Which Rated Range is Correct/Reliable?

[caddieo]

Excuse me if this has already been answered, but I have not yet been able to find it. Before I embark on a long trip, I would like to clarify which rated range number is reliable for trip planning - or more importantly - for trip management. I have noticed that the rated range in the dash (inside the speedo) can be as much as 10 to 30 miles higher than the rated range in the energy graph using the average mode. In the instant mode, the wide and frequent fluctuations due to speed changes drive me nuts.:crying: Which one do you rely on more for relief or aggravation of range anxiety - the dash or the energy graph? Thanks in advance for your answers.

 

[dsm363]

The rated range on your energy chart/app is based on the instant/average of the last 5, 15 or 30 miles. The rated range on the odometer is more like the 'fuel' gauge and tells you how much energy you have left. This doesn't guarantee you'll be able to go as far as the number of miles it says (it is based on the EPA 5 cycle test). Basically, if you pick average over the last 30 miles, that number should be higher than the miles you have left on the odometer. If you can manage to keep your Wh/mile in the low 300 range you'll get close to your rated range on the odometer.

 

[ken830]

The energy graph is an estimate based on the last 0.1, 5, 15, or 30 miles. The rated range that you see on your dash is based on the remaining charge left in your battery.

 

[caddieo]

The rated range on your energy chart/app is based on the instant/average of the last 5, 15 or 30 miles. ............. Basically, if you pick average over the last 30 miles, that number should be higher than the miles you have left on the odometer. If you can manage to keep your Wh/mile in the low 300 range you'll get close to your rated range on the odometer.

I think you may just have given me the clue that I needed. I have been using the chart with the 5-mile setting. I'll try it at the higher settings and if that works out as you predicted, then this thread is done - unless there are some other/better ideas out there.

 

[GlennAlanBerry]

After having a Model S for a couple of months, I would think you would start to have a feel for how you typically drive and how you do compared to the rated range under different driving conditions. I just try to pay attention to my mileage and energy usage/mile since the last charge vs. what my rated range was to begin with and what it is as I continue to drive. This helps me figure out whether I am doing better than rated range or worse than rated range. Driving just a little slower makes a huge difference on trips, but there are so many other factors such as elevation change, wind, rain, temperature, etc. that are going to affect your range.

Watching the energy graph is not really that helpful, IMO.

 

[dsm363]

Watching the energy graph gives you an idea at least if you are wildly off the mark. I believe rated range is around 308 Wh/mile so you should get close to the rated range if you keep it there.

 

[caddieo]

After having a Model S for a couple of months, I would think you would start to have a feel for how you typically drive and how you do compared to the rated range under different driving conditions.

I may have had the car for a couple of months but I have been traveling over the past 3 and a half weeks and just resumed using the car yesterday. Whatever feel I had developed over the first month of driving has been obliterated by over 2000 miles of ICE driving since 8/28. When feel goes you start relying on other things - e.g. I have probably lost some feel for my golf swing over the same interval and anticipate that I am going to very mechanical and "by the numbers" for the first few rounds.:tongue:

 

[jerry33]

While the rated range is interesting, because sometimes stuff happens, the best plan on a trip is to make the charging stops frequent enough that you never have to worry about it. Generally 150 miles is a good number. It won't take any longer as you don't have to charge as much at each stop.

 

[ChadS]

In my signature is a link to a post that has a lot of trip-planning info. The short of it, though, is basically what jerry33 says - just don't plan your charging stops too far apart. The number I use is 177 miles. Then you never have to worry about using HVAC, how fast you go, elevation changes, headwinds, etc. Easy peasy.

(Of course you can skip a charging stop - or more likely, just cut it short - if you are doing well and don't need it).

 

[Larry Chanin]

Hi Archie,

At the risk of stating the obvious, what I do is make sure that the rated range on my speedometer is always greater than the miles remaining on my navigation display. :biggrin:

On long trips periodically I use the energy chart to check whether my driving (projected range) is better or worse than the rated range as shown on the speedometer. (As dsm explained the rated range is based on the driving conditions used by EPA to conduct their 5-cycle tests.) On long trips for Projected Range I use the average for 30 miles. On long trips I recommend using cruise control in range mode. If it is a really long distance between charging, I will set my cruise to about 64 mph. I find that with the A/C on this will give me projected range at rated range or better.

Larry

 

[caddieo]

Thanks to everyone. I got more than I expected!! :biggrin:

 

[ToddRLockwood]

I've recently turned over 10K miles. After numerous trips I've come to the following conclusion: Rated Range (displayed below the speedometer) is more or less equal to driving 65mph with cruise control, on a flat, level interstate with no wind. On a hilly interstate, you might find that Rated Range equates closer to 60mph.