Cars in Consumption Screen

1 car = 50Whr regenerated

That is how much energy you capture when you use your brakes.

 

And the energy goes to charging your battery, as seen on the Energy Screen.

 

50 Watt-hour is the power needed to light a 50W light for one hour, just to give you some perspective.

Tom

 

Is there any relation between power needed to light a 50W bulb for one hour and the 'battery bars' on the Energy Screen?

To be more direct, do the cars provide actionable information I can use when driving? The mpg data gives feedback I can use to adjust driving habits, but the cars???

 

<div class='quotetop'>QUOTE(j24816 @ Apr 24 2006, 06:46 PM) [snapback]244629[/snapback]</div>

Actually I've heard that it's better to have a long line and few (or no) cars. The Prius is at its best when moving forward, not stopping.

 

I would not worry about it. It is just info that is nice to know. The more you brake will increase the number of regen cars you get but it comes at a price. Nothing is free, you will lose some of the energy transferred from the brakes to the battery. You will get the highest MPG when you avoid using your brakes (ie. coasting). It is just nice to know you are not totally wasting the energy required to stop the vehicle as heat.

 

<_< If you're curious... Page 151 of the 2004 Owner's Manual - "Fuel Consumption" Screen "Item 2" describes the symbols to which you refer. (Likely same page or close) in succeeding Owner's Manuals.

 

<div class='quotetop'>QUOTE(j24816 @ Apr 24 2006, 06:46 PM) [snapback]244629[/snapback]</div>

From numbers I scrounged up (ironically toyota didn't have these easily available), the batteries can hold about 1.3kWh, or 1300 Wh (26 light bulbs). Under "ideal" conditions you get a power mileage of about 4 miles per kWh. How that converts to the bar screen, I think there are 8 bars, 1300/8 = so each bar is rough 162 Wh worth of electricity. It should be mentioned though that that, much like the bars for your gas remaining, might not be equally distributed, also you only get the green symbol car if you regenerate that energy, if your gas engine charges up the battery you don't see that green car symbol.

No, the cars tell you over 5 minute time periods how much regeneration you got back so you can get an idea of your driving habits. I personally dont find that screen terribly useful for teaching how I'm driving, sure it lets me know how I drove the past 5,10,15, etc minutes but I dont remember what exactly I did. The drive train system screen (one with arrows) is much more useful in teaching you how to drive, since that gives you real time data to what your instantous MPG is, and whether or not you are using gas or electricity or recharging.
Having more cars (more regenerated power) doesn't necessarily equate to "better driving" though, if you live on a hill and drive down it, most likely you'll have more green cars the first 5 minutes of your trip than the last 5 minutes when you're coming home, you shouldn't see that you doing a good job driving, it just means you're using the fact that you live on a hill to assist you down it slower (ie you're using regeneration)

 

While the green cars on the consumption screen may not be all that useful, wouldn't their absence after a likely regeneration event (lots of braking, or long downhill) be indicative of possible problem with the regen system?

 

Lack of little video-game regen cars means you made better use of
your *momentum*, which is also a form of energy storage if you will,
without having to turn it back into battery energy [with the
attendant losses]. Straight-n-steady on a highway for half an hour
with no need to slow down, and you won't see any. Good use of
"gliding", and you won't see many, until you have to stop for that
damned light that just went yellow as you crested the hill right
before it.
.
For perspective, a human in fairly good shape can produce about 250
watts steady-state by working rather hard on an elliptical or similar
machine at the gym. If you kept it up for an hour, that's 250 Wh.
So a green car is a fifth of that, i.e. if you put the car in neutral
and have someone else steer it around the parking deck while you
push on it vigorously for 12 minutes, that's your 50 watt-hours.
.
Four little cars gets you about one "free" mile on motor power.
Hopefully it can be seen from this that the amount of energy needed
to make a car do most of what it does is really quite a lot. We
don't think anything of it when mashing that accelerator, do we?
.
_H*

 

<div class='quotetop'>QUOTE(hobbit @ Apr 25 2006, 07:03 PM) [snapback]245141[/snapback]</div>

It always makes me think of "Soylent Green" where Edward G. Robinson had to pedal a bike to light up a bulb. I've always wanted to do that with a TV, so you had to generate in order to watch.

But that 250 Wh number is pretty generous. That may be possible by elite athletes. The rest of us are at about 150 - 200 Wh, which means you have to ride that bike for five or six hours to generate 10 cents worth of electricity, although in California that electricity might be worth much more.

 

Really good discussion, I learned a lot. Finally understand why 'glide' is considered nirvana, and why getting the cars is not necessarily good. My read is that unless you are on an extended downhill, they indicate poor driving technique (which may well be unavoidable).

After seeing it, the relationship between the cars and the battery bars is obvious.....kind of ticked I did not pick up on it myself!