Powerwall 2 degradation

[sczsimos]

My Powerwall 2 was installed in about June 2020.

I am in NSW but the unit has not been connected to Tesla's grid service mode such as with @amberelectric.

Yesterday, I checked yesterday (using this method Discussion: How to get status information from your Powerwalls) on its current capacity.

If I am reading the data correctly, it has already decreased to on 11.15KWh (or about 82% of the original 13.5KWh).

I was quite surprised by the extent of the degradation, but I admit that I had suspected it because it seemed to be discharging much quicker than I recalled.

Anyway, at this rate, it looks like I am going to reach the 10yr/70% warranty in less than 4 years.

I am wondering what your experience has been?

Have I just got a defective unit ?

Should I be talking to Tesla now ?

Should I go through my original installer or go straight to Tesla?

 

[paulp]

My Powerwall 2 was installed in about June 2020.

I am in NSW but the unit has not been connected to Tesla's grid service mode such as with @amberelectric.

Yesterday, I checked yesterday (using this method Discussion: How to get status information from your Powerwalls) on its current capacity.

If I am reading the data correctly, it has already decreased to on 11.15KWh (or about 82% of the original 13.5KWh).

I was quite surprised by the extent of the degradation, but I admit that I had suspected it because it seemed to be discharging much quicker than I recalled.

Anyway, at this rate, it looks like I am going to reach the 10yr/70% warranty in less than 4 years.

I am wondering what your experience has been?

Have I just got a defective unit ?

Should I be talking to Tesla now ?

Should I go through my original installer or go straight to Tesla?

You havnt reached the warranty condition so presumably they will all tell you politely to go away until you do. The degredation may flatten as well.

 

[Nobody Famous]

Have I just got a defective unit ?

Seems to be within warranty specs for now. Check back later.

LFP FTW in home storage IMO.

 

[moa999]

If the batteries are like the car, most suffer a big loss in the first six months, and then it's far more gradual

 

[sczsimos]

If the batteries are like the car, most suffer a big loss in the first six months, and then it's far more gradual

Yes I'm aware of that.

But 18% in far less than 2 years is a lot when you've only got 30% to play with.

That's why I'm wondering what other PW2 owners are actually experiencing in order to compare.

 

[Nobody Famous]

Can you see what it's cycle history is?

Some degradation discussion here

Tesla Powerwall 2 review - Specs, performance & cost comparison — Clean Energy Reviews

In-depth review of the Tesla Powerwall 2, Powerwall Plus battery and unique Tesla solar inverter. With 13.5kWh storage capacity, instantaneous backup and off-grid capability, the Powerwall is one of the leading home batteries on the market. We examine how it works, the cost, warranty, performance an

www.cleanenergyreviews.info

 

[sczsimos]

If the batteries are like the car, most suffer a big loss in the first six months, and then it's far more gradual

Yeah its apparently not like the car on the basis of this thread.

Seems to be a pretty linear rate of decline: Powerwall 2 Available Energy After 2 Years

Seems that what I am experiencing is actually pretty common.

 

[sczsimos]

Can you see what it's cycle history is?

Some degradation discussion here

Tesla Powerwall 2 review - Specs, performance & cost comparison — Clean Energy Reviews

In-depth review of the Tesla Powerwall 2, Powerwall Plus battery and unique Tesla solar inverter. With 13.5kWh storage capacity, instantaneous backup and off-grid capability, the Powerwall is one of the leading home batteries on the market. We examine how it works, the cost, warranty, performance an

www.cleanenergyreviews.info

No it doesn't provide the cycle history or the total throughput.

 

[jamesgo]

So when I was 100% charged and did Energy - Get Battery Data (Get Site Live Status showed the same) and got:

total_pack_energy 14023

My Powerwall 2 was installed in 2017 so its got NMC (Nickel-Manganese-Cobalt) Lithium chemistry and made at Giga Nevada.

Interestingly I saw these two settings, which would be nice to know how to enable.

vehicle_charging_performance_view_enabled FALSE
vehicle_charging_solar_offset_view_enabled FALSE

 

[Nobody Famous]

Could be worse. You could've bought a Powerwall 1 and been in dispute for warranty.

Here's 3 D.E.D. units for sale

Free local classified ads

Find Miscellaneous Goods ads in Kogarah Bay 2217, NSW. Buy and sell almost anything on Gumtree classifieds.

www.gumtree.com.au

 

[moa999]

Could be worse. You could've bought a Powerwall 1 and been in dispute for warranty.

Do you know the story behind these?

 

[Nobody Famous]

story behind these

Sounded like it was murky waters between Tesla and SolarEdge as to liability for warranty. At least the Powerwall 2 is all-in-one so less cop-outs.

I still say I'd take good design over good warranty any day.

 

[Vostok]

If I am reading the data correctly, it has already decreased to on 11.15KWh (or about 82% of the original 13.5KWh).

Anyway, at this rate, it looks like I am going to reach the 10yr/70% warranty in less than 4 years.

Should I be talking to Tesla now ?

I would do nothing until the capacity is below 70%. If/when it goes below 70%, I would suggest you first contact your installer for a warranty claim.

FWIW, my PW2 is 32 months old and 'total_pack_energy' shows as 10306 or 78.1% of the initial rated usable power of 13.2 kWh. If it started at 100% and the decline is linear (which it isn’t), it would go below 70% early next year - so not even 4 years .

But I’m not het up about it. I will sit it out and make a warranty claim when it is eligible.

I’d be much more het up if that was capacity loss on my car…

 

[jamesgo]

I believe the reason why mine is still total_pack_energy 14023 after 3.5 years of daily use is I was told for the first few months the batteries were overspec'd.

 

[sczsimos]

I would do nothing until the capacity is below 70%. If/when it goes below 70%, I would suggest you first contact your installer for a warranty claim.

FWIW, my PW2 is 32 months old and 'total_pack_energy' shows as 10306 or 78.1% of the initial rated usable power of 13.2 kWh. If it started at 100% and the decline is linear (which it isn’t), it would go below 70% early next year - so not even 4 years .

But I’m not het up about it. I will sit it out and make a warranty claim when it is eligible.

I’d be much more het up if that was capacity loss on my car…

Well it seems that Tesla does have a massive exposure brewing on these units.

But I am a bit het because a unit with this much degradation is not as useful as one with the full depth of discharge on a hot summer or cold winter night. And that's what its for.

 

[paulp]

Sounded like it was murky waters between Tesla and SolarEdge as to liability for warranty. At least the Powerwall 2 is all-in-one so less cop-outs.

I still say I'd take good design over good warranty any day.

Under consumer law any warranty claim must occur through the retailer, and the retailer can not remoe their responsibilty to manage the claim with the manufacturer.

 

[Nobody Famous]

Under consumer law any warranty claim must occur through the retailer, and the retailer can not remoe their responsibilty to manage the claim with the manufacturer.

Seller is installer but having issues getting his money AFAIK. Purchaser got replacement.

 

[Stratman]

6 Weeks old and have "nominal_full_pack_energy" 28133. be interesting to see how they track over the years. This time of year using around 30% of capacity overnight

 

[jamesgo]

6 Weeks old and have "nominal_full_pack_energy" 28133. be interesting to see how they track over the years. This time of year using around 30% of capacity overnight

I assume you got two Powerwall units installed with that nominal size.

 

[Vostok]

Well it seems that Tesla does have a massive exposure brewing on these units.

It certainly does. Your and my experience is not at all unusual if the USA Powerwall threads are anything to go by.

But I am a bit het because a unit with this much degradation is not as useful as one with the full depth of discharge on a hot summer or cold winter night. And that's what its for.

Well, OK, but the bulk of the value in a Powerwall is in is first 10 kWh of capacity, not the last few. But YMMV.

This post shows the results of some "what if" modelling I did, based on my own solar generation and usage patterns. Click on the graph, it shows rapidly diminishing returns after 1 Powerwall.