FEATURE - Car of the future or a lot of hot air?
Author: Rebecca Harrison
He may not have been totally wrong.
Inventor, car enthusiast and environmentalist Guy Negre has built a car powered by compressed air and hopes it will be chuffing along roads across the world within the next few years.
Inside Negre's car, cold air compressed in tanks to 300 times atmospheric pressure is heated and fed into the cylinders of a piston engine.
No combustion takes place, so there is no pollution. In fact, says Negre, the air from the exhaust pipe is cleaner than the air that goes in, thanks to an internal filter.
The car can be refilled with air at home using an electric compressor and Negre hopes that, one day, drivers will be able to recharge the cars in filling stations in three minutes for as little as three dollars.
The air car, which he says will cost 6,800 euros ($6,700), looks a little like DaimlerChrysler's easy-to-park Smart city car, with one row of seats wide enough for three and a curved, pod-like front end.
"We needed an alternative to the gas-guzzling norm so I decided to make one," the former Formula 1 racing engineer told Reuters at the Paris motor show, where his toy-like run-around nestled among the latest sports cars.
TOO GOOD TO BE TRUE?
Negre, who has been working on the car for 10 years, admits it sounds too good to be true. But he says scores of industry insiders who first scoffed at his invention had been sidling up to his stand for a closer look.
Some point out that, although the car itself pumps out no pollutants, the electricity needed to compress the air still comes from power stations that spew fumes or leave behind hazardous nuclear waste.
Another big obstacle to making electric cars commercially is that, despite decades of research, they still need refuelling far more often than conventional petrol models. Some experts say there is no reason why the "air car" should be any different.
"The concept of a car driven by air is not totally ridiculous," said John Wormald at the Autopolis consultancy, adding that air-powered locomotives were used to help dig Alpine railway tunnels to avoid pumping out toxic fumes.
"But as with all these wonderful ideas, the problem is how much energy density can you fit into a tank," Wormald said. "The car's range will likely be small and I can't see it taking off."
Negre says his CityCAT car runs for a maximum of around 10 hours at low speed before it needs refuelling. He insists this is not a problem as drivers will be able to recharge at home.
Wormald said that would be impossible for anyone without a private garage or a space in a parking lot.
Sceptics might wonder whether the big oil firms will be keen to equip their filling stations with a new technology that spurns petrol for air.
TOWN, NOT COUNTRY
Negre admitted that the CityCAT - which he says has a top speed of around 110 km (68 miles) an hour - will work only as a city car and agrees he will probably not persuade motoring enthusiasts to give up their Mercedes and BMW speed machines just yet.
"It's not a real alternative to the standard car," he said. "It's an urban vehicle that we will market mainly as a second car, targeting mainly women who tend to go for smaller vehicles that they use for short distances."
Wormald reckons the business model is flawed.
"The problem is that people just don't want to buy cars they can only use to drive round towns. They might not bomb off to the country every weekend but they like to know that they can if they want," he said.
But Negre, who describes himself as a motorist who also cares about the state of the planet, rather than an all-out environmentalist, insists the air-powered car is the first viable alternative to conventional petrol-powered vehicles.
"I'm a firm believer that the car means freedom and people will not give up freedom, no matter what it's doing to the environment," he said. "So the only way to save the planet is to come up with a car that doesn't wreck it."