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The important missing control for Tesla Powerwalls

I’ve had Powerwalls for four years now. As my thread title suggests, from experience, Powerwalls lack one very important, if not essential control; the ability to fill it to a given capacity. I’m pretty sure I’m not alone in the view given that many owners use the popular cheap but short off-peak tariffs which we have in the U.K.
I‘m fortunate in as much as from late spring to late autumn , I have sufficient solar capacity to keep mine filled up. I know that in the depths of winter I will need to fill up most nights from the grid. In the these two scenarios they perform pretty much on the money. Others probably struggle throughout the year.

However, late autumn and early spring have always been a nightmare. I had hoped that major changes to the Tesla app which included adding tariffs and reducing the operating modes to just self-powered and time based control would resolve the problems. But it didn’t. I’ve just switched to time based control for the winter and I’m stuck in the same annoying rut that happens every year!

Recently we in the U.K. have had the usual dull wet days and bright sunny days. Apart from being unusually warm. Autumn has been what it always is and the daylight hours get shorter.

In Time based control, Powerwalls depend upon their AI to work out how much of their power came from solar, how much they discharged and how much they need from the grid. That works reasonably in stable weather conditions. It fails abysmally when a few sunny days are followed by a dull day or two and vice versa. Furthermore, the AI has no idea that even if there is some sun coming, I want my Powerwalls topped up from the grid because I’ll be charging two EV’s from solar tomorrow.

Here’s the annoying part; on two separate occasions last week there was little solar, the first night PW’s were at about 50% at bedtime and one car was empty. I set my reserve to 47% knowing full well that I would have to wake myself up before 2.30am to check what was happening. I did and sure enough, the car had charged but the Powerwalls had only topped up to 62%. I did what I always do and upped the reserve to 75% as I knew that the following day would roughly produce enough to finish the job, which it did. Two days later, same thing. Set a higher reserve at bedtime, get up in the middle of the night to up the reserve again to ensure that they are full enough for the day.

I won’t set a final reserve at bedtime because then I’ll be buying peak rate power and I shouldn’t need to. No matter how good the AI is, it will never be better than me because it can never have my overview of my needs. The answer is simple; an optional slider control to set a charge level exactly the same as my Model 3. Why on on earth was that ever omitted? Perhaps it’s a USA thing. It’s obvious to me and I would get a good night’s sleep!
Does anyone else want a charge control added?
 
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