Imiev efficiency on the highway

[FrostyCanada]

Hello sandange, that's what I'm seeing here in town.

Our speedos (not swimsuits ) seem to run 2-3 km faster.

It explain why people get frustrated when following me on autoroute 13 .... I'm doing 100km/h, but it's actually more like 97km/h.

Brian's

 

[DriveGreen]

One other interesting thing is the imiev speedo seems to be about 2.5 kmph slow compared to the gps.

Are you saying that it would read 80 on the speedometer, and 82.5 on the GPS? Or the other way around?

I noticed that the speedometer in several cars shows a slightly different speed than my GPS. Interesting to oserve but really there is nothing to worry about. The difference is well within the "tolerance" of the cop's radar.

 

[PV1]

What cops? :lol:

I've only seem one person pulled over in the last two months, and that was a Jeep doing better than 10 over the limit until she started tailgating me. We had just passed a local cop sitting on a side road about a half mile before the Jeep caught up to me.

I did some highway testing a while back when trying to figure out a range extender. An 8.5 kW generator would keep the i-MiEV going perpetually at 45 MPH, and I think it was 4 hours at 60 MPH.

 

[siai47]

A little of topic but the last reply mentioned a 8.5 KW generator would be capable of running the I-MiEV at 45 mph continuously. The problem with the "range extender" issue is how much power you really need to complete the task. On one hand the required source of extra power adds weight (and if external like a trailer) drag to the vehicle which increases the output requirement of the power source which adds more weight/drag. On the other hand, unless you really have a long journey, most people overestimate the size requirement of the additional power source. If you start out on the premise that you will have a full battery on departure and an empty battery on arrival at your destination, you can add the miles available from the pack to your range extender power requirement calculation. You only need to supply the battery with enough extra power to slow it's discharge rate so that it is depleted at your destination. Say you use a 3 KW generator to provide additional power. If you wanted to go through the trouble, it would fit in the back of the I-MiEV which only causes a weight increase and no additional drag. Because it is constantly putting 3 KW into the pack regardless of the load the vehicle is drawing, I think you would be surprised at how much range could be added. If there was no place to plug in at your destination, the generator could be allowed to run the entire time starting to add storage to the pack for your return trip.

Kind of a mind thing and a range anxiety reliever but not really practical. You would have to plumb the generator so it wouldn't kill you from carbon monoxide poisoning, listen to the noise, and burn fossil fuels. Then there is the cost of the generator itself. Much cheaper to use the EV for its intended purpose and rent an ICE vehicle for the times you need a long trip. Just to put it on my bucket list, I needed to take the Tesla from Florida to Michigan. Instead of shipping it, which would be the rational thing to do, I started out on a non-stop trip for 1400 miles. The trip that takes about 20 hours in a ICE vehicle took 28 hours in the Tesla which included nine supercharger stops. Fortunately, the stops allowed for some nap time which made the trip possible. It is doable but like a I-MiEV with a range extender, just not practical. And (just to get me sort of back to the thread title and not totally off topic) IMO, the I-MiEV's efficiency at highway speeds due to aerodynamic drag and it's high speed handling characteristics make it unsuitable for cross-country driving even if it had unlimited range. Based on its purchase cost and operational cost per mile, the I-MiEV is still the greatest and most practical vehicle in the world if you operate it within the limits of its intended purpose.

 

[Don]

Kind of a mind thing and a range anxiety reliever but not really practical . . . . Much cheaper to use the EV for its intended purpose and rent an ICE vehicle for the times you need a long trip.

IMO, the I-MiEV's efficiency at highway speeds due to aerodynamic drag and it's high speed handling characteristics make it unsuitable for cross-country driving even if it had unlimited range. Based on its purchase cost and operational cost per mile, the I-MiEV is still the greatest and most practical vehicle in the world if you operate it within the limits of its intended purpose.

I agree 1000%! Buy the car which suits your needs, take advantage of all it's attributes (low cost, light weight, nimble handling, easy parking, easy to get into and out of, great visibility, etc, etc) and live with it's shortcomings - Poor heater, limited range, twitchy high speed handling

If you need a 100 mile range EV, buy one - There are several out there. Same thing if you need 200 miles, though the selection is more limited. If 95% of your needs are easily met with a 60 mile range vehicle, adding the weight and complexity to extend it's range to say 100 miles is something you'll have to live with everyday . . . . like driving an $80K Tesla 25 miles to and from work 250 times a year - Besides being a terrible waste of money and worrying about some idiot denting your $80K car in the employee parking lot, you're also losing all sorts of efficiency using a 4,000+ pound car to do the job much better suited to a 2500 pound econo-box which only cost you $15K

Don

 

[kiev]

i want to agree also, but only 100%...the i-miev is absolutely the most fun and the best-kept secret out there. Now it's like a game--how far can i stretch it before the turtle rolls over and dies. Am i going to make it or have to call for a flat-bed?

 

[barrylevine]

New owner here, love my metallic blue 2016 iMiev - so much fun to drive. I drive 3-4 times per week to musical gigs scattered over metro-west Boston, much of it during heavy traffic hours. I used to take the highways in our Toyota Yaris, but have switched almost entirely to non-highway routes in the iMiev. The RR range runs about 85 mi or so, on these routes that average 35-40 mpg speed limits. But the surprising thing is that most of the "back routes" take almost the same time, being about 25-30% shorter. Not to mention far less traffic, and pleasant wooded or small-town scenery.
When I drove back from the dealer on highways, it looked like the battery consumption was closer to the official EPA range of 64 miles - doing 60-65.

I'm not using the AC (range anxiety, I know) and I'm not sure how things will go in the Massachusetts winter.

 

[PV1]

Glad you're enjoying your i-MiEV. How far do you normally drive on a given day?

Several times when driving into Pittsburgh, I'd take the main roads and end up getting there much faster than by taking the highway/parkway. I once bypassed 1.5 hours of sitting in traffic by taking a back road and was at my destination in 15 minutes :mrgreen:. I rarely take the highway, but there are still times when the highway is faster and the range allows (my comfortable highway range is 50 miles, but that's because I'm usually pushing my own air at 60-65 MPH while trying to avoid getting run off by everyone else doing 85 MPH).

 

[Don]

I used to take the highways in our Toyota Yaris, but have switched almost entirely to non-highway routes in the iMiev. The RR range runs about 85 mi or so, on these routes that average 35-40 mpg speed limits. But the surprising thing is that most of the "back routes" take almost the same time, being about 25-30% shorter. Not to mention far less traffic, and pleasant wooded or small-town scenery.

We discovered this shortly after buying our first iMiEV in 2012 - Now we always look for a back route . . . . even if it's a bit longer, we use less juice getting there than on the freeways

I'm not using the AC (range anxiety, I know) and I'm not sure how things will go in the Massachusetts winter.

Once you get used to the car and what your actual range is, you'll be back to using the A/C without fear - It doesn't affect the overall range that much. Now using the heater in the winter is another matter entirely as it can cut your range by nearly half, depending on what you're asking of the heater. If I lived where it gets cold, I'd have installed a diesel heater years ago, but down here using the heater to keep the windshield clear doesn't affect the range all that much either

Don

 

[blackheart]

I confess that I have not read every post in this thread - and so I may be re-covering some ground here. But at the last charge stop on my first long adventure this weekend (500+ miles in two days), I was at an Aerovironment charger with a leaf owner. He had a mocked up/home-made whale tail made from plexi-glass, pizza tins over his aluminum wheels and pretty much every opening on the front of his car plugged with Styrofoam. He claimed that he was averaging 53% better than stock range with his modifications. He uses this car for Uber and has racked up over 50k in the last two years and has lost about 14% of his battery.

Anyone test out some body mods with the miev to see if we can help our little cars slipstream at highway speeds?

 

[PV1]

http://myimiev.com/forum/viewtopic.php?f=14&t=1745

I think NeilBlanchard has done the most on the aero mod topic.

 

[barrylevine]

Glad you're enjoying your i-MiEV. How far do you normally drive on a given day?

Several times when driving into Pittsburgh, I'd take the main roads and end up getting there much faster than by taking the highway/parkway. I once bypassed 1.5 hours of sitting in traffic by taking a back road and was at my destination in 15 minutes :mrgreen:. I rarely take the highway, but there are still times when the highway is faster and the range allows (my comfortable highway range is 50 miles, but that's because I'm usually pushing my own air at 60-65 MPH while trying to avoid getting run off by everyone else doing 85 MPH).

Gigs are 25 - 100 mi round trips. The better range at lower speeds means that 9/10 venues can be driven to in the iMiev. I'm figuring in winter that the heated seat and a lap blanket may do the trick, although defrost power consumption may be another matter. 12v heated motorcyclist gloves?

I have to say that my whole experience of driving has changed. I used to hate having to brake for a light or due to some traffic. Now, I'm just recycling a bit of kinetic energy. Hills are cool (downhill with needle into the blue charging zone). Even sitting in traffic - don't love it, but I'm not sitting there emitting fumes. And the car is relatively quiet.