As the latest generation of hypercars have proven, electrification can do more for a car than just lower its emissions; it can make it faster too. But while the McLaren P1, LaFerrari and Porsche 918 Spyder are beyond the means of most, Audi is working on a new car that uses electricity to boost performance too.
The RS 5 TDI concept features a 3.0-litre V6 bi-turbo diesel engine with an electric turbocharger replacing the smaller turbo for quicker acceleration. CompleteCar.ie drove a prototype with this technology a couple of years ago and we were impressed with the instantaneous nature of the electric turbo, but Audi has continued to tinker with the idea since then with the result being that, not only can the RS 5 TDI concept complete the 0-100km/h sprint in just four seconds, but power from the bi-turbo V6 engine has also jumped from 313- to 385hp, and it's backed up with 750Nm of torque.
"25 years ago, Audi launched the first TDI on the market, writing the first chapter of an enduring success story," says Prof. Dr. Ulrich Hackenberg, Board Member for Technical Development. "Our latest innovation is the electric turbocharger, which further improves not just sprint times and pulling power, but also efficiency. This technology illustrates the possibilities harbored by 48-volt electrical systems, which we are currently developing for use in production vehicles."
The 48-volt electrical system is what powers the electric turbo and it does so via a small lithium-ion battery that draws its power from the car's recuperation systems such as regenerative braking. When deployed, the compressor in the turbo spins to over 70,000rpm within a few hundredths of a second, giving the RS 5 TDI its impressive acceleration. The new set up also allows for the fitment of a larger, second stage mechanical turbo, which produces as much as 2.4 bar of boost at maximum power. This helps achieve a top speed of 280km/h.
Anything else?
The RS 5 TDI is not just quick, but also efficient - more so than any other to wear the RS badge so far. The average fuel consumption is less than 5.3 litres/100km with emissions below the 140g/km mark.