Forget the GoM: Range Plan like a Pro

[TheBigBezo]

I've done a few serious 2,000+ mile trips so far and one thing I realized is that the GoM isn't that helpful, not for road trips at least. Reading other posts here, I wasn't alone.

But what if I told you there is a 100% sure fire way to know if you can make it somewhere. No guessing, but it does involve some math.

Let's take a recent example I did, I was at 100% and needed to drive 230 miles. My GoM said 346 miles (lol), can I make it? Well like many have seen, that's a guess . But let's take that distance and divide it by my current energy state (131kWh). That's 1.8 miles/kWh, manageable on the highway. So I know without a doubt if my trip efficiency stays above that I'll make it. Using either the trip screen notification bar thing under Android Auto on the center screen or the trip report in the instrument cluster I can monitor how I'm doing. I typically get 2.1 miles/kWh at 70mph and 1.7-1.8 at 80mph. I know it's doable now, but what if driving conditions change? Well you can do the math in the truck especially if you just ask Google/Siri; at 50% (65.5 kWh) charge with 100 miles to go you know you'll still make it. If that new number is higher you can either charge early or slowdown etc, and if that number is lower (because you're more efficient) you can then do things like speed up.

Kinda wordy, but I have used this process to really max perform my range (90 - 10%). Do make sure your destination charger works though, there's not much slop if you want to use every ounce of trons you have.

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[mb0220]

This is well-stated, in my opinion. Have a good base of knowledge in how your vehicle performs in various circumstances and you should be able to set your own reasonable expectations based on the math you pointed out.

To that I would only add that I have noticed the range estimate does appear to function much better when navigating with the native app, as opposed to (Google Maps or Waze). Although it does appear to select unusual routes, but this might be an attempt to maximize efficiency.

 

[luebri]

Based on my 10k experience and temps between -10F and 95F I came up with a quick cheat sheet.

Print, laminate, and place on dash! Watch your MPK as you drive and calculate in your head accordingly!

 

[Refactoringdr]

Here’s my math I use. I usually keep the truck charged to 80%. 80% of 131kWh is real close to 100kWH. So if I’m getting 2.1 mi/kWh, I can go 210 miles. I can do that in my head. If I start at 100%, I just add in another 1/4 of the distance, so I would add another 52 miles=262 miles total. None of this is exact, but I can do most of it in my head and it’s errs on the short side.

 

[Maxx]

I have a standard pack. I heard my pack in 98KWh so I always assumed I have roughly 1 KWh for every % SOC but when I plugged in the scanner, I realized available power is a lot less. At 70% displayed SOC, the actual SOC is 64.99% and energy available is 59.58 KWh so now I deduct 10 from the SOC I see and then go by efficiency numbers to do a fast rough calculation of how much range I have.

 

[GoodSam]

quick cheat sheet

@luebri Beautiful...Would you be so kind as to attach your spreadsheet file so I can make one up for my SR? What do you think range is at 90+F?

 

[TheWoo]

I have a standard pack. I heard my pack in 98KWh so I always assumed I have roughly 1 KWh for every % SOC but when I plugged in the scanner, I realized available power is a lot less. At 70% displayed SOC, the actual SOC is 64.99% and energy available is 59.58% so now I deduct 10 from the SOC I see and then go by efficiency numbers to do a fast rough calculation of how much range I have.

98kWh is still right. When your scanner shows 64.99%, that's of the gross kWh, which is larger than 98kWh. And the available is less than actual, because there is buffer built into the bottom of the battery.

 

[TheBigBezo]

@luebri Beautiful...Would you be so kind as to attach your spreadsheet file so I can make one up for my SR? What do you think range is at 90+F?

While I don't have a spreadsheet, I found air conditioning using considerably less power. At 100F+ on road trips I was 98% power from driving, 2% accessories/AC. IMHO, truck is much better suited to heat than cold which fortunately I live by the gulf coast where it's a rare day to be below 60F.

 

[luebri]

@luebri Beautiful...Would you be so kind as to attach your spreadsheet file so I can make one up for my SR? What do you think range is at 90+F?

90+ would start to see some degradation, but not a lot

 

[TheWoo]

While I don't have a spreadsheet, I found air conditioning using considerably less power. At 100F+ on road trips I was 98% power from driving, 2% accessories/AC. IMHO, truck is much better suited to heat than cold which fortunately I live by the gulf coast where it's a rare day to be below 60F.

The air conditioner is significantly more energy efficient than the heater. I don't even worry about running the A/C in the summer. Has little overall impact on range.

 

[Maxx]

98kWh is still right. When your scanner shows 64.99%, that's of the gross kWh, which is larger than 98kWh. And the available is less than actual, because there is buffer built into the bottom of the battery.

I still don’t see how math works for these numbers. 59.58 KWh is the energy available.. May be my battery health (98.5%) or cold is throwing off the numbers a bit.

 

[TheBigBezo]

I have seen a number of posts with new users about range anxiety so I figured it would be a good time to bump this thread.

Today, on my drive home, I had no chargers on my route. I had 73 miles to go and my GoM said I had 78 miles. Was I worried? No.

I used the techniques in this thread to calculate my min efficiency to continue which turned out to be 1.65mi/kWh. I reset my trip meter and monitored it, seeing I was hovering around 2.1 and doing about 65mph. It's simple thermodynamics at that point, and since I knew I was beating my minimum efficiency I kept driving with confidence and arrived home with 6% left. At no point did I need to slow down or disable HVAC.

I want to share this info again and answer ant lly questions because once folks understand this it completely removes any 'guessing' from the drive. You know 100% if you have the distance or not.

 

[MM in SouthTX]

I've done a few serious 2,000+ mile trips so far and one thing I realized is that the GoM isn't that helpful, not for road trips at least. Reading other posts here, I wasn't alone.

But what if I told you there is a 100% sure fire way to know if you can make it somewhere. No guessing, but it does involve some math.

Let's take a recent example I did, I was at 100% and needed to drive 230 miles. My GoM said 346 miles (lol), can I make it? Well like many have seen, that's a guess . But let's take that distance and divide it by my current energy state (131kWh). That's 1.8 miles/kWh, manageable on the highway. So I know without a doubt if my trip efficiency stays above that I'll make it. Using either the trip screen notification bar thing under Android Auto on the center screen or the trip report in the instrument cluster I can monitor how I'm doing. I typically get 2.1 miles/kWh at 70mph and 1.7-1.8 at 80mph. I know it's doable now, but what if driving conditions change? Well you can do the math in the truck especially if you just ask Google/Siri; at 50% (65.5 kWh) charge with 100 miles to go you know you'll still make it. If that new number is higher you can either charge early or slowdown etc, and if that number is lower (because you're more efficient) you can then do things like speed up.

Kinda wordy, but I have used this process to really max perform my range (90 - 10%). Do make sure your destination charger works though, there's not much slop if you want to use every ounce of trons you have.

This is what I do if I go on the road. Always recalculating and resetting the trip odometer. If I get off the back roads and on a highway with 43% of my ER battery remaining, and I have 100 miles to go, I start doing the math. 43% of 131 means there is 56 kWh remaining. 56 x 1.7 is only 95 miles. Not gonna make it. 56 x 1.8 is 100.8. Just barely gonna make it. Time to slow down and draft. So then I log some miles at 1.9 or 2.0, reset, and see what my buffer is again and whether I can get out from behind the trucker.

 

[Newton]

The guess-o-meter is really bad. I just did an 800 mile trip on a SR Lariat and would have been freaked out if I was not familiar with electric cars. Once I lost a significant amount of GOM range simply by adding a rest stop to the route, which makes no sense at all. (It was just 1/2 mile off of I-5 so it would not involve a terrain adjustment.) Another time just looking at possible destinations in the nav caused the range to drop. Seriously, Ford, what is up with that? I could drive miles towards my destination without the GOM dropping at all simply because it was trying to catch up with its bad guess of range.

So my trick is pretty much the same as others here (and how I drive EVs anyway.) I reset Trip 2 every time that I charge and watch the miles/kWh. I have a chart for the standard range battery with miles left to a 10% reserve. If I'm pushing the range (and I did) I'll consult the chart. I came in at 14% on my last two stops with power slightly reduced and orange on the gauge. It worked fine.

For those who have not done this, the truck gets upset when it thinks that you have less than 30 miles of range and turns the gauges orange. That is all that happens. I did notice that the poweer part of the gauge showed power reductions to 90% when the SoC got to 20% or so but it had no noticable effect.

Here is my chart. Use at your own risk. Interestingly, on the trip down I-5 from Washington to Oregon I got a lot better range than I have been experiencing around town. I averaged 2.3 mi/kWh and on one leg got 2.5!

 

[invertedspear]

The guess-o-meter is really bad. I just did an 800 mile trip on a SR Lariat and would have been freaked out if I was not familiar with electric cars. Once I lost a significant amount of GOM range simply by adding a rest stop to the route, which makes no sense at all. (It was just 1/2 mile off of I-5 so it would not involve a terrain adjustment.) Another time just looking at possible destinations in the nav caused the range to drop. Seriously, Ford, what is up with that? I could drive miles towards my destination without the GOM dropping at all simply because it was trying to catch up with its bad guess of range.

So my trick is pretty much the same as others here (and how I drive EVs anyway.) I reset Trip 2 every time that I charge and watch the miles/kWh. I have a chart for the standard range battery with miles left to a 10% reserve. If I'm pushing the range (and I did) I'll consult the chart. I came in at 14% on my last two stops with power slightly reduced and orange on the gauge. It worked fine.

For those who have not done this, the truck gets upset when it thinks that you have less than 30 miles of range and turns the gauges orange. That is all that happens. I did notice that the poweer part of the gauge showed power reductions to 90% when the SoC got to 20% or so but it had no noticable effect.

Here is my chart. Use at your own risk. Interestingly, on the trip down I-5 from Washington to Oregon I got a lot better range than I have been experiencing around town. I averaged 2.3 mi/kWh and on one leg got 2.5!

Can I interest you in this tool I built: https://lightningcalcs.pages.dev/
Works great on your phone.