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Powerwall 2 and Integrated Solar

powerwall.tesla.com

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Re: Powerwall 2 and Integrated Solar

#121

Post by oasisbob »

Uptrenda wrote: post #119

You can buy 12v 250ah deep cycle AGM batteries from China for around $5 per battery -- lets assume another $15 for world-wide shipping. These kind of batteries would have around 3kwh of storage per battery but since you shouldn't discharge them to more than 50% lets also say that you need to double the number of batteries to achieve 14kwh of usable power for 28kwh of total capacity. At that capacity level, you would…

Source for that battery pricing? Seems WAY optimistic.

Given the weight + hazardous materials in an AGM, I can't see shipping hitting $15/unit unless you're talking about a container full.

Re: Powerwall 2 and Integrated Solar

#122

Post by beambot »

Uptrenda wrote: post #119

You can buy 12v 250ah deep cycle AGM batteries from China for around $5 per battery -- lets assume another $15 for world-wide shipping. These kind of batteries would have around 3kwh of storage per battery but since you shouldn't discharge them to more than 50% lets also say that you need to double the number of batteries to achieve 14kwh of usable power for 28kwh of total capacity. At that capacity level, you would…

Are you sure about those shipping costs to a residential address...? Professional installation? Process and guarantees from a reputable American OEM? Breakdowns and warranties?

I think you're missing a lot of costs beyond the raw materials...

Re: Powerwall 2 and Integrated Solar

#123

Post by nixarn »

andreyk wrote: post #116

His argument about the solar roof starts by equating the situation to how Tesla started out - electric cars were slow and ugly and needed to be sexy and cool to be attractive, and the same is true for solar. Except I highly doubt this is true here - do people really mind the look of typical roof-mount solar? My impression is that the upfront cost is just too high and cost recoup is just too slow. The argument for the…

Every time Elon presents something we have this coversation. I for one love listening to him talk compared to say the presenters at Apple and Microsofts recent event. He's genuine, doesn't feel like a salesman, talks about the reasoning and science behind it all in a great way.

Re: Powerwall 2 and Integrated Solar

#124

Post by Animats »

dangrossman wrote: post #115
rsync wrote: post #97

Earlier quoted context omitted.

"The thing is cloud-connected, remote-controlled by Tesla. " If your use-case is backup power in case of utility failure, how does that work ? If utilities fail, the network connection to the battery may also fail, right ?

Right, so you won't be able to use an app to monitor your Powerwall while it's offline... the battery's still going to work. Backup and off-grid are advertised use cases. Tesla's cars have the "cloud-connected, remote-controlled" stuff too, but they don't stop in the middle of the road if you leave cell phone coverage.

The nominal product life is 5,000 charge/discharge cycles, or 13-14 years if solar powered. Maintenance monitoring, including battery deterioration, is remote, from Tesla's end. Will that service still be running in 2030?

Re: Powerwall 2 and Integrated Solar

#125

Post by doikor »

Uptrenda wrote: post #119

You can buy 12v 250ah deep cycle AGM batteries from China for around $5 per battery -- lets assume another $15 for world-wide shipping. These kind of batteries would have around 3kwh of storage per battery but since you shouldn't discharge them to more than 50% lets also say that you need to double the number of batteries to achieve 14kwh of usable power for 28kwh of total capacity. At that capacity level, you would…

And once your self made cheap chinese battery pack ends up catching fire and taking your whole house with them you understand why you want to pay for some actual company to do this and have some quality control/insurance.

Re: Powerwall 2 and Integrated Solar

#126

Post by beefman »

Uptrenda wrote: post #119

You can buy 12v 250ah deep cycle AGM batteries from China for around $5 per battery -- lets assume another $15 for world-wide shipping. These kind of batteries would have around 3kwh of storage per battery but since you shouldn't discharge them to more than 50% lets also say that you need to double the number of batteries to achieve 14kwh of usable power for 28kwh of total capacity. At that capacity level, you would…

Where can I get a 250ah battery for $5? I see prices in the hundreds, and weights over 150 lbs.

Edit: Though we only need 5 of them, not 9. The whole point of deep cycle batteries is that it's OK to discharge the quoted capacity every cycle.

Re: Powerwall 2 and Integrated Solar

#127

Post by martin_bech »

manav wrote: post #75

I haven't looked into it yet, but I'm curious about using utilizing my Teslas in case of emergency for power. With 75kwh+ each (leased so no concern about cycles) I don't think I'd need a powerwall at home.

They would have more than enough power, but you cant pull power out of a Tesla. That would make supercharging to good of a deal.

Re: Powerwall 2 and Integrated Solar

#128

Post by davidivadavid »

nixarn wrote: post #123
andreyk wrote: post #116

His argument about the solar roof starts by equating the situation to how Tesla started out - electric cars were slow and ugly and needed to be sexy and cool to be attractive, and the same is true for solar. Except I highly doubt this is true here - do people really mind the look of typical roof-mount solar? My impression is that the upfront cost is just too high and cost recoup is just too slow. The argument for the…

Every time Elon presents something we have this coversation. I for one love listening to him talk compared to say the presenters at Apple and Microsofts recent event. He's genuine, doesn't feel like a salesman, talks about the reasoning and science behind it all in a great way.

The content of his presentation is always interesting. The delivery is always incredibly awkward and cringy.

Re: Powerwall 2 and Integrated Solar

#129

Post by Uptrenda »

Uptrenda wrote: post #119

You can buy 12v 250ah deep cycle AGM batteries from China for around $5 per battery -- lets assume another $15 for world-wide shipping. These kind of batteries would have around 3kwh of storage per battery but since you shouldn't discharge them to more than 50% lets also say that you need to double the number of batteries to achieve 14kwh of usable power for 28kwh of total capacity. At that capacity level, you would…

You guys do realize that most of the technology you buy is already made in China so its not like buying "American" is going to be some magical guarantee of quality. You'll find that a lot of the tech companies already have their products manufactured entirely overseas where the price is then marked up several hundred percent and sold to western consumers.

Regarding costs: I didn't factor in every possible cost but I still find it hard to believe that these high powered lithium batteries will work out to be cheaper than AGM batteries at this stage -- even factoring in things like shipping and installation costs (though I may be wrong about this, I think that this battery is likely to be like the Apple of PC components.)

By the way: If anyone is interested in suppliers have a look at companies like Guangzhou Henda Power Ltd and Guangzhou ESG New Energy Technology Co. They sell cheap AGM batteries like the ones I've mentioned. And you may even bump into one of SolarCity's suppliers if you do enough research ;)

Anyway, thanks for the downvotes for not band wagoning but none of you have any clue what you're doing.

Re: Powerwall 2 and Integrated Solar

#130

Post by TheSpiceIsLife »

intrasight wrote: post #88
TheSpiceIsLife wrote: post #58

Earlier quoted context omitted.

Where are you seeing $3000? When I set it to 1 Powerwall it tells me: One 14 kWh Powerwall battery $5,500 Installation and supporting hardware starts at $1,000 Total estimate $6,500 Requires $500 deposit for each Powerwall

I don't see $3000 - that's my point. But for $3000 I'd buy one.

Ah, right, I follow you now, thanks.
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