Leaking PW 2s? #PowerwallRegrets

[catemma]

Should I have got a generator? Two PW2s installed end of November -- 2 backups total -- 1 during install for 5 mins, 1 in Dec for a few hours. FINALLY got charge up to 99% (never saw 100) -- says app. Why? Vermont-based - snow on panels from Nov-Apr. It was wonderful to see 99%. For a few days. Ever since discharging for some unknown reason. Now says 65%.
No answers from our installer (SunCommon). No answers from Telsa.
Also, due to snow, we can only realistically get 1 good use out of them during winter (assuming they actually retain their charge of course). The installer told us that they can recharge even with 6 inches of snow on the panels. No, that's bunk. Tested & doesn't work.
Is there a way to charge the PWs off the grid?
#PowerwallRegrets

 

[JohnRatsey]

I found that even having snow on part of the panels (it tends to slide down the panels when it melts but then stops on the roof which is rougher - see photo) massively reduces the solar output. It would need to be a special type of snow to pass significant solar energy through to the panel s. Were snow a regular feature where I live (it isn't) then I would be wondering about a heating system to get the snow to melt.

The technology exists for recharging the PW off the grid but whether it's enabled depends on location. I'm doing it in the UK (Cost-saving mode using cheaper off-peak electricity) and I recall that the Australians were doing it during theri winter. You have to persuade Tesla to enable the feature and this may well require permission from your electricity supplier.

 

[PBBear]

Is there a way to charge the PWs off the grid?

In Australia PWs are permitted to charge from grid - mine charges overnight from cheap off-peak grid power, if the predictive system thinks the next day's weather will be dim and there won't be sufficient sun to charge it up.
Its not a technical/capability issue, its a local regulation issue - speak to your installer and/or your local energy supplier as to what is permitted.

 

[nyprepper]

to the original poster, catemma..... you need to get the snow and ice off your panels. i'm struggling with it too. snow is easy. ice, not so much. PW's can't charge from the grid. so you need to clear up those panels. PW's have never hit 100% for me.... only 99% on the app. They will discharge 2% per day set in backup only mode. there is a rubber snow rake on amazon that is great for snow. but the ice is killing me..... see my thread below.

 

[Vines]

PW2 can charge from the grid, but only if configured that there's no solar. Its a local regulation issue, and so you should check with them to ensure you're in compliance with local laws.
Depending on your firmware version also they might not be able to charge and self heat. Self heating ensures that the battery is at operating temperature at any given moment, and when mounted outside the Powerwalls will consume more energy in the effort to keep themselves at temperature and ready for an outage. Earlier firmware versions did not allow both functions at once.

 

[Shygar]

Or if the powerwall is in Stormwatch mode it will charge from the grid in the US even if your primary source is solar.

For the snow, I searched google and found this:

A dozen tips for getting snow off solar panels

Only one that seems reasonable is the pulley/tarp system. But you would have to not forget.

 

[thegruf]

Snow on PV never really occured to me, why not heated wires in the top glass (as vehicle rear window) for colder climes.
Wouldn't need to melt all the snow as once the snow against the panel melts the rest will just slide off.
Sure it would consume a bit of the energy but used intermittently as required you would quickly be back to full operation.

 

[Shygar]

Snow on PV never really occured to me, why not heated wires in the top glass (as vehicle rear window) for colder climes.
Wouldn't need to melt all the snow as once the snow against the panel melts the rest will just slide off.
Sure it would consume a bit of the energy but used intermittently as required you would quickly be back to full operation.

I guess to me if you spend a bunch of energy to melt off the snow, then it's just a cloudy day, it would use more energy than you would gain. There's probably not a good way to do this unless you had an efficient way to heat up the glass in the panels.

 

[thegruf]

there is such a thing as weather data, would need much in the way of smarts to make it work.

 

[thegruf]

need ->not need