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The article on Pulse and Glide says on how to pulse:

"When the car needs to get up to speed, gently accelerate. As much as possible, avoid using energy from the large hybrid battery while accelerating."

That's not very specific. What rates of acceleration are more efficient or less efficient? How do I 'avoid using ... battery'? If the energy diagram shows that I'm drawing on the battery, do I accelerate faster or ease off? Is this only applicable in a certain speed range? How can this be managed when accelerating at speeds below 30mph?

TIA for info and suggestions
 

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I don't fully understand P & G either. I find that it is quite difficult to keep acceleration in the sweet spot between battery and ICE (no arrows). I'm surely not complaining about MPG which is hovering around 49-50 in colder temps and with snow tires inflated at 33/31. I'm good at keeping it in battery mode but no arrows is rare even on level stretches.
 

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The idea behind pulse and glide is that the engine is only being used to drive the vehicle directly, and spinning at optimal RPM, and then shutting off. That being more efficient than say overpowering the vehicle via gas, and charging the battery, and then recaliming that energy to power the vehicle. It also requires driving at a optimal wind resistance speeds.

It's a bit of a myth though. First of all, it's really difficult to do in any realistic driving situation: coasting between 30-40 mph without any braking. The milage gains one is likly to see is pretty minimal compared with just driving in an ordinary efficient manner.

For most realistic driving situations the best way is just to drive efficiently in a normal manner: soft on acceleration and braking, don't race.

On the freeway slower is going to be more efficient just as it is with any car. Of course the Prius going 70 is still going to be a lot more efficent than another car going 70, just as the Prius going 30 is far more efficient than any other car doing 30.
 

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Difficult to master, yes. Being a myth that it is unrealistic, or that it doesn't save, no. A while back, a marathon had been done to achieve the highest mileage possible using pulse/glide method on public roads, though I believe they were roads with light traffic. They did have lights however. If I am not mistaken, 100+ MPG was sustainable throughout a tank using several cars. I believe the speed averaged 35 MPH.
Here's the link to the thread regarding the marathon: http://www.priusonline.com/viewtopic.php?t=5659

Acceleration rate was found to not be a major factor, though it was favored to keep a bit of charge current to the battery, especially when the marathon ran into the nighttime.

Above 42 MPH, you probably will find it impossible to have absolutely no energy flow, as the HV is programmed to keep the ICE spinning above that speed. This is a carryover from the Classic Prius, where MG1 could not exceed 6500 RPM, which could not be avoided above 42 MPH without the planetary gear carrier spinning, which is what is attached to the ICE. The new Prius has an RPM limit of 10K for MG1, but still the ICE is made to spin at 42 MPH. If you coasting to the point where you are jumping from power to regen, then you are close enough to neutral to be practically 0.

As for accelerating, accelerate with minimal use of the HV battery. If you ever looked at the CC try to accelerate, it pretty much does this. Fuel consumption in this case is about 20MPG.
 

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wayneswhirld - I'm assuming you meant 'no arrows at all to and from the battery', since no arrows at all would have to be coasting. It helps to know what the goal is.

I think it's very realistic and reasonable to try P&G techniques in regular driving.

Certainly glides at any speed can be extended using the glide technique. It's also good practice for when the rare opportunity comes along to actually pulse and glide, and the activity of looking for opportunities to glide longer teaches better pre-planning, etc.

It seems a lot trickier to figure out how to apply pulse techniques regularly. I'm not too worried about speeds higher than 40mph, since pretty much all of my driving at those speeds is on freeways. When I get on the freeway, I just set my cruise control to 50-60 (traffic allowing) and leave well enough alone.

What's difficult is quickly finding that 'sweet spot', and knowing under what conditions it's possible or feasible.

DanMan32 - you mention 'accelerate with minimal use of the HV battery'. OK, how? Sometimes it seems the computer just chooses to use that battery for no good reason at all. What conditions cause the battery to kick in? Under what conditions, or a what speeds, is battery use unavoidable, or even more efficient?

You also said 'If you ever looked at the CC try to accelerate'. What is the CC, and what does this sentence mean?

On a side note, it seems very odd to me that the most efficient use of the Hybrid is to *not* use the primary feature (big battery) that sets it apart from the gas guzzlers. If this is the case, why do Hybrids make sense?
 

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P&G

I have been trying to utilize the P&G more with my surface street driving but I find that when first getting going in the morning even though I might be coasting, the 99.9 does not come up. Instead it might be anywhere from 20's to 30's.
I have seen some threads on "warming up" your car which with the Prius is just not the same as with regular vehicles. But it does seem that the car "needs" to warm up to work the way it does later when I can easily see the 99.9 on coasting the same areas.
Any ideas?? It only gets into the 40's at the most here in San Diego (sorry Vermonters and other cold weather folks..)
 

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MG2 can be fed electrical power in one of 3 ways: from MG1 powered by ICE, the HV battery, or both. Optimal acceleration seems to be when MG2 is powered exclusively from MG1.

CC= cruise control. To experiment, get your car rolling at about 25-30 MPH, set your cruise. Then push up on the CC stick and hold. After a brief delay, the CC should start accelerating the car. Note the instant MPG rating and the energy flow. You'll see that very little, if any energy is coming from the battery when you are accelerating with the cruise control.

Now although 20-25MPG acceleration appears to be the most energy efficient, it may not be optimal for your traffic needs or personal tastes.
 
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