Tesla in the home

[2lazy2retire]

http://www.bbc.com/news/technology-32545081

$3,500 seems a lot for what would be a days worth of backup?

[solon]

I think the main advantage of this is that it recharges when electricity is cheap, for later usage.

It will charge from solar panels during the day, so you can have electricity at night, or charge during off-peak hours, for use during peak hours.

Has anyone done the math? How long would it take to recover the cost of purchase?

[jmusic]

I think the main advantage of this is that it recharges when electricity is cheap, for later usage.

It will charge from solar panels during the day, so you can have electricity at night, or charge during off-peak hours, for use during peak hours.

Has anyone done the math? How long would it take to recover the cost of purchase?

Regarding covering the purchase price, I'm not sure it'd be easy to quantify a battery backup.  It could make sense for folks that have solar but no net metering available, or people that have really high peak rates. 

[GuitarStv]

I'm excited that there seems to be some push towards developing energy storage.  Solar power (and to some degree nuclear) is currently hamstrung by a lack of decent storage capability.

[rugorak]

I am curious on the math as well. For my apartment 10kwh would cover almost 2 days for me (at least for last month). I would be curious to see the average house's electric use. I did read that you could get more than one pack as well. So if you used more or really wanted to be without power for more than 1 day you could. Even if you just put these batteries in existing homes and keep them on the grid the flexibility would be huge. Normal power outages would be no big deal. You wouldn't even notice them. Plus the flexibility this would give home owners and utility companies should shake up the market quite a bit for the better.

[thd7t]

Does anyone think that Telsa will be the "luxury option" when it comes to home batteries?  I looked at the images and have to admit that I find them attractive.  However, attractive batteries will never be that important to me.  If they provide better storage, I am excited, but I wonder if there will be other companies who reach out as broadly as Tesla with more utilitarian versions.  I suspect that at $3k, you're paying some for product design as well as for engineering design and manufacturing.

[solon]

Even if you just put these batteries in existing homes and keep them on the grid the flexibility would be huge. Normal power outages would be no big deal. You wouldn't even notice them.

That's a great point. I didn't think of this. They could just start being standard in all new builds. Maybe even required by local electric codes.

[OldPro]

Not the same thing at all but related 2lazy is the following.

http://pureenergies.com/ca/free-solar-panels-program/

Not a scam at all, a genuine government backed program.  They install the solar panels on your roof at no charge and you get payments for 20 years for the electricity generated and sold onto the net.  If you then take that money and use it to pay all/part of your annual electric bill, you not only have contributed to green energy you have reduced your expenses as well.

I looked at it a couple of years ago as our house faces north which makes our back roof ideal.  My concern though was the affect on re-sale value of your home.  Unless someone is into it, I think a lot of home buyers would see the installation as ugly and undesireable.

[2lazy2retire]

Not the same thing at all but related 2lazy is the following.

http://pureenergies.com/ca/free-solar-panels-program/

Not a scam at all, a genuine government backed program.  They install the solar panels on your roof at no charge and you get payments for 20 years for the electricity generated and sold onto the net.  If you then take that money and use it to pay all/part of your annual electric bill, you not only have contributed to green energy you have reduced your expenses as well.

I looked at it a couple of years ago as our house faces north which makes our back roof ideal.  My concern though was the affect on re-sale value of your home.  Unless someone is into it, I think a lot of home buyers would see the installation as ugly and undesireable.

Interesting program - is there an option to have the company sustain the cost of removing them at the end of the 20 years if you no loner want them, or do the panels get upgraded during the lease term?.

[Guses]

I looked at the article but the information about the batteries is pretty scarce.

$3.5K  for 10 KWHr of storage is not bad at all if the batteries last a long time. Do they need maintenance?

I looked at converting to solar a few years back and could not justify it because of the (ongoing) cost of batteries.

I assume that these are deep discharge and that they can be drained completely without damage?

[backyardfeast]

Just a note that without solar, those of us in rural areas often spend 3500$ + on back-up diesel or gas generators (that mostly sit doing nothing until they are rarely needed for short amounts of time), so in that sense, I'm intrigued.  The batteries would be way quieter and less stinky!

[HipGnosis]

Does anyone think that Telsa will be the "luxury option" when it comes to home batteries?  I looked at the images and have to admit that I find them attractive.  However, attractive batteries will never be that important to me.  If they provide better storage, I am excited, but I wonder if there will be other companies who reach out as broadly as Tesla with more utilitarian versions.  I suspect that at $3k, you're paying some for product design as well as for engineering design and manufacturing.

Every new technology is 'expensive' because they have to recover their research and designing / engineering costs. Once the technology is proven and accepted, knock offs come to market at lower cost (though usually lower performance too).
An internet search of energy storage shows that it's anticipated to be quite big business as soon as someone brings a viable product to market.

[thd7t]

Does anyone think that Telsa will be the "luxury option" when it comes to home batteries?  I looked at the images and have to admit that I find them attractive.  However, attractive batteries will never be that important to me.  If they provide better storage, I am excited, but I wonder if there will be other companies who reach out as broadly as Tesla with more utilitarian versions.  I suspect that at $3k, you're paying some for product design as well as for engineering design and manufacturing.

Every new technology is 'expensive' because they have to recover their research and designing / engineering costs. Once the technology is proven and accepted, knock offs come to market at lower cost (though usually lower performance too).
An internet search of energy storage shows that it's anticipated to be quite big business as soon as someone brings a viable product to market.

I understand that, but I think the performance argument is a bit of a red herring.  Tesla is marketing this at a lower cost than existing Sony and Panasonic home battery systems, but they are clearly trying to make it something to be noticed (which doesn't impact performance).  In addition, as the market grows, it's easy to anticipate that additional research will lower costs and improve the technology further.  This is still an early generation consumer technology.

[v10viperbox]

I think the main advantage of this is that it recharges when electricity is cheap, for later usage.

It will charge from solar panels during the day, so you can have electricity at night, or charge during off-peak hours, for use during peak hours.

Has anyone done the math? How long would it take to recover the cost of purchase?

Depends on usage, I pay .11kwh after 6:00 at night because I have an electric car and they want you to charge at night. The biggest battery they sell is 10kwh. But the battery is 22kwh in total capacity so I would need a whole bunch of these to charge up the car from solar generated during the day. The Tesla battery is 4-5x the size of the one in my i3.

Figure you used the whole capacity every day charging at night for the reduced rate over the peak hour rate of .59 it would save you  4.80 $ a day if feeding form the grid to power it up for use during the day, 5.90$ if coming from solar.  So 593 days for payback not including installation or maintenance if you are using solar same if you bought two because you would still use it to charge the car or the house.

Now if I can feed solar into it and run my AC on sunny days for free and charge at night it might be a better proposition then doing solar and having to tie into the grid which is the expensive part. Panels are cheap, its installation and the grid hook up that kills you.  I would pay a fortune to run the AC during peak hours when it is hot, to cheap to do that though unless its 95+ out.

[powersuitrecall]

Even if you just put these batteries in existing homes and keep them on the grid the flexibility would be huge. Normal power outages would be no big deal. You wouldn't even notice them.

That's a great point. I didn't think of this. They could just start being standard in all new builds. Maybe even required by local electric codes.

Mass adoption of systems like this could be used to "smooth out the bumps" so to speak; eliminating the need for gas/coal fired generators to be fired up during the peaks.  That's pretty fantastic.

[Beaker]

Mass adoption of systems like this could be used to "smooth out the bumps" so to speak; eliminating the need for gas/coal fired generators to be fired up during the peaks.  That's pretty fantastic.

They're actually doing some utility scale installations for exactly that reason. More info on the Tesla page. That page also has some more info about expected duty levels and whatnot.

I've been wondering if electric utilities might subsidize these for people, along with a widget that lets them switch you to battery power when they want to. Similar concept to the "Saver Switch" they want to put on people's air conditioners.

[Prairie Stash]

I could go off grid with a solar system; currently I pay $30/month for the privilege of being connected. Right there its 10 years simple payback. I understand 10 years isn't great, it's worse on the panel side. Unfortunately the quote I received from a solar installer is still on the high side. I'm looking at $13,000 plus this battery if I go off grid. I would save around $1100/year so reasonably it would take 16 years for me. The installer said the solar panels alone would take 23 years, I wasn't enthused.

I wouldn't rush into it but it's a game changer with our relationships with the utilities. Imagine a newly constructed home; with solar and batteries installed. How much is the cost savings from not running power lines in? That's an offset to the system cost, is it worthwhile? Why do we need electric utilities to send us monthly bills?

[Travis]

Does anyone think that Telsa will be the "luxury option" when it comes to home batteries?  I looked at the images and have to admit that I find them attractive.  However, attractive batteries will never be that important to me.  If they provide better storage, I am excited, but I wonder if there will be other companies who reach out as broadly as Tesla with more utilitarian versions.  I suspect that at $3k, you're paying some for product design as well as for engineering design and manufacturing.

Every new technology is 'expensive' because they have to recover their research and designing / engineering costs. Once the technology is proven and accepted, knock offs come to market at lower cost (though usually lower performance too).
An internet search of energy storage shows that it's anticipated to be quite big business as soon as someone brings a viable product to market.

I understand that, but I think the performance argument is a bit of a red herring.  Tesla is marketing this at a lower cost than existing Sony and Panasonic home battery systems, but they are clearly trying to make it something to be noticed (which doesn't impact performance).  In addition, as the market grows, it's easy to anticipate that additional research will lower costs and improve the technology further.  This is still an early generation consumer technology.

It also seems to be part of Musk's M.O. to poke the big industries in the eye and show them they can do better whether it be Big Oil, Big Auto, the aerospace giants, and now in this case utilities and home construction.

[whydavid]

I live in the PHX area and the electricity provider in my area (Salt River Project) recently passed fees that they expect to average about $50 for new solar net-metering customers.

This technology could potentially allow solar customers to ditch the "net-metering" relationship and stay on a traditional price plan...booking huge savings as a result.  Another possibility is to use the battery system and a smart controller to smooth out peak demand from the home.  The $50 fee is actually a sliding scale based on your peak 30-minute usage during the billing cycle.  If the batter could be used to cut the top off of the peaks, you could save 20 or 30 bucks while continuing to take advantage of net metering.

This is really a potential game-changer here.  I'm grandfathered in under the old arrangement (the one that SRP claims is totally unfair...though they themselves proposed and adopted it for several years), but should I move or otherwise change circumstances this is definitely something I'd look into.

[rugorak]

http://money.cnn.com/2015/05/01/technology/tesla-home-battery-price/index.html

Some rough numbers at least.

I agree this is an early stage and Musk has pretty much said his goal is to shake the industry up. Especially with Tesla. I still think this is a great step in the right direction. Now if he can figure out a way to shake up the ISP industry I'll be all set. But unfortunately there are a lot more politics and local laws in the way there, and physics in the way with a satellite option :/

[dragoncar]

Not the same thing at all but related 2lazy is the following.

http://pureenergies.com/ca/free-solar-panels-program/

Not a scam at all, a genuine government backed program.  They install the solar panels on your roof at no charge and you get payments for 20 years for the electricity generated and sold onto the net.  If you then take that money and use it to pay all/part of your annual electric bill, you not only have contributed to green energy you have reduced your expenses as well.

I looked at it a couple of years ago as our house faces north which makes our back roof ideal.  My concern though was the affect on re-sale value of your home.  Unless someone is into it, I think a lot of home buyers would see the installation as ugly and undesireable.

I have a theory about that.  Right now, people with money are buying and installing solar panels because it has a good payback period.  But solar isn't just good for the individual, it's good for everybody.  There's really no reason for me to personally install solar on my partially shaded roof when my utility company can install solar in the nearby hills (same ones that have the wind turbines, perhaps) and pass any savings on to me.  Ultimately, everyone will reap the rewards of cheaper electricity regardless of whether they personally own panels.  And yes, they are ugly.  So in the future, I think solar panels on the house will definitely be a negative for resale/trendiness.

[Syonyk]

Being ugly hasn't hurt the Prius any...

[iamsoners]

I'm very skeptical of how power companies will respond to this.  There is clear potential that this could allow a significant portion of the population to move away from them as suppliers (and by significant I am saying even if 5% of people disconnect that has a huge impact on a highly regulated industry that has such heavy infrastructure requirements).

The trend in solar seems to be that energy companies are realizing that yes, it's more efficient for them to make solar farms and reap the associated tax benefits and lower production costs than to allow the customer to do it. And it seems like more and more they are pushing through regulations that make net-metering less appealing.

I am guessing the industry responds similarly by pushing through local level laws that require homes to be grid tied, or whatever other ingenius way they can think up to preserve the status-quo rather than looking at what's best for the consumer, eco-system, etc.

All to say, I don't forsee the utilities cooperating and taking advantage of the ability to create a more distributed power grid, smooth out their distribution, etc. even though those are good potential applications.  That said, I think enterprising smart MMM types will find the ways to use these batteries to significantly reduce cost and reliance on the traditional system--I just don't think the utility companies and their lobbyist are going to help us along.

[dragoncar]

Being ugly hasn't hurt the Prius any...

I don't personally think the Prius is ugly... however, there's a big difference between putting an ugly car in your garage and putting ugly panels on your roof.  Moreover, I'm not saying this will "hurt" panel manufacturers, just that it will move away from home systems and more to industrial systems.

[Syonyk]

Much like the Prius, solar panels are a marker of "conspicuous conservation."

People will want them there because it says something important about them.

And in general, at least so far, panels increase the value of a home by a few percent.

[big_slacker]

I saw the release and ran some quick numbers.

Our house in the PacNW (mild climate, no AC) spends 22 KwH/day average. Our electricity portion of the utilities bill is around $65.

The batteries come in 30 kWh/weekly cycle or 7 kWh/daily cycle.

An average $15k solar system here generates 3 kWh/day. 2 batteries would be $7k so $22k complete. Most energy is used in the evening. Without doing any field tests I'd guess the solar would charge the batteries enough to handle the evening usage. Maybe some small amount of grid would be used to keep the rest of the batteries topped off. Let's say this system might save us $50/month. That being the case it might take us 35+ years to pay off the system.

That's not to say energy costs might increase in the future and the cost of the solar + battery system is already locked. And there are probably fed + state tax incentives as well. But looking at it right now it's not such a great deal $$ wise. I'd wait for costs to decrease.

[forummm]

What are the benefits of the Tesla battery system over the lead acid batteries that are normally used for solar systems? Li-ion is obviously smaller and lighter and doesn't require maintenance. But I believe lead acid batteries are dramatically less expensive at this time. Perhaps they don't last as long, especially in hot climates? I think it's pretty common for car batteries (lead acid) to die after 3-5 years in hot places like Phoenix. But Li-ion can be sensitive to extreme heat too, depending on their electrolyte chemistry. Nissan claims their new Leaf batteries were baked for a year at 140 degrees night and day and didn't degrade much beyond normal usage would predict, so maybe Tesla has solved that as well. From their website it looks like the Tesla Powerwall does have the standard thermal control system that Tesla car batteries have too. Since they guarantee it for 10 years, I guess this could be cheaper than lead acid in the long run.

[MoneyCat]

I use net metering and pay less than $2.00/month in mandatory fees, so I don't really see the value in a home battery other than for power outages (which are infrequent).  I could see a home battery being more useful to someone with a $25.00 monthly utility fee.

[Thegoblinchief]

Nickel-iron batteries make a LOT more sense for home backup, and they last a long, long time.

[OldPro]

Not the same thing at all but related 2lazy is the following.

http://pureenergies.com/ca/free-solar-panels-program/

Not a scam at all, a genuine government backed program.  They install the solar panels on your roof at no charge and you get payments for 20 years for the electricity generated and sold onto the net.  If you then take that money and use it to pay all/part of your annual electric bill, you not only have contributed to green energy you have reduced your expenses as well.

I looked at it a couple of years ago as our house faces north which makes our back roof ideal.  My concern though was the affect on re-sale value of your home.  Unless someone is into it, I think a lot of home buyers would see the installation as ugly and undesireable.

Interesting program - is there an option to have the company sustain the cost of removing them at the end of the 20 years if you no loner want them, or do the panels get upgraded during the lease term?.

They allow for removing them once during the 20 year term to re-shingle the roof.  At the end of the 20 year period, you own the panels, they walk away and you are then free to sell your power to the grid directly.  I doubt they will remove the panels if you no longer want them on the roof though.  The key thing is they pay the upfront cost and maintain them throughout the 20 years.  You pay nothing for 20 years, just sit back and get cheques every year.  What you do at the end of the 20 years is up to you.

[Rob]

Does anyone think that Telsa will be the "luxury option" when it comes to home batteries?  I looked at the images and have to admit that I find them attractive.  However, attractive batteries will never be that important to me.  If they provide better storage, I am excited, but I wonder if there will be other companies who reach out as broadly as Tesla with more utilitarian versions.  I suspect that at $3k, you're paying some for product design as well as for engineering design and manufacturing.

Every new technology is 'expensive' because they have to recover their research and designing / engineering costs. Once the technology is proven and accepted, knock offs come to market at lower cost (though usually lower performance too).
An internet search of energy storage shows that it's anticipated to be quite big business as soon as someone brings a viable product to market.

I understand that, but I think the performance argument is a bit of a red herring.  Tesla is marketing this at a lower cost than existing Sony and Panasonic home battery systems, but they are clearly trying to make it something to be noticed (which doesn't impact performance).  In addition, as the market grows, it's easy to anticipate that additional research will lower costs and improve the technology further.  This is still an early generation consumer technology.

I can touch on this. Tesla Motors strategy has been to sell luxury vehicles that are able to outperform in their market through a number of technological improvements allowed with the electric powertrain in order to produce enough profits to move farther and farther into the mass-market through economies of scale, allowing them to accomplish their mission of accelerating the world’s transition to sustainable transport (www.teslamotors.com/about).

Tesla Energy is synergistic with that strategy because the economies of scale overlap, allowing Tesla to have the lowest cost of production in the market. Tesla is capturing those economies of scale through a giant battery factory called the Gigafactory (http://www.teslamotors.com/gigafactory). By 2020, the gigafactory will produce more lithium ion cells than all of the world’s combined output in 2013, at 50GWH per year. This is expected to decrease costs by a minimum of 30%. That's in addition to any improvements in battery technology which have been about 7% per year. So until another company commits to building a gigafactory, there will be no lower cost provider than Tesla. It just won't be possible.

Elon Musk wants to change the world through Tesla. It's not simply about profits for him. For more insight, you can watch the product reveal to get a sense of his vision with the Powerpack and Powerwall. https://www.youtube.com/watch?v=yKORsrlN-2k

Just another snippet from Tesla's about us page.
"Tesla is not just an automaker, but also a technology and design company with a focus on energy innovation."

[Albert]

Tesla will eventually have competitors in their market segment (be it cars or home batteries). It's not the type of market where one company can near monopolise market by being first or biggest (think Google or Microsoft).

[mohawkbrah]

What are the benefits of the Tesla battery system over the lead acid batteries that are normally used for solar systems? Li-ion is obviously smaller and lighter and doesn't require maintenance. But I believe lead acid batteries are dramatically less expensive at this time. Perhaps they don't last as long, especially in hot climates? I think it's pretty common for car batteries (lead acid) to die after 3-5 years in hot places like Phoenix. But Li-ion can be sensitive to extreme heat too, depending on their electrolyte chemistry. Nissan claims their new Leaf batteries were baked for a year at 140 degrees night and day and didn't degrade much beyond normal usage would predict, so maybe Tesla has solved that as well. From their website it looks like the Tesla Powerwall does have the standard thermal control system that Tesla car batteries have too. Since they guarantee it for 10 years, I guess this could be cheaper than lead acid in the long run.

this, i was just looking at lead acid batteries and they are 5x cheaper. some of them are described to have a lifespan of up 10-25 years. and they store just as much. this tesla battery is just a pretty and expensive version for the crowd that won't do there own research.

[Albert]

this, i was just looking at lead acid batteries and they are 5x cheaper. some of them are described to have a lifespan of up 10-25 years. and they store just as much.

If that is so how come they are not a lot more common for private homes? I've never heard of anyone have one of those. Or am I just badly informed?

[mohawkbrah]

this, i was just looking at lead acid batteries and they are 5x cheaper. some of them are described to have a lifespan of up 10-25 years. and they store just as much.

If that is so how come they are not a lot more common for private homes? I've never heard of anyone have one of those. Or am I just badly informed?

how many private off the grid homes do you know of?

don't be mistaken it's still cheaper and better off using power from a grid instead of trying to create a  self sufficient solar power array

I would like to try it though. i dream of living in the woods, hunting bee's having bear hives ect etc

[Syonyk]

What are the benefits of the Tesla battery system over the lead acid batteries that are normally used for solar systems? Li-ion is obviously smaller and lighter and doesn't require maintenance.

Smaller.  Lighter.  Less maintenance.  Can actually use the full capacity.  Lasts longer.  Less chance of acid spills.

Lead acid packs are actually quite miserable, they're just cheap and common.  They need regular watering, regular balancing charges (nobody bothers with a battery management system on them), and if you use a pack to anywhere near it's full capacity, you dramatically shorten the lifecycle of the cells.  Most packs aren't typically drawn below 50% unless something has gone really wrong, and if you want the pack to last a long time, you should generally be running closer to a 30% DoD (Depth of Discharge) - so you need ~3x more pack than you typically use, or your pack life will be measured in small single years.

You also have a substantial issue with https://en.wikipedia.org/wiki/Peukert's_law -  basically, the faster you drain a lead acid battery, the less you get out of it.  This is true of all cells, but it's particularly bad for lead acid, so you need a substantially oversized pack to be able to keep the C-rate (discharge as a ratio of the pack size) low enough that you're not losing massive amounts of energy to this.  Lithium chemistries are much more agreeable to higher rate discharges while still giving you most of what you put in.

The voltage sag on lithium chemistries is a lot less as well - they have a much shallower voltage drop as they discharge.  Lead acid sags a LOT on it's way down, so you have to handle this.  Or not, if you decide you care about battery life, and just don't drain the cells very far.

Right now, lead acid is still certainly a dominant chemistry for off grid, with nickel iron starting to catch up, but as the cost on lithium cells drops, they're a whole lot nicer to use.  That a lithium pack has come down to match lead acid in pricing is radically good - they've historically not even been close.  And for the same price, I'd absolutely rather run a lithium pack.

[obstinate]

I couldn't make the math work out. Under fairly optimistic assumptions, the payoff period is >10 years. Here's how I calculated it.

• Peak value of shifting a kWh of usage (summer difference between high and low tier energy price): 20c
• Number of kWh shifted per day: 7
• Number of summer days per year: 365 * .5

With my utility, the time-of-use difference in the winter is negligible, so the PowerWall would have no effect on my cost-of-use. Under these best-case assumptions, it takes about 14y to pay off. Here's my worksheet. Note that this assumes no solar panels. I'm making this assumption because apparently nobody wants to install solar on my shake roof.

Maybe for someone else things would be better. For example, if you have solar already, and you have watts in the morning that you can't use at all. But remember that if you're using your entire solar capacity, you can only count the difference between the power price in the morning and the power price when you end up using it. Also, things are less rosy if you have net metering.

All in all, I'm very hopeful for this idea, but I'll have to wait until the price comes down.

[obstinate]

Note that if you believe the system lifetime is twenty years AND you want to take my optimistic assumptions as reality, then it does make sense to buy one. Your savings over 20y are worth about $1000 in today's dollars. But I view that as a risky decision because almost no one is going to benefit as much as my assumptions suggest, and it's going to limit your ability to take advantage of future improvements in the tech, which will probably make it cheaper and more effective. There's also significant price/policy risk to your investment if power prices go down -- whereas someone who didn't buy the power wall can always do so later if prices go up.

Also note that my calculation assumes a 0% residual value of the PowerWall. If you think it will still have residual value at the end of twenty years or whatever your calculation horizon is, you'd need to adjust accordingly. Naturally that would make the scenario significantly more advantageous to the PowerWall.

[ender]

Just a note that without solar, those of us in rural areas often spend 3500$ + on back-up diesel or gas generators (that mostly sit doing nothing until they are rarely needed for short amounts of time), so in that sense, I'm intrigued.  The batteries would be way quieter and less stinky!

+1

This technology intrigues me. It will be a few years yet before I'm in a place to really benefit but it's really exciting to see someone pursuing this.

[dragoncar]

Much like the Prius, solar panels are a marker of "conspicuous conservation."

People will want them there because it says something important about them.

And in general, at least so far, panels increase the value of a home by a few percent.

Prius is a great example of my point.  Back when Prius first came out, it was a great market of conspicuous conservation.  But not anymore.  Rich people aren't buying Prius anymore, they are buying Tesla.  Likewise, I think wealthier homeowners with environmental agendas will just invest in a remote solar farm co-op, or buy unbundled renewable energy, and stick a "certified green home" sign on their lawn.

It's just my perspective, but I did grow up in well-off SF bay area communities, so I think I have a bit of insight into the way these "elite liberals" think.

[obstinate]

Much like the Prius, solar panels are a marker of "conspicuous conservation."

This is simply not true. In many places, you can have solar panels put on your house for no up-front cost, and no ongoing upkeep (except that you don't get 100% of the savings they generate). That may have been true ten years ago, but nowadays they make clear financial sense.

[forummm]

That a lithium pack has come down to match lead acid in pricing is radically good - they've historically not even been close.  And for the same price, I'd absolutely rather run a lithium pack.

So you're saying that Tesla's price is about the same as what a comparably performing lead acid system would be priced? A poster above seems to think lead acid is much cheaper. Perhaps they weren't accounting for the need to have twice the capacity of lead acid batteries to yield the same usable storage capacity?

[Syonyk]

Tesla has a 10kWh pack for $3500.

I can find 250AH 12v batteries for around $600 - that's 3kWh.

So, yes, you could get 10kWh of "nameplate capacity" for around $2k.  But if you actually use that, you'll destroy the batteries in no time (a few hundred cycles at *best*, and likely a lot less depending on the pack).

To get 10+ years out of that pack, you'll need 25-30kWh, minimum, "nameplate capacity" to get 10kWh usable.  Or to replace the entire pack several times.  Probably both. :)

So, yes, this looks cheaper than lead acid to me.  In addition to the zero maintenance aspects of it - no need to balance charge/water the packs/etc.

[forummm]

There's a consumer market for these. And it will grow. But it looks like the utility market is where the big opportunity is

http://climatecrocks.com/2015/04/16/why-battery-storage-is-already-unstoppable-and-will-be-huge/

[rocketpj]

We don't have natural gas to our house, so almost everything is electrical (though we heat with a pellet stove and only have the baseboard heaters as backup). 

We also have a tiered monthly electrical billing system.  So the first ~55Kwh are at a nice low rate, but then they go up dramatically from there.  We rarely get up to tier 2 in the summer, but winter is another issue.  However we also have less sun in the winter. 

I think I'll need to look into some local analysis of sun/solar/battery options.

[onecoolcat]

Does anyone think the state and federal governments will give tax credits or deductions for purchasing something like this?

[Chuck]

My electricity bill averages between 30-40 bucks a month, so this sort of thing will never be worth it for me financially.

[Syonyk]

Depending on the feed in rates you can get, it might be. If you can sell power when the cost is highest, this would be nifty.

Though the grid being utterly unsuited to distributed generation will make this a fun battle to watch going forward.

[ChrisLansing]

You can make a good battery bank out of golf cart batteries, but the system has that "back to the land/off the grid/free range tofu" look to it.   Plus it takes up a lot of space.   

If this power wall could be wired up to run only a few essentials -maybe the furnace, water heater, fridge, and a few main lights, then it might get you through 3 or 4 days of power outage.    That would make it a more sensible choice than a standby generator.     It's a bit pricey, but not really that bad, and the price will probably come down.   

My wife and I hope to have a very small retirement house in a semi-rural area.   We hope to have some solar panels.   We will definitely be considering the power wall at that time -about 8 more years.     

As an aside, the cynical part of me says that Elon Musk finally figured out that he can only sell so many electric cars at $57K +.    Better to get into something he can sell to a large percentage of homes nationwide.   

[jba302]

Based on our current usage and rates in MN, figured an 8ish year payback, full daily drain, with some hand-waving for the installation costs. With solar panels quicker but then the payback on the solar panels would be shifted. Sounds neat but it's not even remotely in my sights yet. 100% off grid, maybe, but then i'd be looking at something like a velkess flywheel for higher round trip efficiency and many more cycles.