Stoaty
Posts: 4490
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 8:28 pm

PaulScott wrote:Stoaty, I'm very impressed with your efficiency and agree with your reasons, etc. Just curious, what's the pressure in your tires?
I have been running them at 40 PSI. Didn't intentionally set them higher, got the car from the dealer, checked the tires a few weeks later and they were at 41, so I basically left them there. Recently found the pressure at 37, put some air in to bring them up to 40.

Did my usual work commute today (47 miles) using the Energy Screen reading for miles/KWh for this trip. While there were a couple of minor variations in traffic, it was basically similar. My past results for the commute when coasting down long hills were 6.1 miles/KWh on the energy screen. Today I used cruise control on the downhill runs for both sides of Sepulveda Pass. Speeds were 45-55 MPH depending on traffic. Got a fair amount of regen and ended up with a record (for me) 6.4 miles/KWh for the trip. That is a 4.9% increase in efficiency, which I didn't think was possible given my already conservative driving style. Took a little extra time, not that much.

From now on I will be using cruise control on longer downhill runs and a slow speed as above so the energy goes back to the battery, rather than fighting wind resistance.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

PaulScott
Posts: 196
Joined: Thu Sep 09, 2010 5:44 pm
Delivery Date: 11 Jan 2012
Location: Santa Monica

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 9:20 pm

One of my customers had two RAVs for 8 years, so they are both experienced EV drivers. However, the wife is about 3 months in to the car and is averaging 3.9. She doesn't think she can do better. Her husband is "Gasoline" in our PSAs (http://bit.ly/pWspW1" onclick="window.open(this.href);return false;). We're shooting a video with me as teacher, and Mea as student. Gasoline (Marv) will comment from the back seat. I'm going to show her how to start over and get over 5/kWh.

Your bits like this one are gold:

"From now on I will be using cruise control on longer downhill runs and a slow speed as above so the energy goes back to the battery, rather than fighting wind resistance."

With your permission, I'd like to use it and maybe others.

We all see how inefficiently others drive. So much of that is simple ignorance of basic physics, so that's low hanging fruit. The rest is showing them how to operate the car for better efficiency. If we can affect a tiny % of these drivers, we can save lots of energy.

We hope to make them funny so they'll have better effect, but we'll see.

Stoaty
Posts: 4490
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 9:31 pm

PaulScott wrote:Your bits like this one are gold:

"From now on I will be using cruise control on longer downhill runs and a slow speed as above so the energy goes back to the battery, rather than fighting wind resistance."

With your permission, I'd like to use it and maybe others.
Feel free to use (or modify) the whole list. I don't know for sure how important each piece is, I just know what I have been doing and the results I have been getting. Now when traffic starts to slow down to 15-25 MPH on the freeway I think to myself "this is really going to improve my energy efficiency". I kind of look forward to these slowdowns, rather than getting irritated or pissed off like I might have in the past.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

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abasile
Posts: 1922
Joined: Thu Sep 02, 2010 10:49 am
Delivery Date: 20 Apr 2011
Location: Arrowbear Lake, CA

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 9:35 pm

Stoaty wrote:Now when traffic starts to slow down to 15-25 MPH on the freeway I think to myself "this is really going to improve my energy efficiency". I kind of look forward to these slowdowns, rather than getting irritated or pissed off like I might have in the past.
:lol: +1. Traffic slowdowns are like range extenders! In like manner, getting "stuck" behind a slow truck doesn't affect me the way it used to...
2011 LEAF at 71K miles, pre-owned 2012 Tesla S 85 at 98K miles
LEAF battery: 9/12 bars and < 49 Ah (-28% vs. new)
Tesla battery: 250+ miles of range (-5% vs. new)

Stoaty
Posts: 4490
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 9:56 pm

abasile wrote::lol: +1. Traffic slowdowns are like range extenders! In like manner, getting "stuck" behind a slow truck doesn't affect me the way it used to...
Yes, when I am "stuck" behind a truck lumbering up a long fairly steep grade, I have a great excuse for going 35-45 MPH (depending on the speed of the truck). In addition, others passing me by in the next lane may feel a bit sorry for my predicament, so I get double rewards. ;) If they only knew what my little Leaf is capable of doing! :o
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

PaulScott
Posts: 196
Joined: Thu Sep 09, 2010 5:44 pm
Delivery Date: 11 Jan 2012
Location: Santa Monica

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Thu Sep 08, 2011 10:06 pm

"Traffic slowdowns are like range extenders! In like manner, getting "stuck" behind a slow truck doesn't affect me the way it used to..."

This is exactly what we've been saying for years. I'm not surprised it's a universal feeling. It's like we all took some "lithium" for our anxiety.

ericsf
Posts: 358
Joined: Tue Sep 07, 2010 4:33 pm
Delivery Date: 05 Mar 2011
Leaf Number: 0428
Location: San Francisco

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Fri Sep 09, 2011 7:51 pm

On the topic of regen's efficiency...

I ran into edatoakrun's post about his trip to Lassen Peak and his observations of the Leaf's in up/downhill conditions. http://www.mynissanleaf.com/viewtopic.php?f=31&t=5022
From this and other long climbs and descents I've made, my rule of thumb is now each 800 ft of ascent consumes about one bar, and each descent of 1,000 ft adds one bar. This is assuming road and traffic conditions permit Regen to do most of the braking, and you have 10 bars or less of charge, so full regen is available.

I would not have thought near 80% recovery of ascent energy (by both "coasting" and regen) likely in real-world use on extreme grades, but that's what I'm seeing, and it seems other recent hill climb threads reflect the same experience.
SL w/ QC (3/5/2011) - 11bars on 1/23/2014 @ 54k miles - 10 on 12/23/2014 @ 73k - 9 on 10/5/2015 @ 85k - 8 on 7/3/2016 @ 96k

Stoaty
Posts: 4490
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Fri Sep 09, 2011 8:21 pm

ericsf wrote:On the topic of regen's efficiency...

I ran into edatoakrun's post about his trip to Lassen Peak and his observations of the Leaf's in up/downhill conditions. http://www.mynissanleaf.com/viewtopic.php?f=31&t=5022
From this and other long climbs and descents I've made, my rule of thumb is now each 800 ft of ascent consumes about one bar, and each descent of 1,000 ft adds one bar. This is assuming road and traffic conditions permit Regen to do most of the braking, and you have 10 bars or less of charge, so full regen is available.

I would not have thought near 80% recovery of ascent energy (by both "coasting" and regen) likely in real-world use on extreme grades, but that's what I'm seeing, and it seems other recent hill climb threads reflect the same experience.
Not what I am seeing. I estimated about 0.25 KWh regen from a 1,000 foot descent over about 5 miles. Didn't get close to an additional bar. My subsequent commute the next day showed about a 5% increase in miles/KWh over 47 miles, which fit quite well with this estimate, since I had another 300 foot loss on the other side of Sepulveda Pass. I need to get a SOC meter to better refine this.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

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DaveEV
Posts: 6246
Joined: Fri Apr 23, 2010 3:51 pm
Location: San Diego

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Fri Sep 09, 2011 11:40 pm

Stoaty wrote:Not what I am seeing. I estimated about 0.25 KWh regen from a 1,000 foot descent over about 5 miles.
You're misunderstanding.

Let's say you normally get 6 mi / kWh on flat ground. And then you have your 1000 ft climb over Sepulveda pass. And it just so happens that it's 6 miles up and miles down the pass, 12 miles total. To make the math easy, let's also assume that we it takes 1 bar = 1 kWh.

So normally, you'd use 2 kWh or 2 bars going 12 miles. But a 1000 ft climb will use 1 kWh / 1 bar. And a 1000 ft descent will "gain" you 0.8 kWh / 0.8 bar. So your net result will be a total usage of 2.2 kWh or 5.45 mi / kWh.

Now let's try to make the calculation a bit more realistic.

At 6 mi / kWh, you probably get about 9 mi / bar.

Assuming 1.75 kWh / bar, your 5 mi climb up the hill will use about 2.6 kWh (0.8 kWh to drive 5 miles, 1.75 kWh to climb 1000 ft). And your 5 mi descent down the hill will get you a positive 0.6 kWh (0.8 kWh to drive 5 miles, -1.4 kWh to descend 1000 ft) for a net usage of 2 kWh or 5 mi / kWh.

Now, these numbers are likely off a bit as at a 55 mph you're should be closer to 4.5 mi / kWh than 6 mi / kWh.

This gets you 1.11 kWh + 1.75 kWh up and 1.11 kWh - 1.4 kWh down which would leave you enough regen energy (0.29 kWh) to drive 1.3 miles before you used it all up. Pretty close to your observed 1.5 miles if you ask me!

So in fact - your observations match up pretty much exactly with expectations!

LEAFfan
Posts: 4828
Joined: Fri Apr 23, 2010 6:08 pm
Delivery Date: 08 Jun 2011
Leaf Number: 1855
Location: Phoenix Area

Re: Stoaty's Guide to Energy Efficient Driving of the Leaf

Sat Sep 10, 2011 1:53 am

davewill wrote:
LEAFfan wrote:So you are saying that you use the same power from the energy screen with one bubble as I do with the neutral bubble? Interesting, but not with my LEAF. I can see a slight difference between the two, no matter what speed I'm going in the neutral bubble.
No. I'm saying that the CC always goes back to using the same number of bubbles shortly after I try your "trick" of clicking the CC down 1 mph.
That's strange. Mine always goes into the 'neutral' bubble UNLESS there's a slight upgrade. It's relatively flat here, and it probably isn't there. Looking at the street, you can't really see the upgrade so when it leaves the neutral bubble, then I know.
2013 LEAF SV Del. 2/28/13
2013 LEAF World Record for Most Miles Driven On One Charge-188 miles/8.8 m/kW h
4.8 kW DC PV ($ .91/W fully installed)/ Dec., 2010

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