Lake Arrowhead

[sanders1]

I live in La Crescenta, Ca and I recently bought a cabin in Lake Arrowhead. (Exactly 80 miles door to door.) So far I have only driven my other car up there. I'd like to install a 220 charger up there but not if getting up there is going to be difficult or impossible. I don't mind stopping to charge somewhere but probably could only stand 2 hours and only if there was a place to sit and work (Starbucks or whatever.) I'd be heading down the 210 to the 18. Wondering if anyone has made a similar journey and has any tips on how you did and where to charge. Thanks!

 

[miimura]

It should be an easy drive. You might use an additional 25 miles due to the increase in elevation, but on an extended charge, 105 miles should be pretty easy at the speed limit. No need to charge en-route.

 

[Michael Bornstein]

No need to charge en-route.

In principle, I agree with miimura , in practice it is better to be safe than sorry .
I have driven to Arrowhead in my Volt, and it is a long very steep hill. For the first try, I would start with a full extended charge as close to the base of the hill as you can get it. See how it goes. How many bars do you have left when you reach the top? (please report back to us ) Make sure you reserve two bars as a safety net. Then you will know what you have to do the next time. As for the way back down, don't bother to get a full charge before you start. You will gain quite a bit of charge on the downhill run. :lol:

 

[TonyWilliams]

One kilowatt hour = 2,655,224 pound feet of energy.

Driving your 4000 pound Electric vehicle up a 1000 foot elevation requires 4000 * 1000 = 4,000,000 foot pounds of energy divided by 2,655,224 equals 1.5kWh of energy to lift the car.

For a 5000 pound RAV4 EV (with four occupants plus bags) equals 5 million foot pounds to go up 1000 feet.

5 million divided by 2,655,224 equals 1.883kWh of energy to lift the car per 1000 feet.

The 6000 foot climb, therefore, requires 9-11kWh, depending on weight. I'll average 10kWh. That leaves 41.8kWh from a full charge - 10kWh = about 30kWh remaining.

3.4 miles per kWh consumption rate is possible at 65mph, therefore:

3.4 * 30 = 102 miles range up a 6000 foot pass at 65mph STEADY SPEED (the speed doesn't vary, with cruise control ON).

All data above is for a new condition battery at 70F degrees or above, NO CABIN HEATER.

 

[dstjohn99]

For the first try, I would start with a full extended charge as close to the base of the hill as you can get it. See how it goes. How many bars do you have left when you reach the top?

Be careful with this comparison. There are a lot of miles used before the first bar disappears when charged to full capacity (extended), since the additional energy past a normal charge does not show up on the bar graph display.

 

[Michael Bornstein]

3.4 miles per kWh consumption rate is possible at 65mph, therefore:

3.4 * 30 = 102 miles range up a 6000 foot pass at 65mph STEADY SPEED (the speed doesn't vary, with cruise control ON).

All data above is for a new condition battery at 70F degrees or above, NO CABIN HEATER.

I should know better than to argue with you Tony :twisted:

BUT: if you tried the climb at a CONSTANT 65mph, they would find you at the bottom of the cliff. The road is good, but I remember a number of switchbacks where you would have to decelerate to make the turn and then accelerate again until the next turn.

The good news is that if you turn around, it is all down hill which will give you enough power to find another recharge station

 

[sanders1]

Wow. Thanks for all the quick replies! I'm not going to pretend that I understood the equation. Does that mean you're estimating that the climb up the mountain would use up only about a quarter of the battery? If so, this sounds like it could be pretty doable since the drive to the base of the mountain is fairly flat highway driving. Especially since I'd only be making this trip on my own with very little luggage and I think my place is at about 5000 ft. But, yes, Michael is right, I could never drive all the way up at a constant speed - it becomes mostly tight twists and a lot of hairpin turns the higher you go - not sure how much that would bone my range. I think I'll try stopping for a two hour charge and see how I do. BTW, that point about charging my way back down the hill if a go turtle is a good one. Thanks again!

 

[TonyWilliams]

No, I'm saying that the car can go 102 miles up the hill at 65mph. You wanted to go 80 miles, so you would make it in the prescribed conditions.

If you drive slower, say 55mph, it would go even farther. The worst thing you could do is slow and accelerate over and over.

Other issues to shorten range:

1) Cabin heater on (use seat heaters as much as possible)
2) Cold ambient air (air is more dense, and the battery heater will operate automatically)
3) Accelerating and slowing (try to keep as close to a constant speed as possible)
4) Degraded battery (over time, your battery will have less stored energy)
5) Low tire pressure
6) Tires with higher rolling resistance (maybe snow tires)
7) Any roadway that isn't both a hard surface and dry (standing rain, snow, sleet, etc will dimish range)
8) Increased aerodynamic drag (roof rack, etc)



102 miles range up a 6000 foot pass at 65mph STEADY SPEED (the speed doesn't vary, with cruise control ON).

Your consumption rate on the dash will be 2.5 miles per kWh (assuming you reset it at the bottom, that is, then it will be 2.5 miles per kWh (388 wattHours per mile).

 

[sanders1]

Amazing! Thank you again!

 

[sanders1]

So... I made the trip with no stops and more than a quarter of a standard charge to spare! (22 miles left on the estimated range.) To be safe, I kept my speed around 60-65 on Hwy 210 and then used the cruise control often to maintain speed going up the mountain. While at the cabin I recharged on a 110 plug for about 30 hours back up to a full charge. In hindsight I should have only charged it back up to a standard charge as I got no benifit from driving down the mountain since my battery was full. (Next time.) I love this car.

 

[dstjohn99]

In hindsight I should have only charged it back up to a standard charge as I got no benifit from driving down the mountain since my battery was full. (Next time.) I love this car.

I've not taken a long down grade with the Rav yet. I am interested to see how the bars and range change with the SOC increasing due to regen. I imagine it will be just like chargiung, but IDK with this quirky GOM and software.

 

[Michael Bornstein]

I've done it in my Chevy Volt. I mistakenly fully charged it before leaving Arrowhead. When I reached the bottom, the GOM showed a range of over 60 miles. Of course the true range was more like 38 miles. What happens is that the GOM sees how much battery you've use (none) and how far you've gone (maybe 10 miles) and then calculates how much further you can go. Similarly, coming off the Grapevine in the Volt, I'll start with a range of 17 miles (coming off Mountain Mode), and it will reach 24 or so miles at the bottom of the hill. Surprisingly, it keeps on rising to over 30 miles by the time I turn on to I-5 at the intersection with CA-99, before it starts dropping again. That stretch of I-5 is actually a slight downhill and I use almost no power to go the distance. I am not however getting any regen either, but the GOM keeps rising. The distance from the bottom of the Grapevine to my house is 33 miles, but I usually run out of battery power about 2 miles from my house.

I assume the RAV has a similar algorithm.

I guess what I am trying to say is that you shouldn't trust the GOM after coming off a long hill. (should you ever trust the GOM?) Count bars instead to get your effective range.

 

[Tadol]

My folks have a house out at Dillon Beach, and I found the easiest thing was to install a 220v plug in the garage and get a Jesla from Tony. Charges quick and don't have to think about it -

 

[hino]

I live in Anaheim Hills and have a cabin near lake arrowhead.
This weekend I made a day trip to the cabin.

132 miles available after extended charge
*Fwy91 > 215 > 210 > 18 exit > 40 miles & 40 miles used (92 miles left)
*18 > 189 > cabin (5000' high) > 17 miles & 42 miles used (50 miles left)
As you see RAV4 used 5 miles extra to go up 1000'
5 miles x 5 (5000') + 17 = 42 miles

Coming back
*cabin > 189 > 18 > 210 entrance > 17 miles & 8 miles gained (58 miles left)
*210 > 215 > 91 > Home > 40 miles & 40 miles used w/ac (18 miles left)

 

[fooljoe]

One thing I've noticed about the Rav's GOM that sets it apart from other EVs (at least the one in my Leaf) is that it seems to use a pretty much fixed miles/kWh for each charge (possibly based on your last few drives before that charge.) So with hino's drive we might assume that his driving history led to an assumption of roughly 3.16 miles/kWh (132miles/41.8kWh). Then we might convert his trip report to more meaningful metrics:

40 miles driving to the 18 exit: 12.67 kWh used
17 miles driving up to 5000': 13.3 kWh used
17 miles back down to 18 exit: 2.53 kWh gained
40 miles back home: 12.67 kWh used
Net: 114 miles driven, 36.1 kWh consumed

This shows that about 7.9 kWh, or about 1.6 kWh per 1000', were used (or gained - surprisingly the same for this trip) for the elevation change. This fits pretty well with Tony's range chart, which suggests assuming 2 kWh extra consumption for each 1000' increase and 1 kWh recapture for each 1000' decrease.

Remarkably, despite all the up and down the GOM seemed to be pretty much spot on for your trip. However, as a note to hino or anyone else making a trip report like this: The numbers you report would be incredibly more useful to other drivers (and to yourself while making the trip) if instead of showing GOM miles you were to reset your trip odometer and efficiency meter at the beginning of the drive and show the car's reported miles driven and miles/kWh, which together will give the best possible estimate of kWh used (unless of course you use RavCharge and just report your SOC or kWh directly from that )

 

[fromport]

The numbers you report would be incredibly more useful to other drivers (and to yourself while making the trip) if instead of showing GOM miles you were to reset your trip odometer and efficiency meter at the beginning of the drive and show the car's reported miles driven and miles/kWh, which together will give the best possible estimate of kWh used (unless of course you use RavCharge and just report your SOC or kWh directly from that )

I have done a 12 day trip from so-cal to Oregon (into washington actually) and back.
I am busy in putting together info regarding my trip in a blog.
So far I have documented the first 3 days:

Day1
http://evtrips.blogspot.com/2015/05/day-1-of-12-oregon-trip-junjul-2015.html
Day2
http://evtrips.blogspot.com/2015/06/day-2-of-12-oregon-trip-may-31.html
Day3
http://evtrips.blogspot.com/2015/06/day-3-of-12-oregon-trip-june-1st.html

I should have enabled ravcharge of course for the free test period.
That would have given more info ;-)
I later also regretted not recording the trip using google tracks or something.
That would have added information like altitudes and average moving speeds etc.

 

[TonyWilliams]

This shows that about 7.9 kWh, or about 1.6 kWh per 1000', were used (or gained - surprisingly the same for this trip) for the elevation change. This fits pretty well with Tony's range chart, which suggests assuming 2 kWh extra consumption for each 1000' increase and 1 kWh recapture for each 1000' decrease.

Yes, if you reset both the consumption meter and trip miles meter at the beginning of the trip, the actual kWh burned will be EXACTLY the product of:

Miles driven / consumption rate = BMS reported kWh burned

142 / 3.4 = 41.8kWh burned

Toyota / Tesla doesn't manipulate this data.

*********

Climb energy required:

One kilowatt hour = 2,655,224 pound feet of energy.

Driving your 4000 pound electric vehicle (like an empty RAV4 EV) up a 1000 foot elevation requires 4000 * 1000 = 4,000,000 foot pounds of energy divided by 2,655,224 equals 1.5kWh of energy to lift the car. So, very likely 1.6kWh for a lightly loaded RAV4 EV.

The "Rated Range" (at the default 3.5 miles per kWh) would be:

3.5 * 1.6kWh = 5.6 miles lost per 1000 feet elevation gain

At a higher, and more typical consumption rate of 3.0:

3.0 * 1.6kWh = 4.8 miles lost


Nissan LEAF

1.5kWh of energy at an economy of 4 miles per kWh (250 watts per mile) = 6 miles of range used to drive up 1000 feet for a Nissan LEAF type car.

For a 5000 pound Tesla Model S (just two occupants) equals 5 million foot pounds to go up 1000 feet.


TESLA Model S

5 million divided by 2,655,224 equals 1.883kWh of energy to lift the car.

1.833kWh of energy at an economy of 3 miles per kWh (333 watts per mile) = 5.5 miles of range used to raise the car 1000 feet.

*****************

 

[fooljoe]

if you reset both the consumption meter and trip miles meter at the beginning of the trip, the actual kWh burned will be EXACTLY the product of:

Miles driven / consumption rate = BMS reported kWh burned

142 / 3.4 = 41.8kWh burned

Yup - the only problem I have with this approach is that the dash instrumentation doesn't give enough significant digits. "3.4" miles/kWh displayed on the dash could mean anything from 3.35 to 3.449 miles/kWh, which for a 100 mile drive could result in your actual consumption being just about anywhere in the 28-29 kWh range. Of course this isn't a big deal in most cases, but being off by up to a full kWh can easily result in you coming up a couple miles short of your destination if it's close!

RavCharge improves upon this somewhat by allowing you to derive your actual consumption by taking the difference between your before and after SOC readouts, and by giving you the ability to instantaneously measure your SOC at a much higher fidelity than the bars in the dash provide, but unfortunately it's limited in what it can do when your SOC is above the "100% of normal" range. An optimal solution would be something like LeafSpy for the Rav that can read high-fidelity SOC info direct from the CAN bus, but unfortunately we're not there yet. Anything's better than looking at GOM miles!

 

[TonyWilliams]

An optimal solution would be something like LeafSpy for the Rav that can read high-fidelity SOC info direct from the CAN bus, but unfortunately we're not there yet. Anything's better than looking at GOM miles!

Well, if "we" excludes me... the BMS data is up to three decimal places.

Every JdeMO is built in with the capability to export all this data... a plug-n-play dash mount solution for next year.