Media post: Electric Turbocharging

There was a time when a turbocharged vehicle was considered exotic. Turbochargers, which can increase a car’s horsepower up to 60%, were installed only sports cars and race cars. Today, turbochargers are still used on performance cars but they have become popular in standard passenger cars too. The reasoning in this case is that the car companies can install smaller motors in their cars when a turbocharger is used. This is advantageous because smaller motors get better gas mileage and pollute less. There are various types of turbochargers available today, each designed to enhance engine performance in different ways. This evolution in turbocharger technology reflects the ongoing efforts to improve vehicle efficiency and power.

How they work

With help from the experts at Suburban Chrysler of Garden City, MI, a Dodge, Chrysler, Jeep, Ram dealer, we will explain how standard turbochargers work. Fact number one: all internal combustion engines generate powerful exhaust gases. What turbochargers do is harvest the energy of these exhaust gases and uses it to power a small turbine. This turbine, in turn, is used to pressurize outside air so it can be driven into the engine for combustion. If you take a look at a turbocharger, it looks like a small fan with blades at either end. One end spins via the exhaust gases and the other end blows air into the engine.

Despite decades of improvements, all turbochargers suffer from something called “turbo-lag.” Turbo-lag is the delay in response that occurs when a turbocharger kicks in. Here’s what’s going on: when you punch the throttle of a turbocharged car, it takes a few seconds for the turbo to spool up and start working. This can be quite annoying when you need to accelerate quickly, as race cars do. Engineers have improved turbochargers over the years but turbo-lag still is a problem. Bottom line: it’s hard to make a turbocharged engine deliver the immediate response of a naturally aspirated engine.

A solution

Instead of driving the turbo with exhaust gases, why not drive it with an electric motor? An electric motor can respond within 250 milliseconds to a push on the gas pedal, so there really isn’t any turbo lag. It seems like a perfect solution. The problem is that that this technology will be expensive at first. The electric motor to drive the turbo will have to be quite powerful and will probably need more than 12 volts to power it. This is a major issue for engineers because higher voltages will require special alternators, multiple batteries and heavy wiring.

Is anyone doing it?

Most of the major automobile manufacturers are looking into electric turbo technology but few are saying much of anything yet. Audi is an exception, however. Their new SQ7 TDI sedan is slated to have an electric turbocharger installed on the engine. To drive it, a special 48-volt electrical sub-system will be located in the trunk. The results are impressive: Audi says their sedan SQ7 TDI with a 429-hp 4.0L V-8 diesel can hit 62 MPH in 3.6 seconds. That’s a fast diesel.

The future of electric turbos

If the electric turbocharger concept works well, it should proliferate rapidly. The driving public is going to love the fact that there is no turbo-lag. Electric turbochargers are unlikely to be seen on economy cars anytime soon but we should see it becoming common on larger, luxury sedans.