World's Fastest Hybrid OK'd For Production 208
Posted
by
timothy
from the probably-can't-use-the-hov-lanes-though dept.
from the probably-can't-use-the-hov-lanes-though dept.
thecarchik writes "The Porsche 918 Spyder hybrid supercar, first shown as a concept at this spring's Geneva Motor Show, got official approval as a production model today from the company's board of directors. Just consider the specs: a 500-horsepower, 3.6-liter V-8 engine with a 9200-rpm redline, 0-to-62-mph acceleration of 3.2 seconds, and top speed of 198 miles per hour. Oh, and did we mention it gets 78 miles per gallon on the European cycle? The astounding fuel efficiency comes courtesy of an E-Drive mode that lets the 918 Spyder drive up to 16 miles on pure electric power, though [ahem] not at 198 mph."
Tesla (Score:1, Insightful)
Deceiving. (Score:5, Insightful)
"78 miles per gallon on the European cycle"
Sure, and my plug in golf car gets mpg on any test thrown at it. Really that's poor and deceitful advertising. This car is a plug in car - it doesn't generate it's own electricity. It's not like a prius where you just fill it and forget about it, you're supplying another form of energy yourself. Saying what MPG it gets is redundant unless you also show how many Joules of electricity it used in the process as well.
What am I missing? (Score:2, Insightful)
The other modes (Hybrid, Sport Hybrid, and Race Hybrid) sound interesting, but consider:
Ahhh, who cares - just park one in my driveway, and let me do an in-depth product test!
Re:SI units (Score:3, Insightful)
\ How many Joules are used by an electric car? Which losses are we including (transmission, storage, motor efficiency)?
I'm seriously asking, because I'm not sure a Joules to Joules comparison would necessarily be any more helpful.
Re:Tesla (Score:2, Insightful)
Comparing a 155K car to a 61K car isn't exactly fair...
Re:Deceiving. (Score:5, Insightful)
Or, for the idiotic mass public:
"Miles per buck"
Really, that's all people care about. Multiply by the average cost of a gallon of fuel, or kwh of charge, and spit out a number any cousin-fucking retard can understand. Maybe then people will become a tiny bit more conscious about efficiency, and/or take arms against the energy cartels (a nerd can dream, can't he ?)
Re:Tesla (Score:3, Insightful)
It's called flashblock, use it.
Re:And this one pays for itself... (Score:4, Insightful)
Re:Deceiving. (Score:3, Insightful)
Subtraction is just addition using negative numbers. Why not skip subtraction altogether and just do addition? And hey, multiplication is just addition done over and over, and division is just subtraction done over and over, so we could simplify all those operators down to just one.
We don't do that, not because we're too stupid, but because it's terribly inconvenient to work everything out in terms of addition alone. We pick the notation that's most convenient for the given purpose.
Doing the faction in terms of volume-over-distance is better in comparing fuel efficiency because it makes it obvious where to focus efforts in efficiency increases.
Full writeup on the subject [greencarreports.com].
Re:And this one pays for itself... (Score:3, Insightful)
Give them credit (Score:2, Insightful)
Missing the point (Score:2, Insightful)
A lot of comments here miss the point of this car.
It recovers some of the braking energy before a corner to charge the batteries, and then use the electric motors to exit the corner faster. The point of this car is to go fast, not save fuel/money (seriously guys a $500,000 car to save money?)
The fact that you can use it as a hybrid and get good mileage in some (very rare) circumstances is no more than a funny side effect.
Re:Question for car engineers (Score:2, Insightful)
It's true that an electric motor provides more torque than an internal combustion engine at low revs.
The shape of the toque curve is very different.
An electric motor can provide a lot of torque at 0 rpm, while an internal combustion engine can't even keep itself turning at very low revs.
This means that the power curve has a different shape. An electric motor has a much broader curve, so it is able to run with high power over a large range of speeds. So much so that it wont need a clutch, and may not need different gear ratios. It may still need some kind of gearbox to match the rpm of the motor to that of the wheels, but a single speed box is sufficient in many cases (possibly not if you want to get the max possible performance).
Wide tires dont give you extra contact area. The area of contact between the tyre and the road is determined mostly by the air pressure in the tyre. If you increase the width of the tyre without changing the pressure then you change the shape of the contact patch, but not its area (not much anyway). Wide tyres are useful because they are less affected by irregularities in the road surface and because they spread the load through a large area of rubber (so they dont overheat so quickly). The contact patch is also short and wide, which means that the front and rear edges of the contact patch are longer (and these edges carry a bit more of the load than the centre due to the bending of the rubber). An Ultra-wide (steamroller) tyre would not be useful. It would require some internal structure to transfer weight to the centre of the tyre (otherwise it would bend and just lie on the road surface in the middle with very little pressure). It would also cause cornering problems - how would you provide a differential? Wide tyres already have problems cornering due to the difference in road speed between the inside and outside edges - there is bound to be some slippage. Narrower tyres are usually more efficient. The only practical way to increase traction is to provide extra downforce (e.g. aerodynamic - which only works at speed) or to use all 4 wheels for traction (doing something to the materials of the tyre/road and the tread pattern also have some effect).
Re:Wow! (Score:4, Insightful)
The loan Is a subsidy. If it wasn't, they'd have to get the loan on their own, and they'd be paying more for the money (e.g. interest). Otherwise they wouldn't have bothered getting it from the government.