Fuels of the future: Chase the dream but keep working on what you've got
2-pronged strategy pursues the hydrogen vision and keeps tweaking old reliable gasoline-burners
Can unglamorous gasoline and diesel engines be improved bit by bit to prosper in an era of costly petroleum? Or will automakers manage a Great Leap Forward by developing affordable fuel cells?
Actually, General Motors has adopted both strategies. In the short run, the automaker is pursuing continuous improvement — a kaizen approach, in which incremental improvements can add up to big gains in fuel economy.
In the long run, the company is betting on a Great Leap Forward with hydrogen-powered fuel cells and electric cars. Here are the gurus who are managing GM's twin powertrain strategies.
Later, we'll make some predictions about their likelihood of success.
Photo credit: JOE WILSSENS
The king of kaizen
The king of kaizen is Tom Stephens, group vice president of GM Powertrain. Although he concedes that electric motors eventually will prevail, he believes he can make gasoline and diesel engines vastly more efficient in the near future with a series of upgrades.
Stephens is tall, confident, down-to-earth — and a consummate gearhead. When he was a teenager, he dropped a Buick V-8 into a Chevrolet Vega. Today his pride and joy is a restored 1960s-era Chevrolet Impala convertible.
Perhaps because of his taste for classic Detroit metal, Stephens has proved willing to rehabilitate old technologies once derided as failures. An example: A few years ago, his engineers wanted to re-examine cylinder cutoff technology, which flamed out spectacularly on Cadillacs in the early 1980s.
He encouraged them. The new system works so well in GM's pickups that motorists often don't realize their engines are running on four cylinders.
While cylinder cutoff technology is a clever way to make V-8s more fuel-efficient, Stephens believes future internal combustion engines will be smaller and lighter.
Some will be paired with powerful electric motors powered by lithium ion batteries to form hybrid powertrains. Others will be outfitted with turbochargers, direct injection, adjustable valve timing and other features. And they will be more powerful than the engines they replace.
GM already has started to execute this strategy. Here are some key developments:
In 2010, the Chevrolet Volt plug-in hybrid goes on sale. With a small gasoline engine that recharges its lithium ion batteries, the Volt can achieve 50 mpg when the gasoline engine is running.
The Pontiac Solstice GXP is powered by a 2.0-liter, direct-injected turbocharged engine. The four-cylinder powerplant generates 260 hp, the highest output per liter of any production engine in the company's history.
With fuel economy in the mid-20s and 0-to-60 mph performance in 6 seconds, this engine is the template for GM's kaizen strategy.
Next year, the Chevy Silverado will get a 4.5-liter diesel V-8 that does away with the heavy cast-iron exhaust manifolds that have been bolted to cylinder heads for 100 years.
Instead of a bolt-on intake manifold, the new engine integrates the manifolds into the cylinder heads. The new engine weighs at least 60 pounds less than a conventional diesel, and it dramatically reduces manufacturing costs.
That's not all. GM engineers are developing a more efficient gasoline engine. It combines the best traits of gasoline and diesel engines: homogenous compression charge ignition, or HCCI.
Depending on the vehicle's speed, the engine runs like a diesel by using compression to ignite the fuel. Or it can run like a gasoline engine and use spark plugs to fire the cylinders.
This engine generates reduced emissions while delivering 15 percent better fuel economy. And it does so with none of a diesel's costly filters.
The system could be on the road in five years. But first GM engineers must pioneer new technology that measures in-cylinder pressure and temperature. "When you look at what it's going to take to make that happen," Stephens says. "I think it is only a matter of time."
For GM to improve fuel economy, it must produce these innovations cheaply enough for mass production. "I've got to do these things by the millions if I really want to make a difference," Stephens adds.
These are the kaizen improvements that can keep gasoline engines in the game.
Burns: Leading the Leapers
Meanwhile, down the hall, another research team is working feverishly — and spending heavily — to develop fuel cell vehicles for mass production.
The architect of GM's Great Leap Forward is Larry Burns, vice president of r&d.
The soft-spoken Burns has become GM's high-tech spokesman. He is easygoing and low-key, and often begins his presentations with a cheesy joke that tells audiences they're not dealing with someone who speaks only in equations.
At every opportunity, Burns evangelizes to audiences on the merits of his Great Leap Forward — a concept vehicle called the Chevrolet Sequel. The Sequel, introduced in 2005, is a fuel-cell powered vehicle with drive-by-wire technology.
The Sequel drives, feels and behaves like a typical car, even though it has no engine, transmission, hydraulic brakes or steering, rear axle or radiator.
Perhaps the only things that give it away are the noises that it makes. Press the accelerator and you'll hear the gentle hum of an electric motor and the whoosh of air being sucked through the grille and expelled out the back. The Sequel isn't some science class project; it's a real car with a range of 250 to 300 miles.
And the Sequel can achieve that range without sacrificing power steering, air conditioning or other features that consumers expect.
The Sequel shows GM has made impressive progress. There have been five generations of fuel cells, each one smaller, more powerful and less expensive. The latest fuel cell fits into the same space as GM's 2.3-liter Ecotec four-cylinder engine.
The biggest problem is cost. GM spent more than $1 million to build the Sequel. And over the past eight years or so, GM spent more than $1 billion on the technology that has gone into the Sequel.
All that money will be well spent if Burns can figure out how to produce a vehicle priced for the mass market. It's not at all clear whether that's possible.
But Burns believes the auto industry inevitably will adopt the innovations showcased by the Sequel. "I believe the future's going to be about electricity and hydrogen as opposed to petroleum," Burns said.
So which approach will look the best in the rearview mirror of, say, 2030?
Someday, electricity probably will displace fossil fuels and render the internal combustion engine obsolete. But that won't happen soon. Here's why:
Even if U.S. gasoline prices double, internal combustion engines are tough to beat in terms of efficiency, manufacturing costs and durability. After all, motorists still drive gasoline-powered vehicles in Germany, where the fuel currently costs $8 per gallon.
If any automaker wants to produce vehicles fueled by hydrogen, somebody must spend billions of dollars to create a nationwide network of refueling stations. Any volunteers?
GM's fuel cell cost must be reduced by a factor of five to make it competitive with a conventional engine.
Electric cars will need a daily range of 200 to 300 miles per charge. Even with lithium batteries, it's not at all clear whether that's possible.
And so the internal combustion engine — albeit much more efficient and electrified than what GM is building today — seems likely to power most of GM's cars and trucks for the next 20 years.
Kaizen may not be glamorous, but it works.