recommended approach for efficiency on-highway?

[wishboneash]

Great post. Completely agree. I have people honk or act nasty even in non-highway driving situations. Maybe they had a bad day shelling out $70 at the gas pump! I also drive on the far right lane at 55 mph if possible. There are always those who like to overtake on the right most lanes. Unfortunately for them I am not going to speed up just so they can reach home/work 1 minute earlier.

Heavy traffic is an EV's friend!

I've experienced a few rare instances of road rage from drivers who object to my driving at the lower end of the legal speed limit in the slow lane of Los Angeles freeways. It isn't pleasant, but I will absolutely not give ground. I can flip the bird right back with ease.

So I've been casually looking for an affordable, programmable electronic display strip to install in the rear window of the Leaf, something I can pre-program with a few scrolling messages, such as:

"If you don't like the way I'm driving, there are five other lanes to your left. Feel free to use them."

"Your vehicle is too close to mine for safe driving. If I have to brake hard the resulting accident will be your fault."

"Flashing your lights/honking your horn will not make me speed up. Move to another lane and pass."

Etc., etc.

Anyone know where to buy an affordable, portable display strip?

 

[Caracalover]

I find a sign that says: "Saudi Arabia Loves You" stops all of these tailgaters from being angry.

I tend to speed up and slow down so as to not impede the flow of traffic. I always have enough energy to do so. If I have to go slower in my off freeway travels to be able to do this, so be it. There are times when I can coast up to 65 or more MPH, and while I might regen a few kw by going slower, it hardly seems worth it. The benefit is too small to give EV's a slow poke misnomer, and safety is better served by being one with traffic, rather than the one fighting it.

 

[jlsoaz]

I find a sign that says: "Saudi Arabia Loves You" stops all of these tailgaters from being angry.

We've had a few ideas for bumper stickers here. I may have one made up as a variant of the one you mention. Do you actually have that as a sticker on your car and does it actually generally defuse the anger?

I tend to speed up and slow down so as to not impede the flow of traffic. I always have enough energy to do so. If I have to go slower in my off freeway travels to be able to do this, so be it. There are times when I can coast up to 65 or more MPH, and while I might regen a few kw by going slower, it hardly seems worth it. The benefit is too small to give EV's a slow poke misnomer, and safety is better served by being one with traffic, rather than the one fighting it.

You allude to the matter of the slow poke misnomer.... i.e.: how fast or slow we go also has a bit of effect on what people perceive with EVS, and I think this has been a bit on my mind, but I am learning as I go along. So, I may have done a couple of quick 75 mph test rides for others for one exit to bring home the good pickup and speed, but must balance that against some of the advice to go slower. In your particular post I also like your keeping an eye on safety and acknowledging that sometimes it may (in the opinion of some, with which I strongly agree) speeding up at least enough to be more in the flow of traffic.

To report, my overall recent activity after having started this thread is that I haven't really tested out the highway questions yet because mostly I've been making more of a point of driving on side-roads, where possible.

A side-note that I recently ran across the TV show "Border Wars" and the first season (5 episodes) takes place where I live. This doesn't give a good idea of the highway driving, but does add a slight bit of spice to the question of identifying side-roads to the highway. I'm not trying to say they are frought with the dangers that the agents face much further away from the interstate, only it pays to have a slight bit more awareness.

 

[jlsoaz]

I'll keep an eye out for any further info to supplement this, including whether Nissan says or has said anything.

Not going below the VLB warning is wise counsel, however I wouldn't hold my breath waiting for Nissan to give that same "wise counsel".

Hi Tony:

Even if there is some reason to be skeptical or cynical of Nissan helping us on some matters, and even if they show signs of questionable managerial decisions as to what they do with their lawyers' advice, I'm scratching my head as to why they wouldn't give good counsel on battery preservation practices on the low end of SOC, when they are so clear about it on the high end of SOC?

I realize that I have some to learn and catch up on with the Leaf, but it seems that some here seem to report going below 20% or even 10% SOC many times, and some of those don't seem to perceive it as a serious threat (or as serious a threat to the high end SOC concerns) to range degradation. Are they misperceiving the matter?

Unless you believe the car goes 100 miles, the LEAF's bad instruments are the reason why Phoenix LEAFs show up to 4 capacity bars missing, etc.

I haven't spent that much time here and so at first read your comments and took them literally. I went to one or two of your links though and I'm thinking you were being sarcastic. I quite like your link here:

http://www.mynissanleaf.com/viewtopic.php?p=220120#p220120" onclick="window.open(this.href);return false;

If it's done well (and it looks like yours and assumably also some others' is done well), then this sort of sober-minded perma-documentation approach to hot-button-issue discussion can, I think, help readers achieve some good understanding of the matter.

 

[Hartleaf]

A trick that I have mastered is: start at cruise control set at 52. Wait for a lorry to overtake me. Follow lorry at 3 to 4 car lengths. Today I did between 55 and 61 mph and still got 7 miles to each bar. Did my 72 mile commute and used 10 bars. Dropped to 2 bars as I parked up. Well not all the commute was at 60, there are a few slow sections at each end.

Something I do notice in autumn is leaves blow along behind the lorries. Learn from nature, and let a lorry give your leaf a tow.

 

[jlsoaz]

A trick that I have mastered is: start at cruise control set at 52. Wait for a lorry to overtake me. Follow lorry at 3 to 4 car lengths. Today I did between 55 and 61 mph and still got 7 miles to each bar. Did my 72 mile commute and used 10 bars. Dropped to 2 bars as I parked up. Well not all the commute was at 60, there are a few slow sections at each end.

Something I do notice in autumn is leaves blow along behind the lorries. Learn from nature, and let a lorry give your leaf a tow.

Thanks for the trick, very interesting to know.

 

[LEAFer]

I don't know what a "lorry" is ... (just kidding) ... but I do EXACTLY the same thing :lol:

See my trip report (EE 4.8 & 5.2 mi/kWh) here: http://www.mynissanleaf.com/viewtopic.php?f=31&t=9170&start=47" onclick="window.open(this.href);return false;

(Scroll down a little in that thread for the full report.)

 

[mrdcmills]

I travel I75 regularly. I find there's usually a truck with a 60 mph top speed I just tuck in and cruise at about 2-2.5 KWH. Or other days I just rip it at about 80. I have 12 hrs to charge at work.
Dana

 

[mkjayakumar]

As many here have observed, the best way to get a range is to Draft behind a big truck. The closer you are, the less your consumption. It was amazing the other day, that i was able to draft a truck at 2 car lengths and get as much as 5.5 miles/kWh for nearly 15 miles at 65mph. At that rate I can go over 75 miles on the freeway with no sweat. It was almost a revelation. The effect of drafting is something you have to try and see how effective it is.

 

[smkettner]

Two car lengths at 65 mph :shock:

I prefer three seconds or 264' at 60 mph.

 

[jlsoaz]

Two car lengths at 65 mph :shock:

I prefer three seconds or 264' at 60 mph.

Agree. I like the enthusiasm and recommendation for drafting large semis pushing the air out of the way, but following too closely for safety is not good, so I wonder if there is some balance to be struck there, sacrificing some of the energy efficiency gains for the sake of safety and respect for other drivers, but still following closely enough to get some energy-saving-benefit. I don't know if the air further back would be conducive to saving energy or not. It might be necessary then to identify a truck at 55 or 60.

I remember when I used to live in SoCal, the first time I was in traffic near LA at 55 to 65 mph. It was one of the more ridiculous situations I'd been in, I thought then, with cars too close to each other (in my view) for those speeds. I got a little used to it when I used to visit, and I may have been mis-perceiving things, but it continued to bother me.

 

[ztanos]

Mythbusters did this a while back, here is their results.

Edit: Realized this was near impossible to read...

control 32 mpg
100ft 35.5 mpg 11% increase
50ft 38.5 mpg 20% increase
20ft 40.5 mpg 27% increase
10ft 44.5 mpg 39% increase


Edit2: Granted the LEAF should be more aerodynamic than the car they used and will probably yield greater results, but this is a baseline at least.

 

[Herm]

The problem with drafting a truck is that you dont know what is just in front of that truck.. since that lack of information does not bother you then it should not bother you not to see whats behind you.. flip up your rearview mirror and just cruise at 55 on the right lane.. ignore everything back there and get a good audiobook to listen to.

Lets say you are taking a hwy trip of 70 miles, at 55 it will take you 76 minutes and at 65 it will take you 64 minutes, a difference of 12 minutes yet your car will consume 20% less energy.. I guess its like having 14 fuel bars in the Leaf instead of 12.

 

[mkjayakumar]

Today I made a 73 mile trip with 65 of those on highway drafting behind trucks for at least 50 of those miles at 2 car lengths. I reached home with 5 miles in GOM flashing and all bars gone, but not hit VLB yet. Efficiency 4.1 m/kWh. Unfortunately the trucks all go at 70mph or close to it and so I had to maintain that, which is the speed limit here in Hwy 121. There is no way I could have made this trip and got home without drafting, unless of course I had driven 15 miles below the limit at 55mph and cars coming close behind you, getting annoyed and changing lanes and whizzing by.

I think - not a scientific analysis by any means - going 55 is just as efficient (in terms of energy usage) as drafting behind a truck at 2 car lengths going at 70

I understand the risks of tailgating, but a truck tends to maintain a larger distance to the vehicle ahead and is not prone to sudden reduction of speeds, as a smaller vehicle might.

Here at 121 which is a toll road, it is hard to find trucks sometimes.

 

[Nubo]

Two car lengths at 65 mph :shock:

I prefer three seconds or 264' at 60 mph.

Agree. I like the enthusiasm and recommendation for drafting large semis pushing the air out of the way, but following too closely for safety is not good, so I wonder if there is some balance to be struck there, sacrificing some of the energy efficiency gains for the sake of safety and respect for other drivers, but still following closely enough to get some energy-saving-benefit. I don't know if the air further back would be conducive to saving energy or not. It might be necessary then to identify a truck at 55 or 60. ...

Everyone please take a good look at the back end of a semi -- specifically the area your vehicle would be striking in the event of a collision. It's not very forgiving.

If you're LUCKY, there's a steel beam there to prevent your vehicle from diving under the truck and decapitating you. And if you're really lucky, the beam is adequate to the task instead of having been slapped on for bare compliance.

I would strongly recommend not trying to get an aero advantage by riding closely to the back of a semi. Though few people follow it, the general rule for safe following distance is 4 seconds. At 60 mph that's over 350 feet of following distance. And it's a good idea when following something as unforgiving in a crash as a semi truck.

 

[Caracalover]

Just to add to the horror of following a semi too close. My dad would follow trucks in the rain to add traction. One day on his way to work the truck in front of him ran over a steel bar, kicking it up and through his windshield. It caught him just below the eye. He managed to get to the side of the road, and he put a white flag out of the side window which no one responded to. He eventually drove himself to the hospital. This was before cell phones, he was in an old VW beetle.

Mud flaps are supposed to stop this from happening easliy, but it can still happen.

Following any vehicle will aid you. Allowing it to break the wind for you as it passes you while you maintain a slower speed works too, and is safer. If traffic is heavy enough to make you feel uncomfortable at a slower speed, speed up until the traffic gets around you. If you are only a few miles slower than others they will get around you safely, you can draft them safely, and then slow down when traffic clears.

Not watching traffic should NEVER be a policy, as someone here suggested. Always watch the rear, side, and forward traffic, and remember not only your life is in the balance, but a mother's child is also in your hands.

 

[Herm]

Not watching traffic should NEVER be a policy, as someone here suggested. Always watch the rear, side, and forward traffic, and remember not only your life is in the balance, but a mother's child is also in your hands.

Oh by all means watch the traffic coming up behind you.. just ignore that SUV approaching you at a speed differential of 15mph.. dont speed up and if you get annoyed just light up your brake lights for a sec, please do this only on the right lane. Flip up your rearview mirror if you live in fear but obviously you are fearless if you are tailgating a semi.

The truth here that you people cant stand driving at 55mph and blame the drivers behind you or you dont want to "inconvenience" them. Whats the hurry?

Are drivers in CA so distracted that they will run into the back of your car at 15mph?

 

[thankyouOB]

The problem with drafting a truck is that you dont know what is just in front of that truck.. since that lack of information does not bother you then it should not bother you not to see whats behind you.. flip up your rearview mirror and just cruise at 55 on the right lane.. ignore everything back there and get a good audiobook to listen to.

Lets say you are taking a hwy trip of 70 miles, at 55 it will take you 76 minutes and at 65 it will take you 64 minutes, a difference of 12 minutes yet your car will consume 20% less energy.. I guess its like having 14 fuel bars in the Leaf instead of 12.

what herm said, especially on the issue of how much time is saved on trip. it is really small for all the extra energy required.
i am especially leery of not being able to see what is in front of the car in front of me.
i will move over to the next lane if I am behind an SUV for that reason.

 

[jlsoaz]

Not watching traffic should NEVER be a policy, as someone here suggested. Always watch the rear, side, and forward traffic, and remember not only your life is in the balance, but a mother's child is also in your hands.

I am more in your camp I think, though guilty of the occassional transgression. Driving is the most dangerous thing most of us do in our normal daily lives, and it seems like a good idea not only to follow good practices, but also to talk about and if necessary debate them with our fellow drivers.

I once had a manufacturing job where OSHA and the insurance companies came in and (quite correctly) woke up the employer to the need for immediate big improvements in safety on the site, and one of the practices my supervisor followed meticulously after that was to hold regular safety meetings, but also to mention frequently that studies had shown that discussing safety can help lead to safety improvements. I don't know if this was true, but it made sense to me. We were given the floor to get our safety concerns out into the open and there were a few points on which I thought we made some improvement by having everyone present to work them out a bit and get on the right page.

Anyway, I'm telling the story because it seems to me that in some cases we may agree here on safe driving practices, and the prioritization of safety, and in some cases we may not agree, but I for one like to see the discussion brought out a bit.

All that said, I am reluctant to keep back 350 feet (more than one football field) at 60 mph. That seems like a textbook recommendation that very few drivers follow. I've always felt a bit uneasy about this though. I wonder if there is are traffic safety publications where experts take a look at this.

 

[HairyCairy]

I find myself behind the Lorry's all the time. I always follow the rule if I can not see the Mirrors of the truck then I am too close.
I am also a big fan of staying with the flow of traffic. I would love to keep the steady pace of fifty five as it seems to be most efficient and logical, but some when traffic is constantly racing up my rear; going around me then I give it a touch to sixty and sometime a couple more flicks to sixty four based on what traffic is doing.
I just find that when ever I am the on going against the traffic flow I am causing unwanted stress on other drivers which may lead them to make a poor judgment call. I empathize a little bit with ICE speedsters and acknowledge that i don't know the whole story, like they could be having a ruff day and I am the straw that broke the camels back.