Pushing the Range Limits; Running on Empty

I had to pick up my son this evening from baseball, and take him to a Boy Scout function. I took my wife to "edge-e-kate" her on how to maximize the range of the car if you get stuck somewhere.

We started out with 19 miles remaining (and 3 bars). My rule of thumb is each bar is 6 to 7 miles. If we just drove "normal", we could count on 18 miles (3 bars multiplied by 6) and stretch to 21 miles with some conservation measures.

I sent the "flight plan" to the LEAF with Google maps, and loaded up the route into the LEAF's magic box. It said 16 miles roundtrip.

Conventional wisdom would mean that I'd make the trip, and have 3 miles remaining. I told my wife we'd have 7. So, away we went, coasting down the hills to about 45-50 mph, and keeping a fixed 1 to 2 "power dots" on the uphills, allowing the LEAF to slow to about 25-ish at the top. On level terrain, I hit the cruise control on 38 mph.

Of course, the air conditioning was off. But, I did have to run headlights, making sure not to run the incandescent high beams (the low beams are LED).

We completed the 16 miles round trip, and the "gas" gauge showed 7 miles remaining right until our driveway, when it slipped to 6. Hopefully, my point was made. But, the real test was next.

I had to pick my son up after his Boy Scout event, and had 35 minutes to charge on L2. I quizzed my 8 year old daughter; how many miles can we add if the charger will add 1 mile every 5 minutes. She did get the 7 miles answer.

So, my daughter and I (my wife was tired of this "scary" driving on empty) went to the 16 miles round trip with exactly 13 miles showing; the 6 miles that I arrived with, plus the 7 we added at home in 35 minutes.

I fully expected to have to walk a mile or two, but I did think that there was a chance. So, it was great to watch the miles to-go on the navigation getting closer and closer to the miles remaining in the "gas" tank. The same strategies, pick up speed above the ideal 38 mph downhill, slow up hill, straight and level at 38 mph, never letting the power dots go above 2. ECO mode used for maximum regenerative electricity. Air conditioning / heating off (hey, this is San Diego).

We pulled into the garage with 4 miles remaining.

Well done , I have come to realize that those last two bars have a lot of range in them and I don't need to be scared to tap into them (12 miles is a long ways). Thanks for taking the time to document this and share the results!

-Matt

I only charge to 80% for long(er) battery life, so those last two bars are a significant percentage of my total range.

If I "had" to make it home, I'd take another car, since you never know if there'll be a detour, serious traffic jam, etc. But, I don't want to find excuses why not to use the car that doesn't pollute, and costs the least per mile to operate.

It sure would be handy to have more range, or L3 DC quick chargers.

Great experience! Thanks for posting this.

I will be doing the same for the wife (and myself) when we get ours. Except the only difference would be that our wide suburbia streets would not allow us to go 38mph without lots of SUVs honking at us...45mph seems to be min around here if we want to go any where farther than our own street. But great driving strategy to learn to drive without thinking.

I think I'm going to buy a small Honda or Yamaha generator to carry for the really close ones like this. I probably won't carry it in the car, but instead leave it at home for the inevitable walk home.

Then I can carry the generator to the disabled car, and charge it up enough to get home. Plus, I can use the generator for camping trips.

The last 4 bars seem to get used up much faster at 60 mph on the freeway.

You know that Jackson Browne starts playing every time you say something like that

I don't quite understand how traffic uses more battery. You hardly use any when standing still, and going slow shouldn't use much. Maybe the stop-and-go does it.

garygid said:

The last 4 bars seem to get used up much faster at 60 mph on the freeway.

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Absolutely. My wife's first trip with me in the car was to downtown San Diego, from our house about 18 miles away. Easy trip straight down the freeway, and a trip she makes daily. So, she's always in a hurry, and wants to go "faster". Naturally, I speed up to 70-80mph range, to show her how fast it goes.

The only thing she saw was how fast the mileage meter was dropping !!!

Speed kills (range) !!!!

TonyWilliams said:

I think I'm going to buy a small Honda or Yamaha generator to carry for the really close ones like this. I probably won't carry it in the car, but instead leave it at home for the inevitable walk home.

Then I can carry the generator to the disabled car, and charge it up enough to get home. Plus, I can use the generator for camping trips.

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Do your homework first, Tony. I believe the expert engineers etc., here have said that a generator would have to put out VERY clean power (most apparently don't) or else you risk damaging the charger in your car.

I don't believe anyone has tried plugging their Leaf into a charger yet.....

Jimmydreams said:

TonyWilliams said:

I think I'm going to buy a small Honda or Yamaha generator to carry for the really close ones like this. I probably won't carry it in the car, but instead leave it at home for the inevitable walk home.

Then I can carry the generator to the disabled car, and charge it up enough to get home. Plus, I can use the generator for camping trips.

Click to expand...

Do your homework first, Tony. I believe the expert engineers etc., here have said that a generator would have to put out VERY clean power (most apparently don't) or else you risk damaging the charger in your car.

I don't believe anyone has tried plugging their Leaf into a charger yet.....

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Interesting. I guess it could be run through a filter of some type to clean it up. I didn't know a charger could be so finicky!!! I guess I'll have to do a search to see why they think that.

From the Honda website: http://www.hondapowerequipment.com/products/Generators/

"Honda’s inverter technology allows the most sensitive electronics such as computers and power-sensitive testing equipment – which shut down easily between the initial power loss and the generator kick-in – to operate without interruptions from remote locations."

EDIT: When we did the test drive last October-ish in San Diego, Nissan was charging the cars with Yamaha generators. They had a whole bunch of 'em. I think this one would run the Blink charger:

6500 Watts (54.1/27.1 A) 120/240V of Honda inverter power

TonyWilliams, just curious, did the "low charge" or "very low charge" alerts ever come on for you?

That comes on around 8 miles, I think.

Then, the miles remaining goes to dashed lines after 4 miles (3 and below). Here's my first day with the car:

Nice! I am still running the old Leaf firmware so if I was showing no bars I would most likely be completely out of charge and into turtle mode.

Jimmydreams said:

TonyWilliams said:

I think I'm going to buy a small Honda or Yamaha generator to carry for the really close ones like this. I probably won't carry it in the car, but instead leave it at home for the inevitable walk home.

Then I can carry the generator to the disabled car, and charge it up enough to get home. Plus, I can use the generator for camping trips.

Click to expand...

Do your homework first, Tony. I believe the expert engineers etc., here have said that a generator would have to put out VERY clean power (most apparently don't) or else you risk damaging the charger in your car.

I don't believe anyone has tried plugging their Leaf into a charger yet.....

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It's been a while since this post and I was wondering if anyone has tried plugging their Leaf into a charger yet.

I'm planning on taking our Leaf up to our cabin in the mountains for the summer and while I've done all the calcs and figure that we should be able to make it, I would like to take a bit of insurance along just in case. The "insurance" I'm referring to is a Generac iX 2000 Watt series portable generator ( http://www.generac.com/Portables/iX/Products/iX2000/ ) that I would use in an emergency to power the version 2 EVSE Upgraded Nissan L1 EVSE.

I've read through the board and see numerous cautions about what generator to use. Like some of the Honda generators, this one is rated as being "safe for powering sensitive electronic equipment".

I've plugged the EVSE into the running generator and while it does power the EVSE up the green "Ready" light flashes, which according to the manual mean that there is a problem with "ground". I'm assuming that this is the GFI circuit not able to see any connection between neutral and ground. Is this correct? Would it be safe to try plugging the EVSE into the car to charge it even with the flashing ready light?

So my real question to the community is: would it harm the car if I used this generator to charge the car in an emergency?

Thanks!
Dave

I'm no expert, but I think the answer to this one is simple. If the Ready light is flashing it can't possibly harm the car, because the car won't get any power. In other words, your setup won't work until or unless you can fix the ground problem somehow.

Ray

Although perhaps not ideal from an electrical code safety standpoint, see this post for the solution: http://www.mynissanleaf.com/viewtopic.php?p=71122#p71122

You have to make a special jumper plug that bonds ground to neutral to trick the EVSE into thinking it has a ground. The other solution would be make an adapter that connects the ground pin to a grounding spike you could shove into the actual ground (i.e. the Earth).

Sounds like you are having fun with your family, and probably scaring your wife to death

Any generator is fine, the charger is a transformerless type and should tolerate almost anything. Try not to load the generator more than 80% of its max continuous load (ignore the peak ratings).

GeekEV said:

You have to make a special jumper plug that bonds ground to neutral to trick the EVSE into thinking it has a ground. The other solution would be make an adapter that connects the ground pin to a grounding spike you could shove into the actual ground (i.e. the Earth).

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This grounding spike idea will not work, for two reasons: Number one, if your generator is ungrounded, then it has no connection to earth, so even if you connect the ground pin to earth, you won't have a complete circuit. Number two, at 120V, the earth can never be relied on to carry a significant current, the resistance is just too high. So if the only ground path available to the EVSE is through earth, it will fail the EVSE's ground path detection (assuming it is checking for a low resistance connection as it should).

So if using the EVSE on an ungrounded stand-alone generator, the proper thing to do is bond the ground and neutral at the generator.

Cheers, Wayne

GeekEV said:

Although perhaps not ideal from an electrical code safety standpoint, see this post for the solution: http://www.mynissanleaf.com/viewtopic.php?p=71122#p71122

You have to make a special jumper plug that bonds ground to neutral to trick the EVSE into thinking it has a ground. The other solution would be make an adapter that connects the ground pin to a grounding spike you could shove into the actual ground (i.e. the Earth).

Click to expand...

This is exactly what I was looking for! I spent an hour last night trying to find something like Phil's post but couldn't find it.

My thanks to all who replied! Now I just have to get home, make a new adapter plug for the generator and try it out!

Dave