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Do you leave the mobile charger plugged in when not in use?

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Wondering if I should just unplug it everytime .. how much energy am I wasting by keeping the plug attached?

Thanks

Not sure what your are describing. Is the UMC still attached to the power source? If it's not, is the remaining just lying around (to potentially get damaged)? You will not lose any charge/power regardless of the cable being still connected if everything is working as expected...
 
I've only had my car for a week, so please don't take this as wise or sage advice, just items for thought.

Given that others have said there's not trouble from leaving it plugged in, I have a good reason to plug it in: I charge in multiple stages when I get home, and I don't want to go out every time just to turn it on or off. Many of those are scheduled charges. Too bad that I actually have to manually set max amps and change schedule inside the car, because I'd like to set multiple schedule and amps points throughout the day remotely.

For example, here's a rough draft of how I plan to do it:

Background:
My solar system puts out a small amount of power (5.8kWp = 5,800 watts peak power -- I have to find out if this is AC or DC), during the middle of the day. I usually run out and set the Amps on my car to whatever kW my solar is currently outputting minus enough for the house to take the rest, so that I do not use high rate electricity during the day, and I use the solar power as much as possible. Watts=Volts*Amps. kW=KiloWatt=1000Watts. kWh=the amount of energy equal to 1kW for an hour (which you can obtain quicker or slower than one hour, so it is an amount measurement, not a time measurement -- horribly confusing!, but if you are charging at 1kW average, then in an hour, you get 1kWh, and if you are charging at 2kW average, then in 30 minutes, you get 1kWh, or in 60 minutes, you get 2kWh, and so on (e.g., the Alameda Whole Foods I get 40kW at the EVGO Chademo, which allows exactly 30 minutes at $0.10/minute in the $15/month plan, so (30 minutes / 1 hour) * 40kW = 20kWh, and 20kWh at $0.10/minute for 30 minutes is $3 for 20kWh or $0.15/kWh (plus my monthly rate), which is a good way to compare costs to my local charges; most EVGO Chademo are 30kW, so they are $0.20/kWh cost at almost all EVGO in California).

Starting Jan. 10, 2017, our rate at 11PM goes down to around $0.15/kWh, whereas in the day it will be around $0.50/kWh. Charging 11PM-7AM will cost less.

Weekdays workdays at my 6AM-2PM job:
  1. When I get home, I immediately get it up to a safe battery charge, so that it is not damaged at a low state of charge. I do this as soon as possible when I get home, even though the electricity rates are high. If my solar panels are making enough energy, I'll try to use that instead of the local PG&E grid power. I have yet to determine the best % for this, but I'm guessing it is somewhere between 20% and 60% in my "60" that is actually a software limited 75. Your car will be different unless it is the same as mine. I lower the amps used by my car to be about 1kW lower than the output of the solar panels if they are producing a lot.
  2. After charging in step 1, I re-adjust the amps in the car to the max (48 Amps for me) for the overnight charges. Because I might forget this step, I calculate enough minimum % targets so that even if I sleep through this step, I am ok the next day.

    This is where there would be a step 3 (followed by step 4 below) if the car scheduler allowed it. As soon as the grid electricity gets to the good rate, whether this be sunlight or time of use (for me 11PM), I can start the next bunch of charging, to get it closer to the overnight safe zone, but since I am usually in bed, I can't do this. Instead, I just skip this step, making certain that the minimal safe zone was already achieved in step 1.
  3. I set the time schedule in the car to start charging so that I get to 100% at the latest possible moment that I can leave the house and still make it to work on time, without going past the bottom-cost electricity at all (7AM for me, but I have to leave for work no later than 5AM, so I calculate 100% target to be 5AM). If I leave early, I can drive slower, and will have more time to get to intermediary charging stations, so it does not matter that I don't reach 100% if I am so lucky as to be ready to leave before I have to leave. If I leave late, the 100% will be eaten up more quickly by my more active driving, and I'll be stuck in more traffic, so more climate control means more energy use. I set this time every Sunday, calculated for the next weeks' worth of work, and every day that the next day is expected to be different.
Weekends:
  1. When I get home, I get it up to safe battery charge. I also try to make use of the solar panels, without going over. I set the target % and amps max both to work within these constraints.
  2. If the solar gets better, I readjust.
  3. In the evening, I set the amps back up to max. Sometime before the weekend (on Friday, or on the weekend itself), I set the time for charging to once again be during the good cost times (11PM-7AM). I target a safe battery level of around 60%, which in the 60D is the same as around 50%, which is a good spot to leave it long term.
  4. When I wake up the next morning, I determine when, and if, I will go anywhere. If I think I will, then I put the car to whatever % state of charge I want to charge it at, and tell it to start charging.
All the above are done from my room, hundreds of feet away from the car itself, except for changing the amps level. I don't have to unplug or plug in the car. I'm thinking of getting a charger with a pilot in it to make that work better remotely, too.
 
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I've only had my car for a week, so please don't take this as wise or sage advice, just items for thought.

Given that others have said there's not trouble from leaving it plugged in, I have a good reason to plug it in: I charge in multiple stages when I get home, and I don't want to go out every time just to turn it on or off. Many of those are scheduled charges. Too bad that I actually have to manually set max amps and change schedule inside the car, because I'd like to set multiple schedule and amps points throughout the day remotely.

For example, here's a rough draft of how I plan to do it:

Background:
My solar system puts out a small amount of power (5.8kWp = 5,800 watts peak power -- I have to find out if this is AC or DC), during the middle of the day. I usually run out and set the Amps on my car to whatever kW my solar is currently outputting minus enough for the house to take the rest, so that I do not use high rate electricity during the day, and I use the solar power as much as possible. Watts=Volts*Amps. kW=KiloWatt=1000Watts. kWh=the amount of energy equal to 1kW for an hour (which you can obtain quicker or slower than one hour, so it is an amount measurement, not a time measurement -- horribly confusing!, but if you are charging at 1kW average, then in an hour, you get 1kWh, and if you are charging at 2kW average, then in 30 minutes, you get 1kWh, or in 60 minutes, you get 2kWh, and so on (e.g., the Alameda Whole Foods I get 40kW at the EVGO Chademo, which allows exactly 30 minutes at $0.10/minute in the $15/month plan, so (30 minutes / 1 hour) * 40kW = 20kWh, and 20kWh at $0.10/minute for 30 minutes is $3 for 20kWh or $0.15/kWh (plus my monthly rate), which is a good way to compare costs to my local charges; most EVGO Chademo are 30kW, so they are $0.20/kWh cost at almost all EVGO in California).

Starting Jan. 10, 2017, our rate at 11PM goes down to around $0.15/kWh, whereas in the day it will be around $0.50/kWh. Charging 11PM-7AM will cost less.

Weekdays workdays at my 6AM-2PM job:
  1. When I get home, I immediately get it up to a safe battery charge, so that it is not damaged at a low state of charge. I do this as soon as possible when I get home, even though the electricity rates are high. If my solar panels are making enough energy, I'll try to use that instead of the local PG&E grid power. I have yet to determine the best % for this, but I'm guessing it is somewhere between 20% and 60% in my "60" that is actually a software limited 75. Your car will be different unless it is the same as mine. I lower the amps used by my car to be about 1kW lower than the output of the solar panels if they are producing a lot.
  2. After charging in step 1, I re-adjust the amps in the car to the max (48 Amps for me) for the overnight charges. Because I might forget this step, I calculate enough minimum % targets so that even if I sleep through this step, I am ok the next day.

    This is where there would be a step 3 (followed by step 4 below) if the car scheduler allowed it. As soon as the grid electricity gets to the good rate, whether this be sunlight or time of use (for me 11PM), I can start the next bunch of charging, to get it closer to the overnight safe zone, but since I am usually in bed, I can't do this. Instead, I just skip this step, making certain that the minimal safe zone was already achieved in step 1.
  3. I set the time schedule in the car to start charging so that I get to 100% at the latest possible moment that I can leave the house and still make it to work on time, without going past the bottom-cost electricity at all (7AM for me, but I have to leave for work no later than 5AM, so I calculate 100% target to be 5AM). If I leave early, I can drive slower, and will have more time to get to intermediary charging stations, so it does not matter that I don't reach 100% if I am so lucky as to be ready to leave before I have to leave. If I leave late, the 100% will be eaten up more quickly by my more active driving, and I'll be stuck in more traffic, so more climate control means more energy use. I set this time every Sunday, calculated for the next weeks' worth of work, and every day that the next day is expected to be different.
Weekends:
  1. When I get home, I get it up to safe battery charge. I also try to make use of the solar panels, without going over. I set the target % and amps max both to work within these constraints.
  2. If the solar gets better, I readjust.
  3. In the evening, I set the amps back up to max. Sometime before the weekend (on Friday, or on the weekend itself), I set the time for charging to once again be during the good cost times (11PM-7AM). I target a safe battery level of around 60%, which in the 60D is the same as around 50%, which is a good spot to leave it long term.
  4. When I wake up the next morning, I determine when, and if, I will go anywhere. If I think I will, then I put the car to whatever % state of charge I want to charge it at, and tell it to start charging.
All the above are done from my room, hundreds of feet away from the car itself, except for changing the amps level. I don't have to unplug or plug in the car. I'm thinking of getting a charger with a pilot in it to make that work better remotely, too.
Wow. Owning a Tesla shouldn't be nearly this stressful. Not sure where your concern about "safe battery level" is coming from. Are you thinking of the recommendation to set charge at 50% for long term storage? If so, that's meant for storing the car for weeks to months, not overnight! Don't worry what your SOC is when you get home, if you're not needing to going back out that day and the car will charge overnight.

If you're running low on charge on your usual commute, then you chose too small of a battery. Unlocking it to a 75 would simplify your life and reduce your stress level immensely.
 
I would leave it plugged in especially for those that live in areas with winter climates. You can set scheduled charging for those with pricing tiers at various hours of the day + scheduled conditioning of the cabin + preheating battery pack + setting climate control prior to boarding, etc...

Also, there is a little bit of drain each day the car is not charged so the connected cable will keep it trickle charged to the desired battery level at all times. Want a bit more charge due to going on a trip? Charge from 80 to 100% about an hour before you plan on leaving through your mobile app; Lots more flexibility when the cable is connected--I do this by habit now whenever I park inside the garage.

NEMA socket wearing out...
Just this reason alone made me decide to purchase an extra UMC to just leave it plugged in.

** To me this car has been a life changer, really! But, dealing with battery maintenance and care is fairly simple and it should not take away from the quality of your life and ownership, but add to it instead. I thought about really watching to make sure the battery pack is stored and charged perfectly to ensure maximum durability in the years to come, but then it's more conscious effort and it takes away from what the EV was supposed to provide to me.. a large [huge] grin. Packs are supposed to last 8 years with decent performance and I believe it will be more just with proper and recommended care (and nothing more than that). I surely hope there will be a new or improved technology by then that will make our existing packs rather useless at that time. Maybe drop the pack and use it as a retrofit for a PowerWall auxiliary pack?
 
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Wow. Owning a Tesla shouldn't be nearly this stressful. Not sure where your concern about "safe battery level" is coming from. Are you thinking of the recommendation to set charge at 50% for long term storage? If so, that's meant for storing the car for weeks to months, not overnight! Don't worry what your SOC is when you get home, if you're not needing to going back out that day and the car will charge overnight.

If you're running low on charge on your usual commute, then you chose too small of a battery. Unlocking it to a 75 would simplify your life and reduce your stress level immensely.
Some people really like having fiddly, detailed, unnecessary routines. It's part of trying to do the best thing possible with items that are important to them. You and me? We'll just keep on plugging the car in when we get home and not thinking about it. Different strokes for different folks.