Help me understand the math.

You have 250 miles of EPA rated range. Not 250 real world miles.

You know what an estimate is right?

Thanks. So the 250mi are ideal conditions, what the navigation map shows what’s actually going to happen for this trip. Thanks.

Correct.

We need a few more details. Are you preconditioning before leaving? What’s the average outdoor temperature of the trip? How are your environmental settings in the car?

I understand the difference now. Example: my trip is all uphill. There is no way it will hit the calculated rated.

Stop trying to understand the math just enter your destinations in the navigation and it will do all the math for you. You’re obviously going to need a charge to make it round trip.

Tesla's range estimate in the car's navigation is usually pretty accurate BUT it will change as driving conditions and speed changes. Wind will affect it and definitely going over 70 affects it.

The batteries full charge range doesn’t change except over time with small depreciations as the battery gets older. The actual REAL WORLD range does and is dependent on so many factors. Temp, weather (rain, snow, wind etc), elevation, driving habits, AC, highways or side streets, load in car and on and on. Route planning takes that all into consideration. Your overall battery % range does not

Yup

You got it! My wife does a 108 mile commute in her MY every day. In the winter we charge to 90% and she arrives home around 20-25%. Summer, we charge to 80% and she gets home in the mid 30%. She is cold natured and loves that heat pump during the winter!

Never look at miles. Only look at percentage.

I’ll stay below 70 then. I believe Chill/Sloth will keep me below 70 from my experience so far.

All uphill? Both ways? When I lived in Colorado, getting there took more, coasting down took less. Even going up, calculations didn't consider the benefits of regeneration. Your in-car estimate is likely assuming for you that you don't want to get to where you are going empty. On the other hand, that may be exactly what you want to do and then charge at home. Math (as in consumption estimates) and AI are there to help, not replace thinking. I would go for it. But if you have concerns, charge it up to 95% before that trip. There's nothing wrong with charging full before a road trip, because you will be using that power. If you still want even more peace of mind, depending on where you are going -- take a mobile charger with you and plug your Y in when you get to where you are going. That will add 30-40 miles overnight (if you are spending teh night where you are going).

Thanks.

It depends ENORMOUSLY on how you drive the car. Just like gas. The car computer might see that your route is highway miles and know you always drive over 75mph and knows you’ll have reduced efficiency. Elevation can also affect range. Going uphill on the way there will give you a lower estimate, but you’ll regain it with regen braking coming back. I’ve done lots of experiments on long road trips. I’ll drive a whole “tank” at 70, 60, 55… once you cross 60mph and stay there you immediately lose 10% range and you lose more the faster you go. Same for stop and go traffic under 10mph. I’ve had the computer tell me I wasn’t going to make it, -4% at arrival, so I slowed down to 45mph and made it with 2% left. Also, the route planner knows you’re probably starting at 80% and wants to charge at around 10% lowest. You could intentionally charge to near 100% right before leaving, keep the speed low, keep the AC reasonable, and make the trip on one charge.

They don’t.

In my experience crossing multiple mountain ranges, you’ll regain the extra range used to go uphill on the return going downhill.

Yep, and Tesla is the only car company that does this (showing EPA rated range) as far as I know. Every other EV I've driven gives you an estimated range based on your recent driving, which I think makes more sense (it will be lower if it's cold outside or you drive like a maniac).

Just supercharger for 15 min. Sould be good to go

Tesla’s range estimates also account for elevation changes. When you drive uphill, energy consumption increases; when you drive downhill, consumption decreases due to gravity and regenerative braking. If you enter a destination, the navigation screen shows the estimated battery usage for the trip. At the bottom of the directions list, you can also see the projected energy and charge level for the return journey.

The 250 mile range estimate at the top of the screen is not affected by outside conditions, speed, etc. if you’re looking for a range estimate based on your driving, click the green graph icon at the bottom of your screen (might have to click the three dots for all apps to appear) and that figure will be a better estimate. You can also change it to use data from the last 10, 100, or 200 miles.

You can charge to 100% for your trip

Charge to 100%. Make sure your tires have 47PSI. Drive behind a semi truck or bus or something big that can block the wind and tail them as long as you can. You'll get there over 50% for sure, and you can judge if you just need a little 5 minute top off sometime on the way home! 100% charging before long trips is recommended/almost required in my mind!

This is the way. Use battery %, then use miles on trip planner/nav.

Oh yeah if its uphill and you get there with 50% you are fine for the trip home! Going downhill will take much less.

Winter time, 75% roughly is what you will get. Summer time with no ac you might get 115%.

Sloth drives at the posted limit

You’re missing research. Obviously you did none before buying.

I don't think the app shows an option for round trip, but you can edit it and see if you can actually make it round trip. Inside the car it usually also shows a round trip estimate

Tessie calls this "range efficiency" — how much does the estimated range change vs actual miles driven. It is almost never 1:1 based on their real-world data for both. [https://help.tessie.com/article/59-driving-efficiency](https://help.tessie.com/article/59-driving-efficiency)

I made it with 46% left✌️

True to all you said.

EPA estimated range is completely in non realistic conditions

Charge to a 100 just before you leave

That’s exactly what I said.

In theory, theory and practice are the same, but in practice they are not.

Upvoted for energy math. So the app said you'd arrive with 24% remaining, but you actually arrived with 46%? That's a huge difference.

Yeah huge difference. The way back consumed the same. I drove on FSD Sloth so the car took its time. I believe that made a huge impact.

Which is kinda crazy considering really thats what most people should be doing anyway haha

Did you make it back?

I charged a little just to be safe, but I could have made it back yes.

I’m not sure why this is so confusing, it’s the same as gas, drive faster harder you use more, same with electricity.

It’s not confusing. But gas cars give you one estimate of how much you can drive. Teslas give you two estimates.

my car only give me 1 estimate, not 2, never has

What car do you have?

2 Model Y's and a Model 3