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Powerwall 2 Charge & Discharge Maximum Performance

Powerwall 2 Charge & Discharge Maximum Performance

I'm in the UK and have had a PW2 since May 2019. I've noticed that the maximum performance for charge and discharge seems to be 3.7kW as a maximum and then the grid import takes over. This aligns with PW1 set up and limits rather than the PW2 (continuous discharge is stated as 5kW maximum in the spec and 7kW instantaneous). Is this an installer configured option or enforced by Tesla? I think this may have been configured as a PW1 rather than 2. I've tried to contact support in the UK but this is proving problematical.

Passion2Fly | 10 December, 2019

why do you care? Tesla uses pretty sophisticated algorithms to protect the PW and enhance the lifespan. If the grid is up, why do you care about the PW's output power? If the grid is down, I've measured as much as 5.8kW output before the battery tripped... the problem is that the PW can only handle 5kW in backup mode, regardless of your solar output. this means that if you have a 7kW load and your solar is producing 5kW (let's say...), you cannot assume that this load will be ok (5kW solar + 5 kW PW). Your PW will still trip if you connect the 7kW load regardless of your additional solar output... I've just experienced that recently... and I'm not happy but I understand the complexity of managing active loads...

PapaSmurf | 15 December, 2019

I believe each Powerwall 2 is able to discharge at 5 kW continuously and peak at 7 kW for a few seconds to handle spikes. My at home testing has confirmed that to be mostly accurate so far.

I have two of the Powerwall 2 units. I have observed, when grid is cut (intentionally), that the batteries can easily handle around 9 to 10 kW of sustained output. It seems to be able to peak up to 14 kW, just as advertised.

I tripped the system into reboot when I turned on the electric heat system (no natural gas here). The house total consumption jumped to over 22 kW, which was more than the Solar system plus batteries could provide instantaneously.

Through testing, I have had the Solar (16.38 kW system) producing 10 kW and the batteries (at about 80%) providing 10 kW and powering the house consuming about 19 to 20 kW .... all while having the grid cutoff.

In my opinion, Tesla has designed the Powerwall 2 extremely well and it performs as advertised with the output levels. If you have at least two Powerwalls, that will provide continuous power at 10 kW, as advertised, in my brief experience so far.

Now in certain countries, they might have different software settings, with perhaps different maximums based on local regulations.