Powerwall 2 vs Powerwall 3: Five Things That Changed

[@mikeb.7972]

Great video! I'm installing a Powerwall 3 and spent hours talking myself into Enphase and 5p batteries. I ended up going with the PW3 after all the research. Could have saved myself a lot of time just by watching this! Great job!! EE here.

[@ZachSolar]

Thank you very much! Great choice on going with PW3. Enphase makes a great product too. I think you would have been stoked either way.

[@nicejoy9998]

Can you add more solar to theses batteries as a DIY . Looks like the connection is simple. Any software program needed to add more solar ?

[@ZachSolar]

I’d imagine that it’d be pretty simple to do. Probably not “Tesla recommended”. Not sure of any negative implications. They do have their own installer app for system commissioning.

[@woohooivan]

11.5 kW out of one unit is impressive.

[@ZachSolar]

Absolutely is! It's wild to see how things have evolved.

[@James-rn7dv]

Good vid. Commenting for the algo. Cheers

[@ZachSolar]

Much appreciated, thanks!

[@AaronBregg]

Good video save for one part. You kind of tried to play down the safety issues with NMC batteries. Yes the chances of something puncturing the V2 case is low, it is still more of a safety concern that LiFePo. A small gripe for an overall great video. :)

[@ZachSolar]

Fair criticism! Battery chem is definitely not my wheelhouse. Thanks for watching 😀

[@krslavin]

There are still some losses in (PV) DC->DC (battery) conversion from high PV voltages to the battery voltage (using "buck" converters), but they are generally more efficient than via AC which also uses extra voltage conversions in addition to an inverter and rectification.

[@ZachSolar]

Definitely a good point!

[@tweeds638]

Best explanation of clipping I've seen so far! Thank you Zach! One question - if I buy a PW3 now and would like to expand my battery capacity in the future, how hard would it be for me to DIY add a DC expansion pack?

[@ZachSolar]

Thank you! Hmm, I wouldn't personally DIY anything with Tesla. I'm pretty sure they wouldn't allow the system to get commissioned if it wasn't installed by a certified installer. Labor on the DC-packs should be pretty affordable, especially if you can get your original installer to take care of you.

[@bladerunner1458]

Thank you for the simplified breakdown. we’re installing a ground mount system with bi facial collectors. Planning on having two powerwall 3, just curious if the inverter fails in one of the power walls will the other inverter and the other power wall take over. Would this be automatic or would have to do something to make it happen? do both inverters work in tandem so if one fails the other one just takes over. Capacity would be half as much

[@ZachSolar]

@@bladerunner1458 Assuming they were two powered PW3 units (not the DC-pack): If one inverter failed...then the panels strung to that PW3's inverter specifically would not work for you. The panels strung to the operable inverter would be working as normal. So you'd still have partial coverage, power, and capacity.

[@edc1569]

NMC is just a dumb chemistry for most home storage applications. Like all Tesla products the real difference here is their thermal management, that waste heat can go to keeping the pack in temperature range you want.

[@ZachSolar]

Good information on the thermal management. Thanks for sharing!

[@JBoy340a]

Great video. Can you mix and match a PW3 with a PW2 installation? We have a Solarroof and 2 PW2s and have been considering more battery capacity.

[@ZachSolar]

Thanks! As of now, you cannot mix and match PW2 and PW3. But I have heard that will change soon.

[@edc1569]

Are there any compatible optimisers for those that want them?

[@ZachSolar]

Tigo should be but I haven't confirmed with Tesla.

[@CorwinPatrick]

I was really hoping PW3 would be battery agnostic. Can you couple someone else's battery in place of the Battery-Only PW3?

[@ZachSolar]

If you want it to work well, unfortunately not. Tesla's system does not integrate with any other battery system. You could technically install a separate manufacturer's battery, but they wouldn't communicate together, work together, or back up the same loads.

[@thomasjacques5286]

My installer in St Louis is still saying the PW3 cannot be mated to my Enphase PV system with IQ8A micro inverters. I kept pushing back even canceling my order and they responded that that info came from Tesla. So I'm now back to getting two PW2 installed for

[@ZachSolar]

It’s 100% possible to do. We have already done it. The AC-coupling feature has been released for months now. It’s also confirmed on Tesla’s website, linked below. However, being under $16k for two Powerwall 2s is a good deal! I might opt for that tbh. Link: service.tesla.com/docs/Public/Energy/Powerwall/Powerwall-3-with-Backup-Switch-Installation-Manual-NA-EN/GUID-79918FB9-3068-4E1D-9599-A26D7AEAD331.html

[@edc1569]

Sounds like they still want to shift some pw2 stock. Guess if you can get a really great price go for pw2.

[@bitsorbytes]

Thanks for the recap. Out of interest, the PW3 can charge at 5kw, how about when an add on battery is added? Does this DC charge rate increase?

[@ZachSolar]

That's a good question. Yes, if it's a Powerwall 3 with the power components (inverter, etc). I’d assume not, if it's a DC-pack.

[@bitsorbytes]

@@ZachSolar So if you have a PW3 + DC Pack. What is the total rate you can charge from the solar? Still limited to 5kw like a single PW3 unit?

[@ZachSolar]

Let me confirm this with Tesla. I’m second guessing myself now on if the DC-pack would increase that input. I’ll let ya know.

[@bitsorbytes]

​@@ZachSolar Thank you! If you could check with Tesla that would be great. As it seems to be a bit of a bottle neck if the charging from Solar is limited to 5kw as you expand. Having a PW3 + 3 x DC-Packs is ~ 54kwh of storage, you're going to have a hard time to charge this from just solar @ 5kw during the winter months.

[@ZachSolar]

I confirmed that the DC-packs will not increase the 5 kW charge rate. The charge rate will only increase by adding more Powerwall 3s that have the power components. I agree with you, that 5 kW charge rate for the full 54 kWh would not be ideal. Good information to know!

[@gummiesrule88]

When do you think the DC expansion units will actually be available? There seems, as is somewhat common with Tesla, to have been some date slippage on availability of these units in particular. I heard fall of 2024 for awhile, then more recently "sometime in 2025...."

[@ZachSolar]

Tesla premier installers can order them now and they will ship out end of November.

[@gummiesrule88]

@@ZachSolar Thanks!

[@Hypertrev11]

Is it true that the Inverter and the Battery are linked in such a way that if the inverter fails you need a whole new unit? Or can the Inverter portion be swapped out? My concern is the batteries life span would be greater than that of the inverter.

[@ZachSolar]

This is correct. Inverter cannot be replaced separately. It’s because the housing is laser welded shut. The entire unit would need replaced. Not an issue when within warranty since you could get it swapped pretty easily. When you’re outside of warranty term, it could be more of an issue. However I’d hope there could be a better strategy to this in 10 years.

[@Hypertrev11]

@@ZachSolar Thanks for the reply! I've read that it is almost a certainty that the inverter would fail in about 10 years but the battery life span could be much longer. A shame to have to waste good batteries because the inverter has a shorter expected life span. Worst case scenario... Inverter dies just outside of 10 years. Best case scenario... Inverter dies just inside of 10 years and you get brand new batteries and inverter under warranty.

[@ZachSolar]

Subscribe for more! Thanks for watching :) If you need assistance with breaking down a solar quote, sizing your system properly, understanding your utility options, technical guidance, or just want another quote to review: Please email me at [e-mail]. Are you a solar professional looking for a new installation partner in Arizona, Texas, or Nevada? Shoot me an email at [e-mail].