Six car technologies that will help you go the extra mile
“By 2025, we believe most vehicles will still be driven by internal combustion engines [ICE] and the traditional ICE still has major potential to further reduce emissions,” said Enno Tang, head of chassis and safety technology at Continental, at the 2016 Global Automotive Forum in Chongqing.
Despite US President Donald Trump’s March 15 announcement of a review of fuel efficiency standards, there is a move worldwide, prompted by regulation and consumer demand, to get more mileage out of engines.
The future may be electric. China has proposed that manufacturers need to gain an 8 per cent credit score from new energy vehicles from next year. Sales, however, are simply not approaching the kind of levels required to hit that score. There are few countries – Norway being one exception – where EVs account for a large proportion of car sales.
Here are some new technologies that are either coming soon or are already on the market, which promise to go the extra mile for you.
Homogeneous charge compression ignition (HCCI)
Mazda’s next-generation SkyActiv petrol engine ditches the spark plug for use of HCCI technology. Set to debut next year in the new Mazda 3, it uses pressure to burn the fuel-air mixture rather than igniting it using a spark plug, much in the same way as a diesel engine.
This promises diesel-like fuel economy in a petrol engine and allows the compression ratio to increase. A compression ratio is the difference between the volume of the cylinder at both extremes of the piston motion and is typically between 10:1 and 12:1. Thermal efficiency increases at high ratios but normally comes with increased knocking – abnormal combustion of the fuel/air mix.
Current generation SkyActiv engines have increased the ratio to 14:1 but use of HCCI promises an increase to 18:1. This gives a 30 per cent reduction in fuel usage over a non-SkyActiv engine. Mazda has chosen to invest in eking out improvements in ICEs while EV technology matures.
At the 2016 Guangzhou Auto Show, Qoros displayed its QamFree. On a normal engine the camshaft controls the opening and closing of the inlet and exhaust valves of each cylinder. In the QamFree engine the camshaft is replaced by a PHEA. This allows independent control of every valve and means that intake and exhaust of each cylinder can be more precisely controlled. It also allows for cylinders to be switched off when, for example, cruising.
Laboratory results claim a 47 per cent increase in power, a 45 per cent increase in torque and a 15 per cent fuel reduction. The technology was developed by Koenigsegg, and Qoros is currently testing it in three cars using a modified version of its 1.6T engine. The increased power should allow fitting of smaller displacement engines, and the size and weight reduction due to eliminating the camshaft may also increase efficiency potential.
Variable compression turbo (VC-T)
Infiniti’s VC-T engine should be launched on the market next year. A high compression ratio, as with Mazda’s SkyActiv, favours fuel efficiency whereas a low ratio is better for performance. The new Infiniti engine allows the best of both worlds, giving a variable ratio of between 8:1 and 14:1 by use of a multi-link system to adjust the ratio according to driving conditions and driver inputs.
The 2-litre unit under development aims for power output of 200kW (268hp), and 390Nm torque while delivering a 27 per cent fuel reduction over a V6 engine of similar power.
Kinetic energy recovery system (KERS)
This technology, originally developed for Formula One racing, recovers energy usually lost as heat under braking. Torotrak’s Flybrid system stores this in a flywheel rather than in a battery, as in a more conventional hybrid system. Compared to a battery based system it is about a third of the weight and avoids energy loss in conversion from mechanical to electrical energy and back.
Cost is also about a third of an electrical system, meaning much quicker payback, and it can be easily incorporated into existing engines. A Volvo S60 fitted with the system achieved fuel savings of up to 25 per cent.
Torotrak also offer a variable drive supercharger known as V-Charge, which aims to eliminate the turbo lag associated with some of the new, smaller forced-induction engines. This, it’s claimed, will help more widespread uptake of engines such as three-cylinder, 1-litre turbos replacing four-cylinder, 1.6-litre engines.
48V mild hybrid
This again recovers energy otherwise lost under braking but stores it in batteries using a 48V system. On systems developed by companies such as Bosch and Getrag, the motor generator is integrated into the transmission. This has advantages over existing mild hybrids in that it can allow all electric driving at low speeds rather than the current electric assistance.
These systems typically provide about 15kW of power and 150Nm of torque. Fuel savings are in the region of 10 per cent to 15 per cent.
Low rolling resistance tyres
Tyres account for 20 per cent of fuel consumption in cars and 30 per cent with lorries. If you look at the tyres of a Formula One racing car, they are almost smooth in order to minimise resistance as much as possible. For normal drivers, though, having enough grip to stay on the road is pretty important and there are legal requirements for minimum depth of tread.
Low rolling resistance tyres appeared in the ‘90s but early ones came with significantly reduced braking performance. The latest generation, such as Michelin’s Energy Saver+, have solved the problems. Rolling resistance is down by 20 per cent and the EU, which gives energy labelling to tyres, believes such tyres can provide fuel savings of up to 9 per cent. This is achieved by limiting heat build-up and by having an inner layer of polymers under the tread, which improves rolling resistance. It is also a technology that can easily be fitted to existing cars.