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Plug-in Hybrids May Not Go Mainstream, Toyota Says
mattnyc99 writes "Honda's challenger to the Prius — the Insight hybrid that we discussed so lividly a month ago — got its official unveiling today at the Paris auto show, with insiders confirming it would be cheaper than the world's most popular 'green' car while still hitting the same fuel-efficiency range. But the hybrid-electric showdown comes in the midst of a sudden rethink by Toyota about plug-in hybrids. Apparently all the recent hype — over the production version of the Chevy Volt, plus Chrysler's new electric trio and even the cool new Pininfarina EV also unveiled today — has execs from the world's number one automaker, and alt-fuel experts, questioning how many people will really buy electric cars, whether people will really charge them at night to keep the grid clear, whether batteries will make them too expensive and more. "
Plug in hybrids still use gas. That's why they are hybrids, otherwise they would simply be electric cars.
The idea here is to juice up the batteries at home and use them for the first x number of miles (hopefully enough to handle your commute). After that, when the batteries are low, a small diesel (or gas) engine will start up and begin charging the batteries providing you with more range. So if your out of juice you would simply fill up just like a regular car.
Of course I'm curious how they will report the millage on these cars. I would want to know the range on the electric system and the millage when running purely on gas, but I worry they will come up with some new way to measure it that has little to no meaning.
"In America, first you get the sugar, then you get the power, then you get the women..." -H. Simpson
I ordered an electric vehicle, and am building another one from scratch. To charge them, I built a charge controller that fetches the current price of power from my utility, and only charges the vehicles when the price of power is below a threshold. This way I take advantage of Time Of Day pricing (1-2 cents/kwH between midnight and 4am, Nuclear power in Northern Illinois).
The volt has a charge timer built into the car's charging system. Set the timer once, and plug the car in any time. It will start charging (and/or stop charging) when you specify.
Around the turn of the century, electric cars had a range of about forty miles... the same as the Chevy Volt. All the improvements in battery technology have been able to do no more than keep up with our expectations of automotive comfort and speed.
Electric cars have, for a century, been waiting for the big breakthrough in battery technology that has yet to occur. The brilliance of the basic TRW design--the one they could never get U. S. carmakers interested in, the design that is fundamentally the same that Toyota uses in the Prius--is that it only relies on the battery as a short-term buffering device, a "torquer" as TRW called it, to make up the difference between the torque that can be provided by a little economical gas engine and the torque that's needed in normal driving.
So, a Prius provides a very meaningful increase in fuel efficiency without demanding a battery made of unobtainium. The Prius battery in fact only stores about enough energy to drive the car for about a mile.
Despite the possibility that Toyota is putting a spin on things, what they are saying makes sense. As hobbyists have confirmed, a Prius is virtually ready to be a plug-in hybrid, needing only a bigger battery. It would seemingly be so easy for Toyota to compete in the plug-in hybrid market that I have to believe they have sound reasons for skepticism.
Another possibility is that Toyota has encountered some serious snags that they're not talking about in trying to produce a plug-in version of the Prius. Perhaps GM knows about these snags and has some trade-secret ways of overcoming them... or perhaps GM hasn't discovered them yet, or is ignoring them because the Volt isn't really intended to succeed and is just a very elaborate "image" ploy.
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For any kind of sizable battery, you'd likely want a dedicated circuit anyway.
The current Prius battery is about 1.5KWhrs, so assuming a dedicated 100-120V 15A circuit, it would take about an hour to charge from dead to full, but that will only get you a few miles on pure battery.
The current plug in modification kit's battery is about 6KWhr, so 4x the time.
Sources I see on the factory plug in say a capacity between 6 and 12KWhr, and a 12 would require a full 8 hours to charge, which is getting to the limit of "charge overnight", so you might want to put in a dedicated 240V 20A circuit, like you would use for an electric range.
And you'd definitely need a dedicated circuit for a full EV, like the Tesla, as the battery pack is 53KWhr, which would take about 35 hours to charge on a dedicated normal circuit, and still 7.5 hours on a dedicated 220V plug.
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Wind farms don't scale
They do. http://news-service.stanford.edu/news/2007/december5/windfarm-120507.html
Yes, I'm left. You have a problem with that?
The Chevy Volt seems to be using two basic metrics.
1. How far you can run on fully charge batteries (40 miles)
2. MPG when the generator kicks in (50 MPG)
The Chevy Volt uses an IC engine to recharge the battery when necessary - like all other hybrids (though Chevy calls it a "range extender").
Calling the car an electric w/range extender, rather than simply hybrid (or series-hybrid) is marketing speak.
I don't think that's fair. In all other hybrids (on the market in the US today), the ICE is connected to the transmission and provides power to the wheels directly, in concert with the battery. They will use the battery and ICE proportionally to drive the car based on the speed. At highway speeds, they only use the ICE to drive and don't use the batteries at all. The range of most hybrids on pure electric power would be very small, and is really only the case when accelerating from a stop. On any normal daily commute of even a short distance, you're burning gas.
The big difference in the volt, whether you call it "electric w/ range extender" or "series hybrid", is that the ICE is not connected to the drive train at all. It is nothing but a gas generator to recharge the battery. Thus why I think it's fair to call it an electric car, because the motor is in fact pure electric, and the fact that so long as the battery has sufficient charge, the ICE will not turn on at all. Also it has some big practical advantages. The ICE can be made smaller, and can be optimized for its task and made to operate at only at its ideal RPM -- the Prius' CVT means it can operate in a narrower band, but it still varies as it has to increase power to the wheels to accelerate.
So I think it's fair to call it an EV. If you're only doing a short commute each day, then that's absolutely true, since the car will drive on nothing but electric power. If you need to go farther, the generator kicks in, extending your range. It's not just marketing, it's correctly emphasizing the real practical advantages that differentiate it from a normal hybrid.
Oh, and in most places, yes it is cheaper to use electricity from the grid instead of gas. Especially if you charge during off-peak hours.
The enemies of Democracy are
The 50 MPG is based on using only the gasoline generator without any energy input from the batteries.
So, if you start up in the morning with completely dead batteries, you can still drive and get 50 MPG.
They should design hybrids so that the transmission switches the energy source. Higher gears switch to battery power, lower gears switch to gasoline.
That's pretty much the opposite of what you want. Electric motors develop peak torque at low RPM, gas engines at high RPM. In fact I wonder about the losses in the additional transmission if you want to drive the wheels from the gas engine; mechanically it makes more sense to use the electric all the time (much simpler transmission) and run the gas engine at a constant speed (more efficient) to keep the batteries charged.
-- Alastair