edatoakrun
Well-known member
http://www.jurassictest.ch/GR/" onclick="window.open(this.href);return false;
The tool above was posted recently by GRA here:
http://www.mynissanleaf.com/viewtopic.php?f=31&t=5425&start=50" onclick="window.open(this.href);return false;
Only a few, mixed reports of it's accuracy so far. Since it looks promising to me, I thought a dedicated thread for anyone using it,to discuss how you use it, and how well it works, might be worthwhile.
I've just been looking back at my past driving by CW records and comparing to this tool, and there is a close correlation in the results.
But, it is impossible for me to exactly reproduce my past CW driving records with this tool, for two reasons.
The first is that Google maps does not recognize the first few hundred yards, and 150 ft. descent on my driveway as a "road" so to more accurately test, I will have to stop and restart at some point “on the map”, to get this segment of my driveway "off the record" of the "trip” reported by CW, on the "electric rate simulation".
The tool also chooses it's own default rout, and doesn't seem to let me alter it. So it has me take a parallel rout to my most frequent destinations,
However, since the Ascent and descent totals, grades, and miles driven, are very similar, and am able to specify the same speed, the two routes should have similar kWh use results, from the two sources.
They do. In fact, all results seem to be within the uncertainty I'd expect, simply due to my inability on any drive, due to road and traffic conditions, to maintain a anything close to a constant speed, or estimate the average with great accuracy.
Not only does it seem to me,to be, at least fairly accurate, for the entire days driving consisting of the two-way trip, but the ascent and descent directions, which are recorded as separate trips, on CW on the "electric rate simulation" page, also seem to be reproduced by this tool, accurately, always within the percentage of variation, I’d expect from speed variation and uncertainty
It will be difficult for me to verify just how close the tool matches real-world results.
From both directions from my home, the tool’s embedded Google map directs me to highway 299, rather than the shorter routes with less speed variation I normally choose to drive.
So for me to use it, on all trips from my home, I will have to match my route to that the tool chooses, routes with large speed variations, putting a large uncertainty into the full test, due to the difficulty estimating an "average" speed. And since I will have to drive much of the trip at under 30 mph, and much at over 50 mph. So I will only be able to test a short segment of a larger trip, at near-constant speed, never over close to a 100% charge range.
Obviously, the predictions could be much more accurately tested by others, who could do as close to a steady-speed drive, over a long distance, with significant ascent/descent, and repeat it, to get a larger sample for real world average results.
Some other factors and uncertainties you may want to consider, and resolve.
The first, DO NOT use the LEAF estimate of average speed, without adjusting for your actual speed while driving. The car includes every stop light, and the speed you back out of your garage, as part of this average, though they have little effect on the driving efficiency of your tip, overall.
Small differences in your estimate of average speed have large result, both in real life, and in the range prediction the tool provides.
I don’t know exactly how accurate CW kWh consumption reports are. I use them, since they seem to consistently and accurately replicate range results for me, and no one with accurate SOC info, has reported either constant or variable errors in them. You can of course, check the tool against any other method you currently use, to estimate your range.
Of course, the best test, is to use the tool to plan a near 100% battery capacity future trip, and see what your results are.
My car does have a 2.5% constant under-reporting error in CW miles driven. Most others who have checked, seem to report the same thing, but you should definitely check CW against your odometer as well as mile as reported on the tool site. The “Help” page there also suggests it’s own inaccuracies for “tortuous” routes, so I’d suggest an independent check of trip miles, from another source, especially if your route has a lot of winding roads.
The tool has a default value of 21 KWh (which you can adjust) I suspect ABC would be closer to 20 kWh at 100% charge, at my current battery temperatures. No accurate account of available battery capacity, in kWh, adjusted for battery temp, is yet available. So you should never expect range predictions from this tool, any more accurate, than your estimate of ABC, before you begin your trip.
The tool above was posted recently by GRA here:
http://www.mynissanleaf.com/viewtopic.php?f=31&t=5425&start=50" onclick="window.open(this.href);return false;
Only a few, mixed reports of it's accuracy so far. Since it looks promising to me, I thought a dedicated thread for anyone using it,to discuss how you use it, and how well it works, might be worthwhile.
I've just been looking back at my past driving by CW records and comparing to this tool, and there is a close correlation in the results.
But, it is impossible for me to exactly reproduce my past CW driving records with this tool, for two reasons.
The first is that Google maps does not recognize the first few hundred yards, and 150 ft. descent on my driveway as a "road" so to more accurately test, I will have to stop and restart at some point “on the map”, to get this segment of my driveway "off the record" of the "trip” reported by CW, on the "electric rate simulation".
The tool also chooses it's own default rout, and doesn't seem to let me alter it. So it has me take a parallel rout to my most frequent destinations,
However, since the Ascent and descent totals, grades, and miles driven, are very similar, and am able to specify the same speed, the two routes should have similar kWh use results, from the two sources.
They do. In fact, all results seem to be within the uncertainty I'd expect, simply due to my inability on any drive, due to road and traffic conditions, to maintain a anything close to a constant speed, or estimate the average with great accuracy.
Not only does it seem to me,to be, at least fairly accurate, for the entire days driving consisting of the two-way trip, but the ascent and descent directions, which are recorded as separate trips, on CW on the "electric rate simulation" page, also seem to be reproduced by this tool, accurately, always within the percentage of variation, I’d expect from speed variation and uncertainty
It will be difficult for me to verify just how close the tool matches real-world results.
From both directions from my home, the tool’s embedded Google map directs me to highway 299, rather than the shorter routes with less speed variation I normally choose to drive.
So for me to use it, on all trips from my home, I will have to match my route to that the tool chooses, routes with large speed variations, putting a large uncertainty into the full test, due to the difficulty estimating an "average" speed. And since I will have to drive much of the trip at under 30 mph, and much at over 50 mph. So I will only be able to test a short segment of a larger trip, at near-constant speed, never over close to a 100% charge range.
Obviously, the predictions could be much more accurately tested by others, who could do as close to a steady-speed drive, over a long distance, with significant ascent/descent, and repeat it, to get a larger sample for real world average results.
Some other factors and uncertainties you may want to consider, and resolve.
The first, DO NOT use the LEAF estimate of average speed, without adjusting for your actual speed while driving. The car includes every stop light, and the speed you back out of your garage, as part of this average, though they have little effect on the driving efficiency of your tip, overall.
Small differences in your estimate of average speed have large result, both in real life, and in the range prediction the tool provides.
I don’t know exactly how accurate CW kWh consumption reports are. I use them, since they seem to consistently and accurately replicate range results for me, and no one with accurate SOC info, has reported either constant or variable errors in them. You can of course, check the tool against any other method you currently use, to estimate your range.
Of course, the best test, is to use the tool to plan a near 100% battery capacity future trip, and see what your results are.
My car does have a 2.5% constant under-reporting error in CW miles driven. Most others who have checked, seem to report the same thing, but you should definitely check CW against your odometer as well as mile as reported on the tool site. The “Help” page there also suggests it’s own inaccuracies for “tortuous” routes, so I’d suggest an independent check of trip miles, from another source, especially if your route has a lot of winding roads.
The tool has a default value of 21 KWh (which you can adjust) I suspect ABC would be closer to 20 kWh at 100% charge, at my current battery temperatures. No accurate account of available battery capacity, in kWh, adjusted for battery temp, is yet available. So you should never expect range predictions from this tool, any more accurate, than your estimate of ABC, before you begin your trip.