Nothing says better what I think about the Toyota Prius than "I hate the Toyota Prius", either in English or Tagalog. And while somebody can think I'm "just a hater", there are reasons to hate the Prius.
It doesn't exploit the main advantage of the electric drive: reversibility, then no gearbox would be required for the electric motor. Or do we use a gearbox for our home cooling fans? Clearly not...
I don't understand why Toyota, so acclaimed and laureate, could make a hybrid like that. Instead of bolt the internal-combustion engine and the electric motor on the same gearbox, could benefit the handling and the efficiency using either a single motor bolted to a pair of half-shafts on the rear axle, or one in-wheel hub motor on each rear wheel. Even the extra weight from these setups could compensate the improvements over the efficiency on electric drive mode. Also, it would get 4-wheel drive ability, great for our hilly terrain in the Philippines, or even in Japan. Not to consider the notorious advantages to drive it in the rigorous Japanese winter and its snow.
Another problem: the traction battery packs. Not so easy to recycle Nickel metallic hydride, and an expensive proccess. The lifespan of a battery pack is often ignored by its owners and enthusiasts, who forgot the problems of heavy metals contamination on water, from the oceans to the underground water reserves. If it had a more efficient electric drive setup, the batteries could be smaller, then lighter, not sacrificing the range, at least reducing its environmental issue.
Another thing that just makes me mad is the lack of a diesel engine. If the intention is to get an eco-friendly vehicle, the most efficient thermodynamical cycle is still the Diesel cycle. And since it doesn't have an electric ignition there are less wasteful parts to be prone to fail and need replacement. Diesel engine blocks are usually stronger too, and lube oil usually has a longer lifespan. They're also easier to run on alternative liquid fuels, such as biodiesel, vegetable oils or even the nowadays acclaimed ethanol. Gaseous fuels would demand an assisted ignition, either from a spark system or a pilot-injection of a liquid fuel to be compression-ignited, and are also harder (and unsafer) to handle. But if you want to retrofit your Prius to run on a gaseous fuel, you can't do it: due to its "Atkinson-cycle", with the inlet valves timing setted to leave them open longer, intending to reduce the "pumping losses", backfire would be unavoidable, except if a supercharger was fitted to force the air/fuel mix back into the cylinders.
Just to compare:
1.8 Hybrid Synergy Drive: 99HP (134HP U.S.-spec)@5200RPM/142Nm@4000RPM + 82HP/207Nm from electric motor = 181HP/349Nm (216HP U.S.-spec)
1.4 D4-D: 90HP@3800RPM/205Nm@1800-2800RPM - with electric auxiliary drive would reach 172HP/412Nm, but the lesser 9HP wouldn't be noticeable at all...
2.0 D4-D: 127HP@3600RPM/309Nm@2400RPM - would get 209HP/516Nm with the electric setup
2.2 D4-D: 177HP@3600RPM/400Nm@2000-2800RPM - would not need auxiliary electric drive to superate the stock Prius Hybrid Synergy Drive setup, and not carrying the weight of the electric setup. And the 4HP difference would never be noticed, but if the electric setup came along it could reach 259HP and outstanding 607Nm.
To the karaniwan tao, the 1.4L D4-D meets all the needs, and being a Diesel it already goes more efficient than the hybrid setup. And it doesn't carry all that heavy electric driveline...
3 comments:
Do we use a gearbox for our home cooling fans? LMAO man, but you're right. Peugeot used the electric motor bolted directly to a rear differential in their hybrid version of the Peugeot 3008, that runs on diesel. Chrysler used a similar setup in the early Pacifica concept, with an electric motor driving the front wheels. Porsche is now going to use front hub-motors in one of their supercars to get AWD.
The 1.4L diesel would be a good powerplant instead of the spark-ignited Atkinson. Enought power and torque to a compact family car and due to the lesser weight and space taken by battery could have improvements on luggage space.
The Prius is not badly-shaped, but its aerodynamic design could be better enjoyed with a biodiesel-fired engine. Even retaining its electric drive assistence, but since it's intended to be a high-efficiency vehicle it should spot a diesel engine.
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