How long does it take for a full charge using 110?

[Baxterdown]

Hey guys, I'm going camping in August. We're staying in a cabin at the campsite. My plan is to charge the car using a regular outlet in the cabin. Assuming we'll get there with little to no range left, anyone knows approximately how long will it take to get a full charge? I have a 2017 MX 90D.

I had read somewhere (I might be mistaken) that charging at 110 gives about 4kw per hour. My battery's capacity is 257 miles. So, do I divide 257 / 4? Which would be 64 hours or 2.6 days. I might be completely wrong on how to do the calculation LOL!

We arrive on Thursday and leave on Monday. The car will be parked the 4 days. I just want to make sure I'll have a full charge when we leave on Monday.

Thanks for your help.

Jose

 

[TLej]

My 90D model S charges at about 1% per hour on a 15A 120V outlet. It is sloooooooow, but if you have the time to just let it sit and charge it's easily do-able. I've done it many, many times.

To figure out the wattage, multiply the voltage times the amperage - 15 x 120 = 1800, which is 1.8 kW. Charging isn't 100% efficient so you're actually putting less than that in the pack. Your pack is something like 82 kW of useable capacity, maybe less now that it's older, so you can figure out the rough math.

 

[George3]

If your home/cottage has 240VAC service, then you can cut the charging time at least in half. If the building does not have a convenient 240 VAC outlet, you can tap two opposite phase 120V outlets to create a 240V source. You may be able to tap two 20 amp circuits to further increase the wattage. But you will need a special extension cord for that.

Note that you should not draw the full rated amperage of a circuit; generally limit the current to about 80%. Thus, a 15A, 120V circuit will provide about 1.4 kWatts: 120V * 20A * 80% / 1000 = 1.44kW.

 

[jmaddr]

It’s gonna be brutal. Model X does about 2 miles per hour on 15A/120.

Mobile Connector | Tesla Support

Mobile Connector is useful when you’re away from home and on extended trips. View the charging speed based on your model and adapter.

www.tesla.com

So if you have 257 miles capacity, you need about 128 hours (more than 5 days) for a 0-100. If it’s cold or if you have sentry, cabin overheat protection, etc, enabled, it may be even longer.
See how far the closest supercharger is and if it’s, say 50 miles away, you will need two days to charge.

 

[bob_p]

A few comments...

Charging should provide around 3 miles of range per hour on a standard 110 outlet. A 110 outlet on a 15A circuit can provide around 1.3KWh of charger per hour (charging amps should be limited to 80% of the circuit breaker rating).

Even with 257 miles of rated range, since it's good practice to charge up to 90% and not discharge below 10% - so worst case, you're probably trying to recharge around 205 miles of rated range - which should take around 68 hours. Though it's likely this is a worst case, and the 90D will need less charge.

But even in the worst case, the 90D should be fully charged before 3 full days of charging.

However...

Pulling a continuous load on the 110 outlet could pose challenges - especially if there are any devices sharing that circuit - which could require lowering the charging rate so the breaker doesn't get thrown if another device starts using the same circuit.

And then there's the total power provided to the cabin. If there are multiple circuits, with heavy power use devices such as microwave, electric cooktop/oven or an air conditioner - the total load might be at risk of exceeding the total power available for the cabin.

Odds are - it will be OK. But there may be some cases where continuous power consumption for charging could pose a problem if the power provided to the cabin was already marginal...

 

[Baxterdown]

OMG! Thank you guys for all the replies!!! As it turns out I was at a pool party today and mentioned the camping trip to a friend who’s been wanting to drive my car. He proposed we swap that weekend. I said yes! So, I’m gonna drive his big ‘ol comfy SUV to the campground and he’s gonna cruise around town for a few days in my spaceship.

It’s a win-win!

Based on all your comments and my recent experience with extended highway driving I think I would have had to supper charge twice on the 204 mile trek there and then there’s the stress of “is the car gonna charge all the way” while we were there. Not to mention what @bob_p said. I’m sure there are other devices sharing the circuit in the cabin so I could have end up with more hassle than I’m prepared to deal with.

Thanks again for all your replies. I still have so much to learn about my MX.

 

[peety3]

Get a tool such as A Better Route Planner and get familiar with it. You can easily plug in starting charge levels, ending charge levels, how long you're camping and the charging rate while there, etc. To summarize, your goal is really to supercharge enough so you can comfortably get back to the supercharger.

Though the charging isn't 100% efficient, you can simplify the equation by figuring out your charge rate (80% x 15A x 120V) = 1.4kW and dividing that into your battery size (90kWhr) = 62.5 hours if you were going from zero to 100%. You probably wouldn't get to the campsite at 0%, nor would you really need to leave the campsite at 100%, so you wouldn't need as long. With ABRP, you might want to come up with a plan that assumes no on-location charging, and let any on-location charge be "gravy" for your execution (though alas you have a workaround).

 

[mbp11]

I have a side question: When I charge a significant amount at a supercharger, say, go from 20% to 90%, does the car gain weight? Between the time I arrive and the time I leave, the car seems..... "heavier." Is this due to my imagination or does the change in battery chemistry cause the battery to weight more?

Mike P

 

[nctalkinghead]

I have a side question: When I charge a significant amount at a supercharger, say, go from 20% to 90%, does the car gain weight? Between the time I arrive and the time I leave, the car seems..... "heavier." Is this due to my imagination or does the change in battery chemistry cause the battery to weight more?

Mike P

How much are you eating during that stop

 

[ATPMSD]

When charging on 110v you should to turn off Sentry and Summons modes as these will consume *about* 250 watts / hour. That translates to losing another 20-25% of your charging rate!

 

[Bigriver]

@Baxterdown, in case you want to try the 110 plug-in of your spaceship in the future, I thought I would share my experience with my 100D. I have several relatives I visit that I need to employ this strategy. Time is your friend and I vote that 4 days would have been plenty. Here are some snapshots from Teslafi from a few of my 110 charging sessions. One of these included having to use an extension cord. Note that the losses are relatively high, with the efficiency only in the 70%-ish, meaning that more energy is drawn from the wall than makes it to the battery. Still, my rule of thumb is consistent with what was stated above, the SOC increases about 1%/hour. I usually beat that a bit, as you can see. Oh, and I leave sentry mode on. I haven’t found that matters as the car essentially stays awake to charge.

 

[Baxterdown]

Thanks @Bigriver! Interesting info! 52% in 2 days says I might have been able to fully charge in 4 days. I appreciate your feedback.

Jose

 

[mbp11]

Warning. In my limited experience, make sure you have a large gauge, thick, heavy duty extension cord if you need to use one. The thin and inexpensive cords get really warm!

 

[RichardL]

I have a side question: When I charge a significant amount at a supercharger, say, go from 20% to 90%, does the car gain weight? Between the time I arrive and the time I leave, the car seems..... "heavier." Is this due to my imagination or does the change in battery chemistry cause the battery to weight more?

Mike P

Been discussed before:

Weight of electrons

Main point is not really, since the electrons were already there, they are just moved around

 

[mbp11]

Been discussed before:

Weight of electrons

Main point is not really, since the electrons were already there, they are just moved around

Yes, I know, I was actually being a little silly. Disregard, please!

 

[Richbot]

I charged using a 25' 12 gauge extension cord and the UMC on a wall outlet on a recent cabin trip too. 1% per hour is about right, so we got "back" 12-14% per evening while there, which was usually more than enough to cover the day's driving. We arrived with about 60% charge because we supercharged to relatively high SoC on our way in, just in case that didn't work due to a GFI or something tripping, but it worked great.

Second the ABRP thing too, if you're at all concerned, be conservative with your settings on the app and you'll be pleasantly surprised no matter what the weather does