Stoaty's Guide to Energy Efficient Driving of the Leaf

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
PaulScott said:
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.
 
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.
 
PaulScott said:
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.
 
Stoaty said:
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...
 
abasile said:
: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! :eek:
 
"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.
 
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.
 
ericsf said:
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.
 
Stoaty said:
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!
 
davewill said:
LEAFfan said:
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.
 
LEAFfan said:
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.

At low speeds one can get away with one bubble in CC. Try getting just one bubble at 60mph.
I find the energy info screen more informative than the bubbles anyway, this reveals that there is no such thing as a 'neutral bubble', it really is a low power bubble.
 
drees said:
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!
I see you are just looking at it from a different viewpoint. Glad our observations match.
 
drees said:
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.


Should be a bit higher then this. I get 1.26KWh/1000ft just in the potential energy (not counting losses). I've been trying to come to terms with why it takes me 1.3kW more energy to come home from work than to get there (250ft total drop). Only been logging this for a couple of weeks but it is pretty consistent. Should be half this by my calc. Surely there isn't 50% in losses battery to road.
 
TickTock said:
drees said:
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.
Should be a bit higher then this. I get 1.26KWh/1000ft just in the potential energy (not counting losses). I've been trying to come to terms with why it takes me 1.3kW more energy to come home from work than to get there (250ft total drop). Only been logging this for a couple of weeks but it is pretty consistent. Should be half this by my calc. Surely there isn't 50% in losses battery to road.
Those were just my hypothetical numbers used to show logic behind the calculations. Later I used more realistic numbers.

Back to your situation - perhaps there's a wind difference involved as well?
 
drees said:
TickTock said:
drees said:
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.
Should be a bit higher then this. I get 1.26KWh/1000ft just in the potential energy (not counting losses). I've been trying to come to terms with why it takes me 1.3kW more energy to come home from work than to get there (250ft total drop). Only been logging this for a couple of weeks but it is pretty consistent. Should be half this by my calc. Surely there isn't 50% in losses battery to road.
Those were just my hypothetical numbers used to show logic behind the calculations. Later I used more realistic numbers.

Back to your situation - perhaps there's a wind difference involved as well?

I see now - read too fast. Actually, I think the AC use should explain the ~600W delta from ideal. It is definitely a lot hotter when I'm coming home than in the morning. I'll keep loggin and see if it holds up as we transition into winter. Use of heat in the morning may flip things the other way. Maybe this'll motivate me to build my own canbus reader so I can accumulate and log just the traction kwh consumption.
 
LEAFfan said:
... 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.
Flat! What's that? Yep, there's nothing flat about San Diego, no matter which direction you drive.
 
Today is the first time I used the defogging of the windshield. It works pretty fast, but climate control went up to about 1.5 kW. (D mode)

Just wondering if it is worth the effort of doing defogging as much as possible during regen? This way the energy does not have to go to battery and then to climate control :idea: .

Hey, maybe one can gain a few extra hundred yards by doing this.
 
camasleaf said:
Today is the first time I used the defogging of the windshield. It works pretty fast, but climate control went up to about 1.5 kW. (D mode)

Just wondering if it is worth the effort of doing defogging as much as possible during regen? This way the energy does not have to go to battery and then to climate control :idea: .

Hey, maybe one can gain a few extra hundred yards by doing this.

From a safety standpoint I'd say you always want to keep the windshield clear *before* you need to slow down or brake. The infinitesimal increase in range is not worth the increased risk of hitting the car in front or a small child or deer wandering into the street.

Just saying.
 
I just roll down the windows but tour increases drag as well do either watt its a trade off.
The key thing to remember is that this only is a concern when you are using a highly efficient vehicle
 
Coming late to the thread, but I pretty much agree with your approach. One exception (or maybe it should be broken down into two):
- I drive the speed limit on highways, whatever it is, up to 65 mph. If other drivers want to get pissed off at me because I obey the law that's their problem, not mine. (Observation - nothing pisses off a pissed-off driver like receiving a smile and a wave or thumbs-up in return for their bird. I love it!)
- When the highway is 3 or 4 lanes, which is generally in heavy traffic areas in and around cities with frequent on-off ramps, I drive in the 2nd lane to avoid the on-off merging that goes on in the right lane.
Stoaty said:
For those like me who want to conserve as much energy as possible I offer my recipe--tested over 2,000 miles--for getting the highest Mile per KWh from the Leaf. ...

Not me - I'm money obsessed. Complementary obsessions in this case, though.
Stoaty said:
Any other eco-obsessive drivers out there? :cool:
 
Back
Top