I have a question, that may of been answered already. I've read that the Toyota Prius I and II can go along minus the gas engine anywhere from 30 to 45 mph on it's Hybrid battery? If this is true, then why can't the Prius I and or II also run on it's battery even after it runs out of gas? Does the inboard computer know if it has gas in the tank? (Some smart car). I find it hard to believe that the Prius or any other future Hybrid cannot travel by itself on the battery as long as you don't exceed the speed limit in order for the gas engine to normally kick in. I myself try to fill up around a half a tank, even when making long trips across country.
I guess the big wheels at Toyota have already considered this option.
One more thing, I still believe that solar engery can be added to the Hybrid, even if its running the turning lights during the daylight hours, that would save the battery and or gas engine.
thanks for your time.

Thanks Bob and welcome as a new member.
I'll let a more Prius specific person fill in the blanks.

However I can say that to electrically propel (or assist) a ~2,700lb vehicle requires a certain ammount of energy to be consumed.
Most of that replacement comes from the gasoline engine. The gasoline engine will consume extra fuel to replace what was lost.

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT

Well, it wouldn't work with the hybrid system honda runs, just not egnough electric motor there.. But it would seem to be very doable in the toyota style system.. I would not expect much range, maybe a mile or 3, to get you to a nearby station..

Really thou, you have a range of what 700+ miles?? any you can't manage to find a gas station?

I have run my Toyota Prius I out of gas. Everything started blinking and beeping, and I just made it to the gas station which was about a mile away. On batteries alone.

According to dr Wolfgang Steiger of Volkswagen, the computers only take a fraction of the energy that can be stored in the NiMH battery of the Prius for propulsion. This is needed to ensure that the battery lasts the lifetime of the car. Next generation Li-Ion batteries can dramatically improve the amount of energy that can be used, he says.

Johan Erlandsson

See mileage data for my 00 Prius.
See my environmental performance (still in swedish only, feel free to ask).

Well, the motor can only give you so much in terms of acceleration. Since you mention filling up half way through the tank, I'd assume you drive a Prius. Then you already know how slow the car accelerates in EV mode right? If you want more, you push the pedal harder and the engine fires up. That will happen even at very low speed. When you run out of gas, the engine is not there, so nothing happens when you push harder. With enough juice in the battery, you *can* drive the Prius in EV mode even right now. Just be gentle on the gas pedal.

<!--QuoteBegin-mastersgtbob@Jul 20th 2004 @ 11:31 PM
[...] One more thing, I still believe that solar engery can be added to the Hybrid, even if its running the turning lights during the daylight hours, that would save the battery and or gas engine.[/quote]
Hmm... I wonder how much that is going to buy you. Canadian Prius has day time running lights that cannot be turned off. It's like 50W each if I remember it correctly. And I don't believe my mileage suffers noticeably because of that. I think you'll need one huge panel to make any real difference.

Andy

Well, this is a stale thread, but I might as well offer an opinion.

When it comes right down to it no car should ever be driven until it runs out of fuel. Most manufacturers will tell you that running out of fuel is a very bad thing. This is especially the case with vehicles with pressurized fuel systems and fuel pumps in the tank. It would be a long and drawn out story to detail why, but that is the case.

If you drive diesel you don't want to ever run out of fuel because if you do then you have to have your fuel lines bleed of air before your vehicle will run properly again.

I think many of the same concerns apply to the Prius, on top of the fact that the car will drive by battery only, if it has to, but it isn't advisable. Especially since if you get too close to the lowest SOC that the vehicle will allow, at that point the car just shuts down and basically will lock out the user until a Toyota diagnostic computer is hooked up to wake the car up again and convince it to start charging the HV battery. That is not a good situation to get into.

So, my advice is to not ever run out of gas.

As for solar panels, I'm not sure the benefit unless you stored you car outside during daylight hours. I'm fortunate, I park mine in a garage at home, and at work and my commute is so short that it wouldn't be outside enough to really be of much help. I could see it for keeping the 12v system fully topped off, but even then again. Sure, when you were out and driving it might help, but I have my doubts that it could provide any significant power to the car. Well, I've been wrong before.

It has been said:
Hybrid drivers come in 3 flavors, greenie, techie and cheapie. Pick any 2.
2005 Prius, Melinium Silver over gray, package 5 (AI)

Sure it can - I have a non-US model (in New Zealand) with the 'EV-mode' switch (I understand these are disconnected in the US) - If I press it and so long as I stay under 44kph (27mph), don't hit any heavy lifting (steep hills) and the battery stays out of the 'purple zone' I can go 3-4 miles on the flat in EV mode .... go for miles and miles down hill ... and almost no distance up hill

Correct. But, this is very hard to do without EV mode. With a steady foot and practice, you can go for a bit on a straightaway or downhill slope less than 42 or so, but in reality the engine likes to kick in.

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I read a post on another forum where someone, as an experiment, allowed himself to run completely out of gas. He reported he was able to drive in pure electric mode for I think 2-3 miles.

Yes, at the risk of ruining the hybrid system. The batteries aren't designed to become completely drained, nor are they designed to be completely charged. It goes without saying, but don't run out of gas

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