Tesla Powerwall $350 / kwh Retail

[nicobie]

If you have solar, in the future having one of these will be essential.

Right now I have net metering on my grid tie in. I am guaranteed it for 5 years, maybe more. My utility charges $.14/kWh for everything I use over my solar production. This is calculated on a monthly basis. If I generate more than I use. I get charged a $4.00 minimum usage fee. Once a year they do an accounting on my total use and production, then refund me only $.04 kWh for excess energy produced that year. I can see the minimum monthly fee doubling or tripling in the near future and net metering eliminated.

Without net metering (and state and fed rebates) going solar wouldn't make financial sense. In about 2-3 more years my system will be paid off so I will be able to buy one of Musk's batteries and do without any grid tie in if I have to.

I am going to buy a gen 2 Chevy Volt when they come out in a couple months. This will use up my excess power generation so maybe I am going to have to add one or two more panels. I might get away with what I have now. I hate having to pay that minimum monthly charge but won't mind paying a very small electric bill seeing as how I will be eliminating gasoline expenses.

BTW: the Volt will go about 5 miles per kWh. I will be driving <50 miles/day

 

[arkmundi]

That's cool. The idea of having solar power and an electric vehicle is my, and a growing number of people's, transportation modus-operandi. We passed an amendment to our Green Communities Act here in Massachusetts, that set the utility buy-back at retail. One more incentive on the stack of. Maybe this year I finally get solar on my roof. Condominium, so a bit of a higher bar than normal.

 

[arkmundi]

[youtube]yKORsrlN-2k[/youtube]
I loved this presentation, a lot! First, its my hero doing something remarkable, even given his already notable record of doing remarkable things. Second, he states his motive, that's its climate change and the sixth great mass extinction event under way. Not going for the "Darwinian Award." Third, that the solution, solar and battery, is not that hard to achieve, that a minuscule amount of solar and battery can replace ALL of the fossil-fuel generation in the United States, by its footprint. The "blue square" is the area of solar pv, the red pixel is the area of battery.

Fourth, I love that form factor. Its flat and relatively small for 10kw of battery power. Fifth - the cost - which will be $3500. And it has thermal management built in. I'm already thinking about how to build an 10kw LEV of some kind, combining that battery and the OSVehicle chassis.

Sixth - its available this summer and can be reserved right now, which I did, no money down:
http://www.teslamotors.com/powerwall
Seventh, and this is HUGH, he wants more gigawatt factories, not necessarily owned or installed by Tesla, so he has open-sourced the entire gigawatt factory, inviting anyone to replicate.

 

[silentflight]

I read the $3500 price was for installers, not retail.

Source? ? ?

As arkmundi said, you can go to the website yourself to put money down on one...

Only two years ago mainstream press were postulating that it would be difficult to get below $1000 / kWh. Even then it was possible, but a product like this on the market with some of the highest quality cells available embedded in a well engineered pack for $350 / kWh should generate some positive energy amongst ebike enthusiasts as it puts a stake in the ground on price and quality.

It's always fun to read the replies of guys who think a product introduced by Musk has no compelling aspects or can be readily bettered. He isn't perfect, but he is smart and is surrounded by young, smart, driven PhD's at all of his companies. SpaceX is accomplishing things that verge on the ridiculous, and that's just his afternoon job. I'm glad he's out there.

 

[Punx0r]

Fair enough, the BBC article I read must have been wrong. It's a pleasant surprise if these are on open sale to the public

 

[JackB]

And what prevents using a lead acid battery pack for this power storage, which is half the price
and has been available, I dunno, for about 100 years already. And is completely safe and simple,
and also HIGHLY RECYCLED. Has Elon announced his factory to recycle his batteries?

 

[arkmundi]

And what prevents using a lead acid battery pack for this power storage, which is half the price
and has been available, I dunno, for about 100 years already. And is completely safe and simple,
and also HIGHLY RECYCLED. Has Elon announced his factory to recycle his batteries?

Agree, see my earlier post http://endless-sphere.com/forums/viewtopic.php?f=14&t=69046#p1041674. But I'm captivated with the possibility of mobile-home light-weight solar and this battery provides a weight advantage.

 

[liveforphysics]

And what prevents using a lead acid battery pack for this power storage, which is half the price
and has been available, I dunno, for about 100 years already. And is completely safe and simple,
and also HIGHLY RECYCLED. Has Elon announced his factory to recycle his batteries?

Dedicated room to monitor and vent unsafe H2 levels. Acidic fumes that tend to destroy most things in the same room with them. Regular failures by design of a lead-acid cell, realistic shallow cycle capacity of 20-30% of name-plate. In exchange for all these absurd drawbacks and faults of lead-acid, you end up paying a premium over the clean compact and high efficiency Tesla battery.

The Tesla pack costs you less money up front, doesn't require sacrificing a room of your house to acid-fumes, and includes it's own DC/DC converter electronics to enable you to feed it the input from solar cells directly and have it manage itself and supply the voltage bus out directly to your AC inverter (or whatever thing you were wanting to power with it).

Lead's last hold-out function was stationary UPS supplies due to cost. Now with this pack having a lower system cost than lead, it seems the last useful function for lead-acid is boat anchors.

 

[okashira]

And what prevents using a lead acid battery pack for this power storage, which is half the price
and has been available, I dunno, for about 100 years already. And is completely safe and simple,
and also HIGHLY RECYCLED. Has Elon announced his factory to recycle his batteries?

Dedicated room to monitor and vent unsafe H2 levels. Acidic fumes that tend to destroy most things in the same room with them. Regular failures by design of a lead-acid cell, realistic shallow cycle capacity of 20-30% of name-plate. In exchange for all these absurd drawbacks and faults of lead-acid, you end up paying a premium over

The Tesla pack costs you less money up front, doesn't require sacrificing a room of your house to acid-fumes, and includes it's own DC/DC converter electronics to enable you to feed it the input from solar cells directly and have it manage itself and supply the voltage bus out directly to your AC inverter (or whatever thing you were wanting to power with it).

Yes, like I said, lead acid is for people who don't do the math. They appear cheaper, but if you actually look at full life cycle costs, NCA will be cheaper!
I am kinda surprised they have "liquid cooling," I guess so it can be mounted outdoors in the sun. If you mount it indoors, particularly with A/C, cooling is completely un-necessary.
I suppose they figured might as well because I'd bet they just have two Model S modules in them (reject cells for lower power?)

 

[arkmundi]

Lead's last hold-out function was stationary UPS supplies due to cost. Now with this pack having a lower system cost than lead, it seems the last useful function for lead-acid is boat anchors.

livelierphyic, you're a smart, moderately well informed respected member of the forum, but sometimes you pass into the zone of mere opinion as somehow factual, when its not and so must run the risk of presuming otherwise. Its why I gave you my source of information, the very well respected http://www.altestore.com/store/Deep-Cycle-Batteries/c434/, who sell all kinds of components, or complete systems, to accomplish an Alt-E conversion. If what you said were true, they would not have such a wide variety of lead-acid batteries. And why I recommended the modern sealed version, AGM or Gel or otherwise, because, well they're sealed and noxious fumes, etc, are not an issue.

But I do agree, this new Tesla PowerWall looks really, really good, dropping price so much, its hard to resist the lure. As I'm currently about to sign the dotted line for a solar-install, these questions are very much real for me, and not speculative. Best!

 

[speedmd]

If the pack requires liquid cooling, wondering how much domestic hot water can be produced as a by product.

 

[okashira]

If the pack requires liquid cooling, wondering how much domestic hot water can be produced as a by product.

None. The batteries in this unit will not produce appreciable heat.

 

[liveforphysics]

Lead's last hold-out function was stationary UPS supplies due to cost. Now with this pack having a lower system cost than lead, it seems the last useful function for lead-acid is boat anchors.

livelierphyic, you're a smart, moderately well informed respected member of the forum, but sometimes you pass into the zone of mere opinion as somehow factual, when its not and so must run the risk of presuming otherwise. Its why I gave you my source of information, the very well respected http://www.altestore.com/store/Deep-Cycle-Batteries/c434/, who sell all kinds of components, or complete systems, to accomplish an Alt-E conversion. If what you said were true, they would not have such a wide variety of lead-acid batteries. And why I recommended the modern sealed version, AGM or Gel or otherwise, because, well they're sealed and noxious fumes, etc, are not an issue.

But I do agree, this new Tesla PowerWall looks really, really good, dropping price so much, its hard to resist the lure. As I'm currently about to sign the dotted line for a solar-install, these questions are very much real for me, and not speculative. Best!

Learn about lead acid. Sealed ones are a joke for longevity.

The batteries on that page are garbage that deliver maybe 40% of the claimed name-plate specs when used in a real application, for a little while before failure. This is the nature of Lead acid.

Because someone is willing to write some numbers on a sticker and put it on a plastic rectangle filled with toxic garbage doesn't make the numbers on it real, doesn't make it a good idea to buy, and doesn't effect that this Tesla pack is a lower cost solution apples to apples.

 

[speedmd]

If the pack requires liquid cooling, wondering how much domestic hot water can be produced as a by product.

None. The batteries in this unit will not produce appreciable heat.

Liquid cooling is most likely a marketing move unless there are certain environments that it may be a bit better than passive radiant / convective solutions. Would think from a quick look to be more of a talking point.

 

[JackB]

Lead acid batteries have been used in RV and boats for decades, they have no real issue with all that nonsense.
In stationary applications, there is even less issues.
Musk wants to create low cost lithium batteries, that is great.
But this Powerwall is a stretch, and not a single bit of innovation involved, don't take a PhD to come up with this.
And with the very low discharge rate, isn't even all that useful to recharge an EV!

What I really want to know, can Tesla can RECYCLE their cells?
This really applies to all batteries when talking mass production.

 

[okashira]

Lead acid batteries have been used in RV and boats for decades, they have no real issue with all that nonsense.
In stationary applications, there is even less issues.
Musk wants to create low cost lithium batteries, that is great.
But this Powerwall is a stretch, and not a single bit of innovation involved, don't take a PhD to come up with this.
And with the very low discharge rate, isn't even all that useful to recharge an EV!

What I really want to know, can Tesla can RECYCLE their cells?
This really applies to all batteries when talking mass production.

NCA can provide 50x (5000%) more kilowatt hour transferred per pound of lead acid. Even with no recycling at all, my guess is they'd still win.

100 lbs of lithium ion batteries = 10.6kwh. 70% DOD for 4000 cycles. That's 42.7 MWh.
Lead acid would need 500 lbs for 70% DOD and 10.6kwh rated. But at 70% DOD you get what, 400 cycles. So multiply by 10.

100 lbs lithium ion (NCA) = 5000lbs lead acid. At this point transportation costs of 5000lbs of lead acid exceed disposal impact of lithium ion.

Oh, don't forget the Peukert's effect, self discharge, maintenance, float charging. Lead acid is like a black hole for electrons. A lithium ion based solar off grid setup would actually need a bit less solar power because of their higher efficiency.

 

[bikeelectric]

Does anyone know how the Tesla Powerwall would charge ? The specs say it is 350 to 400 volts. liveforphysics said something about it having a DC to DC converter in it but I have not seen any info on that. I would like to know if you could just connect up some solar panels to it - or if it is going to need some kind of charge controller . It would be great if all the BMS and controllers are built in but if not that could really add to the price.

 

[liveforphysics]

Does anyone know how the Tesla Powerwall would charge ? The specs say it is 350 to 400 volts. liveforphysics said something about it having a DC to DC converter in it but I have not seen any info on that. I would like to know if you could just connect up some solar panels to it - or if it is going to need some kind of charge controller . It would be great if all the BMS and controllers are built in but if not that could really add to the price.

It's DC-DC is ready to connect to a string of cells (or at least that's what Elon said in the video).

They also claimed 92% round-trip efficiency, which is quite impressive.

 

[JackB]

No question lithium batteries are better, although the cycle life claims are just that, claims,
I recall the early days claims of 5,000 cycles, what a big lie that was.

What maybe you don't understand is that we've had lead forever, its cheap, it works.
Having lithium does not suddenly change everything so we all need/want
to have some monster battery pack at our homes.
It solves a problem that doesn't really exists.
At least in the USA where our grid is VERY reliable.
TESLA create a market where there is none? Hubris from a Billionaire.

For EVs, that needs lithium or some other lightweight electrical storage.

And still want to know, can Tesla recycle these cells?

 

[liveforphysics]

What maybe you don't understand is that we've had lead forever, its cheap, it works.

I spent 5 years in the datacenter UPS industry at the MWh scale, with everything deployed in big installations being lead-acid. I can tell you if your definition of "it works" includes repeated random and regular cell failures, never delivering even 50% of the claims with respect to the ability to extract useful energy from them, constant vampire current needs to keep them charged (many 10's of kW 24-7 in big installations), complete replacement after every couple years, and destroying virtually anything they share a room with from acid fumes than yes, "it works."

The industry standard there is 2,000-4,000Ah 2V flooded lead-acid cells, which they pay an extra big premium for to be carefully screened and binned. You tediously measure specific gravity on the electrolyte of all the new cells before and after installation at full charge, you observe the float balance is perfect between the cells in the string, and that you're running them at exactly the mfg's specs for longest service life. You are running them in a temp and humidity controlled room, mounted in stationary racks with minimal vibration. Then, randomly a cell in the string dies of infant mortality (every other cell shows no issues). They pay another few hundred grand to replace everything with all brand new cells (because the cell mfg's don't recommend having different aged cells in a string together), in a year or two, one dies and you start over. Repeat this cycle indefinitely. AFAIK, that is still the current state of the art in lead for UPS backup as I know it from wasting years of my life dabbling in it.

I realize that during the times a lead acid battery isn't being replaced or maintained or cleaned or tested that it does work as a very disappointing and lossy battery that can make a big UPS system work, and that people have been putting up with them for so long that the industry is used to the exceptionally poor performance and keeps buying them. My hope is that this Tesla battery will end the cycle of making throw-away lead batteries that are just waiting to fail by design.

 

[speedmd]

Anyone that has had / dealt with a fleet of Lead acid battery EV's (fork trucks / golf carts) can tell you they suck badly. They are fine in your car when used to start it, but forget draining them down more than a few seconds at a time. They are terrible at charging and holding a charge long term. Would like to see the efficiency numbers in real life cycle terms for them. Would not at all be surprised if it were less than 50%.

 

[heathyoung]

Yep - can echo the sentiments about lead acid for UPS applications - having to replace one cell in a string is impossible, so you have to scrap 3 tons of lead to replace a single battery that's only 2 years old.

Enlightened UPS manufacturers are moving to lithium chemistries now anyway.

The only thing lead is good for is solder and for fishing sinkers.

I can see these being popular in Australia - power prices in some areas as high as 45c per Kwh, and a 0-6c feed in tarrif - real generous. The transitional FIT ends at the end of 2015 - might be time to look at this a bit more seriously.

 

[bronz]

Does anybody know about the difference between the 10 kWh and the 7 kWh versions? The larger one is said to be "optimized for weekly cycling" and the smaller one "optimized for daily cycling." What is it precisely that will prevent me from buying a 10 kWh and cycling it daily? If you want to have 30 kWh of storage, it is much cheaper to simply buy 3 of the 10 kWh than 4 or 5 of the 7 kWh.

 

[r3volved]

I think by cycle it means a single charge->drain cycle...
ie. Using the whole battery capacity in one day vs one week. (That's what I got out of it anyway)

Maybe different cell types? One with higher discharge and other with higher capacity?

 

[bikeelectric]

I have solar - I spent about $1000 for 4 6volt L16 lead acid batteries to make a 24v system a few years ago . They work, but I agree that lithium are a lot better.
If I take my L16 lead acid batteries as an example
manufacturers rating is

370 AH at C/20 rate
equals around 2Kw but as others have said you only get about half at best out of them if you want them to live long
so spending 7 times $1000 for lead acid to get worse performance than lithium . Does not make sense.
But with that being said -- when I can actually purchase the Powerwall for price listed and install it myself then I will believe it !