ev mode

[mymimi]

what kind of mpg are you getting with evo mode? and how much city driving?

[efusco]

do you mean ECO mode? Or EV mode?

[mymimi]

Originally Posted by efusco

do you mean ECO mode? Or EV mode?

EV mode

[Tideland Prius]

Don't expect an mpg boost with EV Drive Mode. It's meant for short distances only (e.g. moving the car in/out of the garage) or moving about the parking lot.

[mymimi]

Originally Posted by Tideland Prius

Don't expect an mpg boost with EV Drive Mode. It's meant for short distances only (e.g. moving the car in/out of the garage) or moving about the parking lot.

i was thinking it might help short drive, about 2 mile

[ggood]

Originally Posted by mymimi

i was thinking it might help short drive, about 2 mile

Both the manual and a lot of people here say that in the long run, it actually lessens MPG if you use it all the time. 2 miles is about its limit, and then it has to be recharged by the gasoline engine running.

[DaveinOlyWA]

city driving i am probably getting between 40 and about 80 mpg.... not narrowing it down much, but that is how city driving is.

it can really make and break ya as far as mileage goes. now there are two kinds of city driving.

the dense traffic kind (downtown): where average speed is probably 15-20 mph, max speed 25-30 mph. in this it can be as low as 40 mph if you get caught by all the lights, have to make a bunch of left turns, etc (left turns kill mileage because you almost always have to come to a stop to yield to oncoming traffic and frequently have to "get on it" to shoot a gap, etc.)

then there is the urban traffic (suburban) ; where its mostly major arterials...now they are also heavily traveled. speed is 35-45 mph, but they are also multi-lane, lights at much longer intervals and on straight roads where they can be seen from blocks away and timed.

this allows you to be able to moderate your speed in hopes of hitting all the lights green. hypermiling is easier here simply because you are not really holding up traffic since anyone behind you can simply go around. here is where you can get 80+ mpg with nothing more than simply monitoring the surrounding traffic conditions and doing whatever you can to not use your brakes.

now dont get me wrong, i have done the downtown and got great numbers. our downtown has two major one way streets at 25 mph, but there is lights 1-2 blocks apart for nearly two miles. time it right (easy if traffic density is just right) and you can hit 100 mpg going west which is downhill, and 50 mpg going east. (average is 5-10 stops) there is also days when you have much more stops. besides the lights, its downtown so parallel parking is allowed, traffic can be a nightmare, etc to where going west can be as low as 60 mpg (remember, going downhill!!) and east i have actually been as bad as 27 mpg.

so, all in all... the adage YMMV is all i really can say that is valid... well that an EV mode should never be used for more than say 4-6 blocks

[daniel]

Originally Posted by mymimi

i was thinking it might help short drive, about 2 mile

Absolutely not! The reason is that all the energy for the car comes from gasoline, and there are inefficiencies inherent in charging the battery from the gas engine.

EV mode is efficient for extremely short "trips" such as moving the car from garage to driveway or between very nearby (one block or less) parking lots, as you avoid the inefficiency of starting the gas engine.

Also, one of the ways the Prius gains efficiency is by always running the engine near its design output. When the power demand is low, the excess goes to the battery. The inefficiency of charging the battery is offset by the efficiency of running the engine at its best output. This means that sometimes the battery will be near full, and then the engine can shut off and the car can consume some of that energy.

EV is efficient under the following conditions:

1. The battery is relatively full. AND:
2. The power demand is very light (steady speed, no uphill). AND:
3. For reasons unknown, the car is reluctant to slip into electric mode on its own. (Perhaps because it's not yet in Stage 4 operation.)

Here's an example of efficient use of EV mode:

You are driving on residential streets with a stop sign at every corner or every other corner. The battery is relatively full. You allow the gas engine to run as you accelerate to 25 or 30 mph, then you engage EV mode as you drive at steady speed (not uphill!) to the next stop sign. At the stop you take the car out of EV mode, so it uses the gas engine to accelerate back to 25 or 30 mph. Then engage EV mode again. Etc.

Use EV mode for short distances, at very gentle power demand, when the battery is at 6 bars or above. Sometimes in very cold weather the car will not want to shut down the engine because you are running the heater. Then when the battery reaches 6 bars, you might want to use EV mode until it's down to 4 or 5 bars, and then start the engine again.

Do not use EV mode to take the battery down to 2 bars (where the car will start the engine) and then wait for it to charge and take it all the way down again. This will probably not hurt the car, but it will waste fuel.

Moderation is the key. Maximizing time in EV mode is wasteful.

MOST OF THE TIME the car will do best if you allow it to decide when to go electric and when to run the engine.

[ArtH]

+1 to what Daniel said.

I got the EV thing and I thought is would be better then sliced white bread. It isn't magic. It looks like magic when you are using it, but in the end you will be disappointed.

But, there are times (if you play your cards right) that the EV mode can take you "over the hump". I drive I-66 from Manassas (VA) into DC (Washington) sometimes for work. I-66 turns into Constitution Ave when you get to DC. Then there are about 4 or 5 lights that are poorly timed in the next 1/2 mile and everyone races to the next light as if trying out for Nascar jobs.

You approach these lights while travelling 55 mph on a long downhill as speeds are reduced to 35 mph and 25 mph after the first light.

I try to hit the first light with the battery charge a really bright green. I got energy to burn.

The EV mode allows you to accelerate a bit more then when the ICE will normally start without the EV mode. And it allows speeds up to 34 mph before the ICE must start.

I can get through these 5 tough lights and this has improved my trip mileage by a few percent. High five. Maybe an ounce or two of gas was saved.

When I leave from home on a trip, I use the EV mode to move the 250 yards from my garage, a right and then another right, and then I take a left on a main road and I got to get to 50 mph. The ICE starts and I drive about 1/2 mile uphill. I coast 1/2 mile down a hill to a light at an intersection that is always red. Always. When I stop, I put in the EV mode again. I take a left and get to 50 mph going uphill. The ICE starts again. At the top of that hill, I can coast back down and charge the battery a little. I then drive at 50 mph for a mile and then an uphill. The Prius is now warm.

I never got below 5 battery bars, I never really borrowed that much from the battery. It really didn't slow up my warmup that much.

I am sure other will disagree with me, but I think there are times when it can save an ounce of gas or perhaps two.

I visited a college buddy a few weekends ago and we and our families played frisbee and hacky sack all weekend. And ate good. And I showed them the Prius. They liked it and were suprised at the roominess.

When we were leaving (we didn't find time to let them actually drive the Prius all weekend), I kicked it in the EV mode. I backed up and then put it in Drive and stopped and we said goodbye one more time. I kinda rolled out their driveway and down the road in electric mode. They called later and were impressed. Another potential customer for the Prius. In the EV mode, perhaps someone else in the future could decrease their gas usage by 2/3 rd's.

Regular people put their keys in their cars and turn them and the car starts. The engine continues to run until the turn the key the other way and turn the car off. They really can't believe that the engine actually turns off many times in a trip (they heard it but they don't believe it).

When they see a Prius, their eye's open. Perhaps the world can be a better place. Perhaps we can all save gas by buying a hybrid because they actually do work. You can actually drive over 25 miles without needing to plug something in.

While the EV mode "button" won't really save you a million dollars, when used correctly it can save an ounce or two of gas, and perhaps convince another person to consider a hybrid.

I want the $10,000 Hymotion batteries.

Art

[abra]

I have to agree, its not a big mpg saver.

I use mine to get to the main road (2/3mile, mostly down hill) then i use ICE to get to up speed (45mph) I have found that it saves me about 8-10 miles per tank.

On some streets were the speed is 30-35mph and the road is hilled just right, i use it. Ev on up then recharge on the down.
this morning a nailed 99.9 on a 2 mile strech that i usaul can get 85 without it on. Man i love streets.

Also i use it alot when i take out the trash and check the mail. drop/box is about 200yrds up a slight incline.

i wouldnt say im a hypermiller because i love drive it @ 85mph on long trips (mfd reports 38-40mpg) but i do coast on down hill and nail it on up hills. With cruise i get 34 at these speeds.