The Way To Save Fuel Is To Make a Better Computer?

Toyota has announced a new way to improve fuel use by 10 percent for its hybrid vehicles. Instead of some sort of new powertrain or transmission, however, the high-tech solution has more to do with electronics than horsepower or fuel injectors.

You might know that hybrids get their big fuel savings by relying on a large battery instead of gasoline. It’s what lets them start up and zoom away with eerie quietness—the battery then famously recharges when you hit the brakes and the energy is captured.

But how does the car know how to do all that? The answer is computers, specifically a Power Control Unit, or PCU. The PCU is built from semiconductors, boards of electronic material that you’ll find in everything from wristwatches to alarm clocks to computers and smartphones. Semiconductors are great at managing the flow of electricity, and electricity is exactly what makes hybrid vehicles so great.

Toyota’s addition is to use a new material in the construction of those semiconductors. Instead of using pure silicon, Toyota has figured out a way to use silicon and carbon. The result of this arrangement limits electricity loss that happens in today’s pure silicon system. So basically, more fuel will be saved by using a nerdy material inside a computer system that no one even knows or cares about. Neat, huh?

Okay, okay, so most people will only register that MPGs will be slightly higher than they were last year. This advance, however, will also let more models use hybrid systems. So instead of just the Prius and Camry being the only ones affected, we could see fuel efficiency go up for Toyota vehicles across the board. Better overall efficiency gives Toyota more wiggle room to let its performance vehicles use gasoline more liberally, so in a paradoxical way, bettering hybrids could mean more robust roadsters. We’ll see.

Silicon, left, and silicon-carbide.