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Greetings all--I'm a newbie to the forum. I've got a few questions about charging at home to get the most bang for my buck and do what's best for the car--which is a 2021 Model Y LR. Here goes:

1. I do two types of driving: local, around town commuting and longer distance trips. Most (90%) of my driving is local. For trips, I set a scheduled departure time and charge fully overnight. That's the easy part.

2. For my normal driving, which usually consists of a few miles each day, I wait until the battery has about 60-75 miles left then I charge it overnight to 80% of capacity. Again, I use a scheduled departure time--which I usually leave at 0800 h--and charge overnight to take advantage of off-peak hour electrical rates. On an 80% charge, I can go up to two weeks before charging again, depending on season. Right now, in winter, my interval between charges is shorter. So my modus operandi is charge to 80%, take it down to 15% or so, then recharge. This is how I handle my normal commuting.

3. The question I have concerns whether I should plug the car in more often--perhaps even every night if need be. Of course, there is battery drain as the car just sits there--it's worse in winter. If I were to plug the car in after my daily driving is completed, would that mitigate the battery drain? I don't want the car to charge to 80% every time I plug it in, so if I turn off "scheduled departure" until I'm ready for a full charge, will plugging in the car just "keep things running" and prevent the battery drain? Is this technique healthier for the battery? One issue I have is plugging the car in during on-peak electrical hours--here from 5-9 PM everyday--which is much more expensive than off peak. When I do a full charge, the car doesn't start charging until off-peak hours, which is nice.

I guess that's it. I guess it boils down to a question of keeping my normal charging pattern or switching to plugging in all the time. Seems like plugging in every day is an unnecessary cost--but perhaps I'm missing something? Any advice from more experienced folks would be much appreciated. Cheers!
 
The greatest battery drain, while parked, comes from having Sentry Mode and Summon Standy (a FSD feature) active. Also, in warmer weather Cabin Overheat Protection remains active for 12 hours after you park. If you turn these features off (especially set Sentry Mode to permanently be off at your home location) the Tesla Model Y will enter sleep mode and use much less power than when awake, in standby mode. Don't keep opening the Tesla app as this will wake up the Tesla Model Y from sleep mode each time you open or launch the Tesla app.

Your charging method is not wrong but could be tweaked for better long term health of the battery.

I would only charge to 90% before a trip, not 100% and rely on the Supercharger network and tools such as A Better Route Planner to plan charging stops on the trip route.

You don't have to plug in every day but Tesla recommends that you keep the Tesla vehicle plugged in. A compromise would be to charge every other day or several times a week. You can set any daily charge limit from 50% up to 90%, whatever works for your needs. Some would choose 60% as the charge limit and try and maintain the battery between 40% and 60% (Personally I try to maintain the battery state of charge between 65% and 85% (in winter, a little lower in summer) but I only drive 12 miles per day (on average). The rest of the energy usage is from preconditioning using the Tesla app each time I drive.) My routine is predicable, currently using 8% to 10% of the battery per day. I currently charge 5X per week for 90 minutes at a public charger (~6kW charging rate.)

When plugged in, with an off-peak rate window entered, the Tesla Model Y will only charge during the off-peak time. The Tesla Model Y will charge the 12V battery (now the 12V is actually a 15V lithium module) as required using power from the high voltage battery via the accessory power system (APS.)
 
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It sounds like you have a garage with charging. So Tesla says leave the car plugged in if it’s an option so I always plug in when I get home, set the car to start charging at 11 pm to 70% (I only drive 15 miles a day), and forget about it. Don’t need to over think it.
 
Thanks all. I think I'll start plugging in every day or every other day, start charging at 10 PM--during my off peak hours--and only go to 70% or so. That way, I can always keep the car between 40-70% and it's plugged in more often. I'll check Sentry mode too. One quick question: say I'm done driving for the day at 5 PM and plug my car in (I have 230V in my garage). Say I set it to start charging at 10 PM to 70%. In the interim between 5 and 10 PM, is the connection to power doing anything? Or is it just sitting there waiting to charge? Thanks again.
 
Thanks all. I think I'll start plugging in every day or every other day, start charging at 10 PM--during my off peak hours--and only go to 70% or so. That way, I can always keep the car between 40-70% and it's plugged in more often. I'll check Sentry mode too. One quick question: say I'm done driving for the day at 5 PM and plug my car in (I have 230V in my garage). Say I set it to start charging at 10 PM to 70%. In the interim between 5 and 10 PM, is the connection to power doing anything? Or is it just sitting there waiting to charge? Thanks again.
Waiting to charge unless you initiate preconditioning via the Tesla app between the time you plug in and when charging would normally start. You can confirm the charging status by observing the light on the charge port. A blinking blue light indicates the following:

BLINKING BLUE: Model Y is communicating with the connector. Either Model Y is preparing to charge, or a charging session is scheduled to begin at a specified future time.

(Note: The charge port status light is not active if the Tesla Model Y is locked.)
 
Here in the Scottsdale area, our “Super off-peak“ rate is $0.03166/KWh - which is M-F between 10AM and 3PM. My car charges M-F up to 80% during that period and we skip charging all weekend. Today (Monday), when I plugged the Model Y in, we were at roughly 47% after light driving all weekend. Since our Model Y is new, I don’t know how low it will get if we do more driving, but I love to wring the best deal possible out of a situation.
 
If you want to baby the battery it's better just to reduce the charge level, rather than skip nights charging. Use 70% if you feel that 80% is too high (it isn't, really). That way you can feel free to use power hungry features like Sentry, and you won't get caught without enough battery if you have an unexpectedly long drive to make.
 
Ha! Guess what? I was under the mistaken impression that I do actually have on-peak and off-peak prices--but I just spoke to my power company (Pacific Power) and in fact I DON'T have different prices! Just one rate per kWh all day long, seven days a week. Damn! They do have an experimental program going on now that charges 0.24 per kWh from 5-9 PM and 0.06 per kWh at all other times. That's was at least one aspect of my question. Sorry for not having the complete information!
 
our “Super off-peak“ rate is $0.03166/KWh
OMG what a deal! No "off-peak" rates here but there is a $2 per kWh penalty to use power between 4 & 8pm. Regular rate is $0.1152 per kWh. More microwave dinners, with elaborate breakfasts and lunches, instead.

I concur with @davewill and charge more often, to 55%, more before a trip.