efficient than gasoline engines and emit lower levels of unburned hydrocarbons and carbon monoxide, and because of new technology that boosts performance and fuel economy. Further work needs to be done, however, to nitrogen oxide and soot emissions. It’s estimated that 50 percent of light vehicles sold in Western Europe will be diesel powered within the next few years (in the United States it’s expected to be only three percent).
There were nine electric cars in the competition. Eight were vehicles already in production, but even so, most analysts think that for the foreseeable future, electric cars will only be used for people who don’t have to drive very far. Although battery technology is improving, electric cars’ range is still limited and they require lengthy recharging.
Nine hybrid cars were entered in the competition; they combined small, fuel-efficient gasoline engines with electric motors. Hybrids have more range than pure electric cars, because the gas engine keeps the batteries charged. They even capture and use energy normally wasted as brake heat. The downside: two heavy, expensive powertrains in the same small car.
Propane powered only one prototype entry in this year’s challenge. While propane is a very clean fuel and results in reduced maintenance costs, is also has a lower energy content than gasoline, which means you need a much bigger storage tank, which adds cost and weight.
Compressed Natural Gas powered four production and two prototype vehicles. CNG is the cleanest fossil fuel of all, inexpensive, and gentler to an engine than gasoline. But, like propane, it requires a big storage tank, and even with one, can’t match the range of a gasoline-powered vehicle.
Hydrogen, which burns nearly pollution-free, producing primarily water vapor, powered two prototype vehicles (including one of the most unusual a replica of a 1965 427 Cobra!). The big problem with hydrogen is that it must be compressed and stored in bulky tanks, and provides even less energy by volume than propane or CNG. It’s also expensive.
Hydrogen doesn’t have to be burned directly, though; instead, it can be used to produce electricity in a fuel cell, some version of which powered nine prototype vehicles from seven different manufacturers. Fuel cells are two to three times more efficient than a gasoline engine, produce no emissions except water, and are proven technology already in use in spacecraft. Until recently, their cost and size precluded their use in automobiles, but new cheaper, smaller fuel cells are now available. In fact, most major manufacturers plan to have fuel cell-powered cars in production soon, some within a year or so.
On the down side, fuel cells are still expensive, the cylinders to store hydrogen are still big, costly and heavy, and, of course, there is no network of hydrogen fueling stations. That probably means the first fuel cell-powered cars will have on-board devices that create hydrogen from gasoline or methane–but that adds complexity, weight and cost.
Cars using every type of power received “A” grades in some aspect of the challenge, indicating no one alternative power source holds a clear advantage. But Michelin’s Challenge Bibendum shows that there are other ways to power cars than with the gasoline engines we’ve been using for more than a century–and hope for cleaner air in the future.
