The internal-combustion engine has been the go-to choice for automotive propulsion for over a century, but with cars powered by electricity becoming more popular, their days of dominance are numbered.
Despite the many advantages of electric powertrains, dethroning the internal-combustion engines won’t happen anytime soon, and that’s because internal-combustion engines are solid and the best they’ve ever been, offering high power, practicality and low coste.
Car manufacturers are also under great government and market pressures to make their engines more environmentally friendly and fuel efficient, prompting them to develop a number of new engine technologies. Let’s have a look at some…
Turn Off the Power Accessories
With most of today’s engines use a rubber belt that runs off them to mechanically drive alternators, power steering pumps, water pumps, AC compressors and other accessories. However, it isn’t really necessary for these accessories to be running all the time.
Take your AC compressor, for example. Does it make sense for it use any power at all during winter? An obvious solution would be to drive the accessories through electric motors that could be shut off when needed.
These accessories could be electrically driven, but the 12V electrical system in cars today just wouldn’t be able to deliver the power needed to so. One way to overcome this problem is to step up the voltage for more efficiency, and there have been proposals for 48V systems with more efficient electric motors that could be shut off when not needed.
Systems such as this will eliminate inefficiencies and this may yield gas mileage increases of some 10-15%. We are told that Volvo is about to release several models with 48 Volt systems. According to Kims No Bull of Laurel, a local Chrysler, Dodge, Chevrolet, Nissan, Ram, Toyota dealer in Laurel, MS, Toyota will offer an electric supercharger on their 2018 Supra model and this will require the car to be wired for 48 Volts.
Shut Down Cylinders
The concept of cylinder deactivation isn’t new. In 1981, Cadillac introduced cylinder deactivation on its V-8 engines, with the intention of allowing them to save gasoline by automatically switching off two or four cylinders.
It was a good effort by Cadillac, but the company implementation of the technology wasn’t done very well and its system was considered a major failure.
The automotive engineers of today have almost perfected cylinder deactivation, delivering sophisticated systems that allow V-6 and V-8 engines to reliably cruise on just two of their cylinders. It is estimated that the latest advancements could cut down fuel consumption by as much as 20 percent.
Eliminate Timing Belts and Camshafts
Internal combustion engines utilize intake valves to draw in fuel and air into their cylinders and exhaust valves to blow exhaust gases out. Intake and exhaust valves have been actuated by camshafts for over a century, but as effective as this technique has been, change is in the air.
Several manufacturers are working on electric solenoids to open/close engine valves for two reasons: 1) it takes far less energy for a solenoid to open and close a valve than a camshaft requires. 2) engineers can fine tune the opening and closing timing to match engine loads and speeds more accurately.
While research is quite promising, it’s looking like this technology is going to require the 48 volt systems that we discussed before. It will be a few years before we see it in action