Quote:
Originally Posted by NeilBlanchard
Their electric motor is probably 92-94% efficient ALL THE TIME. No need to warm it up, or maintain the right RPM.
Toyota had a chance to really up the ante - and they barely managed a tweak. The aero could be better, and they need to go big battery with plugin charging.
The Tesla Model S is about TWICE the efficiency as the Prius.
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The Prius accelerator is just that, it controls your rate of acceleration, this is quite different to a accelerator in an ICE or EV where it controls RPM. The ECU automatically maintains the most efficient RPM and load, more or less independent of your throttle position.
I couldn't disagree more on the plug in hybrid. Why carry around a big heavy battery that reduces the car's efficiency and makes it more expensive to buy and run? The point of a hybrid for me is to have just enough battery to maximise fuel savings, for me at least it's not common to have the battery full, I'd say Toyota have sized it right for 90% of users.
My old tech G2 Prius costs 5c/km with petrol costing $5+ a gallon. If we had $2 gallon like you guys that would be 2c/km, a G4 should be in the sub 2c/km range. Your figures show 3c/km for your EV use.
Well to wheel studies have shown that EV's and Hybrids are just about the same in terms of Co2 depending of course on the cleanness of the grid. Even so, you'd have to be pretty keen to bother plugging in a hybrid if you know it's going add around one third to your fuel bill.
The US grid is 90% efficient, your charger is 90% efficient, the batteries under charge are 80% efficient, the batteries under discharge are 80% efficient, the inverter is 90% efficient, and the motor is 80-90% efficient. As high as each of those number is, those small inefficiencies do add up. You get 37% based on those numbers.
Even if you use best case scenarios (these numbers don't exists outside a lab as inverters/chargers/motors are most efficient under load while batteries are least efficient under those loads) of 90%, 95%, 90%, 90%, 95%, 90%. The EV is only 60% efficient. The Prius ICE is 40% efficient but that doesn't include energy recaptured via braking.
The likes of Leaf, e-Golf and the various California specials are no better than a Prius. The Tesla is a big step forward, but it's a long way from being twice as efficient. If also costs three(?) times as much, so you could buy a lot of solar panels (or similar investments) to more than offset your inefficient Prius, Golf, Leaf etc.