Tesla Powerwall 2

[Mike90250]

Hey Charlie: I'm not nuts about acronyms either, but: 1.) Someone was providing information for free. 2.) They are not your servant. 3 .) You have a brain. Use it. A quick Google check would have quickly zeroed in on the meaning as bberry demonstrated. Some things you will need to do for yourself.

Reminds me of the book "Everybody gets a Trophy"

[cebury]

Hey Charlie: I'm not nuts about acronyms either, but: 1.) Someone was providing information for free. 2.) They are not your servant. 3 .) You have a brain. Use it. A quick Google check would have quickly zeroed in on the meaning as bberry demonstrated. Some things you will need to do for yourself.

Off topic, but last comment remind me of something, though the commit is not the same.
I grew up in a small town in central CA that was 85% Hispanic. During high school, I worked retail at the local pharmacy and pizza place, and customers would get very pissed if someone didn't speak Spanish. One time a person yelled, in Spanish, "why are you speaking English, everyone here should speak Spanish". Goes along with the "I don't speak xxx, you must speak what I speak."

[J.P.M.]

I don't speak Acronym, so you will need to define your terms. As for the inverter, well, I didn't include sales tax, which is 7% where we're heading. In any case, even 11 cents/kWh for storage would be out of the question for generator replacement.

Hey Charlie: I'm not nuts about acronyms either, but: 1.) Someone was providing information for free. 2.) They are not your servant. 3 .) You have a brain. Use it. A quick Google check would have quickly zeroed in on the meaning as bberry demonstrated. Some things you will need to do for yourself.

[bberry]

I don't speak Acronym, so you will need to define your terms. As for the inverter, well, I didn't include sales tax, which is 7% where we're heading. In any case, even 11 cents/kWh for storage would be out of the question for generator replacement.

http://www.seia.org/research-resources/solar-investment-tax-credit-itc-101

[Charlie W]

In the U.S., the ITC applies to the powerwall when calculating cost per watt. You also need to account for the solar inverter that is included.

I don't speak Acronym, so you will need to define your terms. As for the inverter, well, I didn't include sales tax, which is 7% where we're heading. In any case, even 11 cents/kWh for storage would be out of the question for generator replacement.

[bberry]

In the U.S., the ITC applies to the powerwall when calculating cost per watt. You also need to account for the solar inverter that is included.

[Charlie W]

Tesla's page quotes a 10 year warranty and a 100% depth of discharge. (Presumably it has some unadvertised reserve capacity.)
If that's true, the price per stored kWh is 11 cents... which may put it in the range of practicality in areas with really high retail power prices (like Maui).

I saw the 100% number, and for purposes of argument I will accept it in spite of my skepticism. A lithium-ion battery has a 2,000 cycle working life. That works out to 20 to 21 cents per kWh stored. We don't have the text of the10-year warranty; my guess is that it's geared to the battery's intended use for TOU gaming, which would not entail daily use because of the structure of TOU pricing that typically excludes weekends. I'd also note that this type of use might not involve a full charge/discharge cycle.

Thus, absent more specific information, I stick with the higher numbers. It would most certainly not work for whole-house generator-style backup. Yes, because of the 100% depth of discharge claim, I'd need to make some downward adjustment in my initial cost estimates, but those adjustments aren't even remotely material for the purpose I have, and I don't think for TOU gaming either.

p.s.: My guess is that the battery indeed has a reserve. Lithium batteries do not like full discharges.

[J.P.M.]

Tesla's page quotes a 10 year warranty and a 100% depth of discharge. (Presumably it has some unadvertised reserve capacity.)
If that's true, the price per stored kWh is 11 cents... which may put it in the range of practicality in areas with really high retail power prices (like Maui).

OK Dan, if you think the LCOE is $0.11/kW, that's also below your POCO cost, so I expect you'll be among the first to do public service and put your money where your mouth is when/if this product becomes available ?

[DanKegel]

Tesla's page quotes a 10 year warranty and a 100% depth of discharge. (Presumably it has some unadvertised reserve capacity.)
If that's true, the price per stored kWh is 11 cents... which may put it in the range of practicality in areas with really high retail power prices (like Maui).

[Charlie W]

No question that Tesla knows how to package and sell inverters and lithium batteries. But a $5,500 solution that will cost 25 cents per kWh stored over its service lifetime simply does not make financial sense in any application I can think of. And most definitely not, not, NOT for the sort of off-grid and/or whole-house generator replacement that I need. Nor does it make sense for gaming a utility's TOU billing. I see no possibility that someone who time-shifted by using the Powerwall product could ever hope to pay back the cost of the batteries needed to do this.

[Charlie W]

I see some forum members still are having a problem with change.

I'm in favor of what works, at a competitive price. Period. The problem with Tesla-related conversations just about anywhere on the Internet is that they wind up being battles among stock speculators, both long and short. I'm retired from that world, but am highly familiar with it. My comments on the Powerwall product are 100% product related; I have no speculative interest in Tesla or its competition. How about you, "bbery?"

[gmanInPA]

Hmmmm... what is the latest version of the Samsung Galaxy - you know... the one that you can't fly with on airlines because it blows up, catches fire, etc? Certainly making a second version of something makes someone an expert! Please explain precisely how the Powerwall is compares to the alternatives and is superior to them. I'm very interested to know since I can't even get such information from Tesla.

[bberry]

It is a big world with many needs. The important attributes of a new product is how its features and cost compare to alternatives. This is a version 2 product from a company that obviously knows how to make battery packs and inverters.

[gmanInPA]

I see some forum members still are having a problem with change.

That is hardly a fair statement toward anyone on this forum who has implemented solar - something already quite uncommon in our culture and that already requires embracing change.

Blind brand loyalty without specific knowledge is silly. I really hope the Powerwall 2 does become something great. Two times I've tried to get them to come talk to me about installing. I've always been on their early adopter list. I'm hardly anti-change because I don't blindly accept Elon Musk's dog and pony show. I've worked for enough public companies to recognize the difference between real-life innovation and shareholder candy. I am sure that some will find some usefulness from them - should they ever materialize.... but are the revolutionary? I don't believe so. It's a battery - with a nice enclosure and perhaps some extra bells and whistles - whoop-de-do.

I would agree with Mike90250 that they have minimal load-shaving usefulness - not unless in large quantities and therefore huge expense.

In my opinion, the most benefit of load shaving is found if you have TOU rates that are crazy or all your loads are handled by your inverter. I don't have TOU rates, but if I did, it might be more appealing to use it more often. I like that I can if I want with about 5 minutes of work. I have found that when I've tried it, I'm just using the highest-premium energy (batteries) rather than the most affordable energy (POCO). Better to just turn off the main power for a day and make it worthwhile! Additionally, a battery has a finite amount of discharge cycles, so you're counting down from those every time your discharge the battery - even fractionally - for load shaving. If one doesn't mind doing so at a premium over POCO cost, have at it.

[J.P.M.]

I see some forum members still are having a problem with change.

But apparently not as much of a problem with reality than some others who see what they want to see and hear what to hear with little regard for objective, verifiable facts, reality and common sense.