Is This The Future? Fuel Cell Technology and Driving the General Motors Hy-Wire
By Carey Russ (c) 2003
According to industry pundits, within the next 25 years we will all be driving hydrogen fuel cell-powered vehicles. And, unlike the pie-in-the-sky predictions of nuclear-powered vehicles in the 1950s, this prophecy has a reasonably high likelihood of coming true. Oil reserves are finite, and much of the oil in this planet is in lands not exactly friendly to Western society. Besides being used as fuel, petroleum products are used for structural materials including plastics. With increasing use of plastics in vehicles and decreasing availability of petroleum fuels, another source of fuel will eventually be necessary. That fuel is most likely to be hydrogen.
Hydrogen is the most abundant element in the universe, but that is of little help here on Earth, where it is virtually nonexistent in free molecular form. And, although water is composed of two parts hydrogen and one part water, which can be separated, it currently is not economically feasible to do so. With current technology, it takes more energy to get the hydrogen from water than the hydrogen produces. But technology changes, particularly when there is a need for change. Hydrogen can also be produced from hydrocarbons, chemical compounds composed of hydrogen, carbon, and other elements. The most common fuel hydrocarbons are petroleum, natural gas, and coal... weren't we attempting to wean ourselves from those?
Even when efficient, cost-effective, and environmentally-responsible hydrogen production methods are perfected, distribution will present challenges. Hydrogen is the lightest element in the universe, and is a gas at normal temperatures. It must be pressurized into a denser gas or a liquid, or combined with other substances to form a solid for efficient transport and use as a vehicle fuel. But, if we do really come to the Hydrogen Economy, these problems will be solved. And there are two choices for vehicle powerplants.
Internal combustion fans, rejoice! Don't count the venerable reciprocating piston engine out yet. With surprisingly few modifications, the engine in your car today can run on hydrogen instead of gasoline or alcohol. BMW has been running an experimental fleet of hydrogen-powered cars with modified versions of production gasoline engines for several years, and Ford has a Focus wagon that uses a hydrogen-fueled supercharged and intercooled version of the 2.3-liter engine found in some other, gasoline-powered, Focuses. I had the opportunity to ride in little green wagon - nicknamed ``Kermit'' for obvious reasons - a few months back at the Challenge Bibendum environmental vehicle event. Kermit was an engineering prototype, and so a little rougher-finished than a production car. But other than that, it ran just like a normal gasoline-powered Focus. There is also no reason that a hydrogen internal combustion engine can't be paired with an electric drivetrain to make a hybrid vehicle.
So, in the short term, hydrogen internal combustion and hybrid vehicles may see use. But the current holy grail is the hydrogen fuel cell. Actually, fuel cells are not new - the concept dates to 1839. Fuel cells were used as power and water sources in the Apollo space capsules of the 1960s and 1970s. A fuel cell operates in a manner similar to a battery, but instead of being recharged it is refueled. Put most simply, hydrogen is chemically separated into its component protons and electrons; the electrons produce electricity and the protons combine with oxygen from air (or an oxygen tank in a spacecraft) to form water. Heat is also produced. There are several different types of fuel cell. Some are better suited to small applications, even as small as laptop computer or cell phone batteries, and others work best as medium-sized power generators for houses or larger buildings. The best varieties for automotive use operate at relatively low temperatures, under 300 degrees fahrenheit. Other types operate at temperatures over 1,000 degrees F. A fuel reformer, which extracts hydrogen from a hydrocarbon fuel, can allow use of natural gas, gasoline, or other fuels, and one experimental type of fuel cell runs directly on methanol. ``Waste'' heat and water can be recovered and used for energy co-generation or even drinking water. Because there is no combustion, the fuel cell produces no pollutants. And they make virtually no noise. On the negative side, although costs have decreased remarkably in recent years, fuel cells are still expensive because of their use of precious metal catalysts and expensive polymer membranes or electrolytes. But where there is a will, there is a way, and economies of scale should further decrease costs as well.
The quiet operation of a fuel cell was demonstrated to me by a ride in Toyota's experimental hydrogen fuel cell-powered Highlander at Challenge Bibendum. Acceleration was on a par with the Prius hybrid, nothing to excite the race car crowd but plenty good enough for the real world. Interior noise levels made a Lexus seem noisy. And a Lexus is a very quiet car. Fuel cell luxury cars will redefine the genre.
The most interesting vehicle at Challenge Bibendum was GM's Hy Wire. Where other future-tech vehicles were wrapped in contemporary clothing, the Hy-Wire looked to be directly from the 25th Century. An outgrowth of the Autonomy concept vehicle, the Hy-Wire is also a concept vehicle. But it is a concept vehicle that runs.
New technologies seem to first emulate the ones they replace, and then take off in their own direction. The first automobiles looked like horse-drawn carriages without the horse, and most current hybrid and fuel cell vehicles look like today's cars and trucks. The Hy-Wire goes in its own very logical direction. All power and control systems are encased in the 11-inch thick ``skateboard'' chassis, leaving the entire vehicle footprint available for passenger and cargo use. With electric motors (powered by a hydrogen fuel cell) there is no need for a conventional transmission, and each wheel can have its own traction motor. The name ``Hy-Wire'' comes from both ``hydrogen'' and ``by-wire'' technology, and all controls are electronically (by-wire) activated with no mechanical connections. So there is no need for a conventional pedal-and-steering-wheel control setup. One aircraft-like yoke does it all.
How is it to drive? I had a chance to spend a few minutes finding out, and it was the strangest driving experience of my life. Considering that many concept vehicles, and most of the stranger and most outlandish ones, don't actually run at all, GM is to be commended for making a running prototype out of the Hy-Wire. But someone who has never driven before would make a better Hy-Wire driver than anyone with experience. The combination steering, throttle, and braking control was nothing like any car control I've ever experienced, and while throttle and brake response were good, the steer-by-wire steering was closer to a video game control than driving a real car, with no conventional feedback. Like all fuel cell vehicles, the Hy-Wire was extremely quiet, and space utilization was truly amazing. One advantage of the skateboard chassis is that the body and interior can be changed - if you need a minivan one day and a sedan the next, just change what needs to be changed on the same chassis. Ah, the fantasy joys of concept vehicles.... But there are some good concepts in the Hy-Wire, and GM is committed to building a production fuel cell vehicle by 2010. So, if you see a long, low, quiet projectile on the road in a few years, it might be from Detroit, not Mars or Area 51. It's going to be an interesting future.