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Commentary By Peter W. Huber

The Silicon Car

Energy Technology

We love the web, but we still vacation in Tuscany. Most of our time, effort and resources go into moving the solid, not the virtual, things of life. And most of the moving is still orchestrated by click-click, bang-bang mechanical and hydraulic systems. The intelligence, such as it is, resides in valves, gears and complex contours painstakingly machined into camshafts.

Silicon is now rapidly taking over. The key technology coming of age is the electric servomotor—one with a very fast and intelligent feedback loop. Such motors can move a shaft very precisely, along any trajectory you define. They can be small enough to move a silicon wafer through a chip fab, or big enough to move a forklift.

The one catch: It takes extremely fast and accurate control of their current supply to make them behave. And that's what has recently become possible. Combine silicon in microprocessors—smart chips—with silicon in solid-state electric power switches—power chips—and you can make a heavy-duty electric motor as disciplined and nimble as a ballerina.

It's happening now under the hood of the car. Think of a 130-horsepower Buick as a 100-kilowatt (peak power) toaster, except that only two kilowatts (peak) of its power are electric today, the rest being all shafts, belts and hydraulics. Drive-by-wire electric power steering will appear in some production vehicles within a couple of years. All-electric brakes will emerge in tandem. Passive springs and shock absorbers will give way to powerful linear motors that move wheels vertically as needed to maintain traction beneath and a smooth ride above. Electric valves will replace mechanical ones on the cylinder head. In the end electric drives will turn the wheels, knocking out the gearbox, driveshaft and differential.

The linchpin: an integrated starter motor/alternator interface between the engine and the car's electrical grid, to convert more (and eventually all) the horsepower into kilowatts. Such units will begin infiltrating the engine within the next few years. Why bother? Electric drives are lighter and smaller—a 50mm-diameter electric cable can convey as much power as all four engines of a jumbo jet. They're also faster and more responsive—mechanical systems respond at the speed of sound; electrical ones, at the speed of light.

The payoffs are tremendous—think electric wristwatch versus mechanical. Torque, traction, braking, skid control, fuel economy and emissions all depend on the complex interaction of engine, battery, suspension, steering and brakes; the magic lies in the intelligent coordination of all the parts, which silicon makes possible. The improvements compound with each additional smart "client" added to the carwide electric web. And the car sheds hundreds of kilos, as well.

So why didn't Henry Ford and Thomas Edison get together to build the Model T that way? They lacked the silicon. Without really smart and very fast control, electric drives are jittery and unstable; they're good only for simple and steady operations like continuously spinning a shaft. Hair-trigger response is useful, it turns out, only in the very steadiest of hands.

Which you get when you combine the smart chips and power chips together in the same box. Recently developed, fingernail-size Mosfet power chips can switch hundreds of watts at microsecond speeds. An array of such chips feeding a servomotor under the oversight of a Pentium chip can actuate valves, steer, brake and drive wheels precisely enough to deliver the kids safely to the soccer field.

Or the F-16, nuclear submarine, diesel-electric locomotive, monster truck or industrial robot to wherever it happens to be headed. Silicon-electric drives have already moved deep into those platforms. But in the atom-moving business, Detroit is much bigger than all the rest. That's where the costs really plummet and the technology takes off. Cars will do to direct drives what the desktop did to computers.

Most of the "electric car" hype has centered on fuel cells and the primary power plant. That gets things exactly backward. For the next decade, at least, it isn't the combustion engine that will be displaced. It's what's downstream.

This piece originally appeared in Forbes

This piece originally appeared in Forbes