Pumped up: Why gasoline engines are here to stay

From Thursday's Globe and Mail

January 29, 2009 at 12:00 AM EST

Plans to develop electric cars, plug-in hybrid cars, fuel-cell cars, super-clean diesels, perhaps diesel hybrids and other exotic technologies — impressive and far-sighted as they are — are overshadowing the very real but less exotic steps the industry is taking to improve fuel economy and reduce emissions right now.

By "now," we are talking about the next 10-20 years. During that time, the internal combustion engine will keep dominating the automobile world. Exotic technologies are interesting, but the reality is that nothing is ready to unseat the gasoline-powered internal combustion engine.
On the contrary, the auto industry keeps finding ways to squeeze more efficiency out of gasoline engines.

Take the upcoming 2010 Chevrolet Cruze compact car. The Cruze, about the size of a Ford Focus or a Toyota Corolla, but roomier inside than both, will have one of the smallest engines on the market. Yet the 1.4-litre turbo will deliver the performance of a larger engine with fuel economy of 40 miles a gallon (U.S.) or about 5.9 litres/100 km.

More developments and refinements of this sort are coming, and soon, too. Auto makers are working on "twin charging," for instance. That uses two turbochargers or a turbocharger paired with a supercharger, to get more power and greater fuel efficiency out of smaller motors.
In fact, GM, Ford, and others, are launching big initiatives that involve tweaking internal-combustion engines with turbochargers and a technology called gasoline direct-injection. Their goal: make fuel-stingy small engines perform like big ones.

Ford's Derrick Kuzak, the head of all product development at the company, says his company's EcoBoost technology makes smaller engines perform like bigger ones, with no fuel economy penalty.

With EcoBoost, Ford uses turbochargers and direct injection to cut fuel consumption by up to 20 per cent and limit greenhouse gas emissions without any loss of performance.
"We are going to have 500,000 vehicles in the next five years that will have this technology," says Kuzak.

Direct injection makes fuel burn more efficiently by squirting it straight into the combustion chamber, instead of mixing it with air in an intake port.

Turbos are tiny windmills spun by otherwise-wasted exhaust. The turbo runs a compressor that pushes air into the combustion chamber where it mixes with fuel. The enhanced air/fuel mixture develops more power without a large fuel economy penalty.

EcoBoost will make its debut in the Lincoln MKS later this year. Its twin-turbo, 3.5-litre V-6 will have 340 horsepower. That's the horsepower equivalent of a V-8. By 2013, Ford says it will offer EcoBoost engines on 90 per cent of its models.

At GM, direct-injected, turbocharged engines are already sweeping through the automaker's lineup. The 2.0-litre, 260-horsepower, four-cylinder engine in the Pontiac Solstice and Saturn Sky sports cars has this technology. The same engine is in the SS version of the Chevrolet HHR small sport utility and the Chevy Cobalt SS.

At Mazda, the CX-7 crossover has the same 2.3-litre, turbocharged, four-cylinder engine with direct gasoline injection as the high-performance MazdaSpeed3. A 2.0-litre, turbocharged, four-cylinder with direct gasoline injection powers the Audi A3 five-door hatchback, A4 sedan and TT sports car.

Boosting engine performance with turbos and direct injection is a common-sense way to increase fuel economy. A gas engine modified in this way can grab a 20-per-cent fuel economy gain, while hybrids typically deliver a 30 per cent fuel savings, depending on the mode.

What really stands out, though, is the cost. Adding direct injection and turbocharging to an internal-combustion engine typically costs an auto maker about $1,000 (U.S.) per vehicle.
By comparison, the cost premium for a clean-diesel engine is at least $3,000, if not more, and gas-electric hybrid technology adds at least $4,000 to the cost of producing a vehicle (all figures in U.S. dollars).

The wild card in determining which technology makes the most sense: the price of fuel. In the last year, for instance, it's been all over the map, with oil closing in on $150 a barrel last year, only to fall to less than $40 a barrel recently.

Unpredictable fuel prices make it tough to make firm predictions, but Kuzak estimates that if oil goes back up to the levels seen last summer, the EcoBoost system will pay for itself in gas savings in less than three years for drivers who log about 24,000 km a year.

Some estimate a seven-year payback for diesel engines and 11-12 years for hybrids, though the cost of diesel engines and hybrids are coming down and, again, fuel prices are unpredictable.
Beyond engines, manufacturers are ratcheting up the number of gears in transmission to boost fuel economy. It is now common to see five- and six-speed automatic transmissions in even the most affordable vehicles.

Luxury makers have gone further by putting seven- and eight-speed automatics into their top-of-the-line cars. Mass-market vehicles are next to get those automatics.
Other new fuel-saving transmissions include the twin clutch and the continuously variable transmission (CVT). The CVT improves fuel economy by 5 per cent or so over a more traditional automatic.

At the same time, auto companies and suppliers are making real gains in improving fuel economy with better electronic controls and electrical (rather than mechanical) systems to help reduce fuel consumption and vehicle emissions.

For instance, Hyundai's new 2009 Elantra Touring has a base price of less than $15,000, yet it has electric power steering that eliminates the engine pumping losses that dog hydraulic power steering systems. The fuel economy gain is not great, perhaps 1-2 per cent, but it's very real. Most new models now come with electric power steering, regardless of vehicle price.
Auto makers and their suppliers are also rolling out other off-the-shelf technologies that help vehicles gain a little fuel efficiency here, a little there.

Take low-rolling-resistance tires. They use different tread patterns and additional silica in the tread to reduce the fuel-consuming forces that work on tires: air or wind resistance, inertia when accelerating, gravity when driving uphill, internal friction, for instance, in the transmission and the general rolling resistance that occurs when the rubber hits the road.

Then there is the stop-start system. It automatically turns the engine off when a vehicle stops, then restarts the engine when the driver takes his foot off the brake. A stop-start feature can produce a 5-per-cent fuel saving by essentially eliminating idling.

The Mini Cooper sold in Europe offers stop-start and it is expected to make its way to Canada in the future. Mazda is likely to offer stop-start next year on some models.

Meanwhile, cylinder deactivation systems have been around for years. They shut down some cylinders when they are not needed by stopping the flow of fuel to those cylinders. So, eight- and six-cylinder engines can operate in a four-cylinder mode, for instance.

GM, Chrysler and Honda have all pushed this technology into mainstream vehicles such as the Chevy Impala and Honda Pilot. The fuel saving is estimated at about 7 per cent.

Then there is continuously variable valve timing. This technology fine-tunes the operation of valves that control the flow of air and fuel into the cylinders. When and how long the valves open (timing), and how much the values move (lift), affect engine efficiency.

By optimizing timing and lift settings for high and low engine speeds, it is possible to get as much as a 5-per-cent fuel saving. Almost every new engine introduced these days has variable valve timing.

Auto makers also are refining vehicle designs to maximize aerodynamics, thus cutting down on wind resistance and improving fuel economy.

Finally, lighter materials such as plastic and aluminum are replacing heavier steel components to reduce vehicle weight.

All these enhancements and others do not require a massive retooling of auto manufacturing and supplier factories, and they do not need a massive overhaul of our refuelling infrastructure.
None requires rethinking the electric grid, or building battery recharging stations or battery swap centres. None presents the challenge of being supported by a hydrogen refuelling infrastructure. And all these technologies are do-able and affordable.

It's great to dream big, to imagine electric cars, plug-in hybrids, fuel cell cars and the like, but today's reality is less gaudy and eminently practical.

The silver bullet on fuel economy and emissions is not a bullet at all, but a lot of little shotgun pellets that together hit their target to make cars more efficient, less thirsty and less dirty.