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Tesla Announces Home Battery System

An anonymous reader writes: Early this morning, Elon Musk finally revealed Tesla's plans for the home: battery systems designed to store up to 10 kWh of power. The company is leveraging the battery technology they've developed for their electric cars to enable more people to switch to renewable power for their homes. There will be two models of the battery. The 10 kWh version will cost $3,500, and the 7 kWh version will cost $3,000. They can deliver power at a continuous rate of 2kW, with peaks up to 3 kW. Crucially, the batteries will be warrantied for 10 years. Musk thinks the market for home batteries will expand to at least two billion, eventually. But even a much smaller uptake for now will validate the creation of Tesla's "gigafactory."

"The gigafactory is the recipient of the largest incentive package ever given by Nevada at $1.3 billion, which followed a hotly contested tax incentive bidding war between various states to land the Tesla battery plant. For the investment to pay off, Tesla needs to convince hundreds of thousands of consumers per year to buy its cars and battery products, with the gigafactory serving as a cornerstone to the company's sales strategy. ... An early gigafactory rendering released by Tesla stated that the plant will have an annual battery pack output of 50 gigawatt hours — the bulk of which will go toward batteries for cars with most of the remainder to be allocated for stationary batteries, according to figures mentioned by Tesla's chief technology JB Straubel last year. The gigafactory's sheer scope makes other battery products a possibility as well."

46 of 514 comments (clear)

  1. Gamechanger by vakuona · · Score: 5, Insightful

    This battery could power a smaller sized home for a whole day. Kind of thing that can make solar energy viable.

    Love him or loather him, but Musk is changing the world.

    1. Re:Gamechanger by hodet · · Score: 5, Interesting

      I priced out a backup propane generator as a backup for my home that cost about the same thing. Never went with it. This could provide a home with good backup power in case of outage. (keep the sump pump or the furnace going anyway)

    2. Re:Gamechanger by ShanghaiBill · · Score: 5, Interesting

      Panel efficiency falls by half during cloudy weather, but you will still get some power.

      You get less power on cloudy days, but you also need less, since AC is the biggest consumer of residential power.

      Just means you pull more from the grid during winter.

      Which is not that much of a problem. Winter power consumption is spread out more than summer consumption, so the grid can deal with it more easily.

      The biggest challenge is the 5-7pm peak in demand. Just as solar is dropping off, people come home from work, kick on the AC to cool the house down, and turn on the appliances to start dinner. If these batteries can help shave off that peak, that will be a big help.

    3. Re:Gamechanger by Ol+Olsoc · · Score: 3, Interesting

      I priced out a backup propane generator as a backup for my home that cost about the same thing. Never went with it. This could provide a home with good backup power in case of outage. (keep the sump pump or the furnace going anyway)

      If nothing else, this should be +5'ed for informative.

      There is no free lunch. It cost me a good bit to provide backup power for my place, as you note, similar in cost to these batteries.

      And once in place, this system is much more convenient and takes much less attention than the traditional petrofueled mechanical generator system.

      Because it isn't only (ore even) about ROI. Its about providing a functional adjunct to the grid, which in my area is not as reliable as it once was.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    4. Re:Gamechanger by Anonymous Coward · · Score: 5, Funny

      It's a mixture between loathe and lather.

      You'll give him a bath, but you'll do it resentfully.

    5. Re:Gamechanger by LifesABeach · · Score: 4, Insightful

      One thing that Elon has done is causing me to evaluate his product and logistics compared to my usage.

    6. Re: Gamechanger by Anonymous Coward · · Score: 5, Funny

      The ac part really gets me. I grew up in a part of Australis where 40+ degree days (Celsius) in summer were pretty regular. And yet somehow we survived without any ac at all, just fans on really hot days.

      All it takes is decent insulation, a basic understanding of heat transfer (aka understanding why throwing open the windows and curtains when it's 45 outside and 30 inside "for the breeze" is a spectacularly stupid idea, but opening up all the windows later that night when the temp drops to the mid 20s is must) and not being a total wimp.

      So yeah, when is hear people talking about their desperate "need" for a/c it irritates me.

      Now git off the dried remnants of my lawn.

    7. Re:Gamechanger by Ol+Olsoc · · Score: 4, Interesting

      What would make solar energy viable

      2 thousand dollar houses would make homes a lot more viable too.

      I get your argument, I really do, but it's like saying that finishing the living room or kitchen isn't viable because of the cost. You could just staple plastic to the walls, and get cardboard bankers boxes from Staples instead of cabinets and save a lot of money over kitchen cabinets and drywalling.

      Reductio ad absurdum arguments aside, yes, solar and batteries technology is expensive, but it is falling. Coupled with reductions in power needs as we get more efficient lighting and appliances you'll see a lot of the arguments fall like dominos.

      If I might give an example. I concurrently re-insulated my house, and switched from an oil furnace to one of the new super-efficient gas furnaces, which burn so clean and efficiently that the chimney is a PVC pipe and a condensate return to the sewer.

      I now spend for the entire heating season roughly what others in houses my size and in my area are spending a month. If ROI is paramount, I've reached that point after a few years.

      That isn't even taking into account the increases in comfort, less housecleaning because of cleanliness (oil heat is filthy) and reduction of electricity use because the gas furnace blower fans are also engineered for efficiency.

      Finally, yeah, its expensive, but all these advancements are at first. Its started off as people for whom money isn't an object, but are interested in the gee whiz factor. Then as production economy starts to kick in, the costs start to come down, and more and more people start using it. Eventually it becomes the norm.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    8. Re:Gamechanger by Jeremi · · Score: 3, Informative

      What would make solar energy viable would be panels that didn't cost $30,000 to buy and install. [...] I just don't happen to have $30K laying around.

      This game changer has already occurred in many places. There are many locations where you can get a home solar array installed without paying any money for it, because the installing company is willing to pay for the equipment and installation in return for selling you the generated power. This is appealing to consumers because they get a significant reduction in their monthly power bill, they don't have to pay anything, and they don't have to take on the risk of not getting the expected return on their investment.

      The fact that solar companies are willing to take the financial risk on the customer's behalf indicates that the risk/reward ratio of home solar installations is already low enough to be economically viable, and it will only improve over time.

      --


      I don't care if it's 90,000 hectares. That lake was not my doing.
    9. Re:Gamechanger by wile_e_wonka · · Score: 5, Interesting

      Like the parent post said, "Musk is changing the world":
      Solar City lets you buy your solar panels for zero down and "lets you pay off your loan with monthly payments based on the electricity your system produces." So it ends up that the electric bill plus the Solar City bill add up to less than the old electric bill. You don't need a pile of money lying around to buy a modern home solar system. Non-wealthy people who do not care about the environment are signing up with Solar City simply because they'll pay less for utilities.

      So, yeah, Musk is changing the world--he's causing people who don't care about the environment to put solar panels on their house that a few years ago would have made zero financial sense. In case you haven't noticed, he also made an all electric vehicle drooled over by people who don't care about saving gas.

    10. Re:Gamechanger by CastrTroy · · Score: 4, Insightful

      I think that power companies should offer more incentives for people to have these in order to smooth out the electricity demand. Imagine if everybody had one. The grid wouldn't need as much capacity, and they would be able to use more renewables because the draw would be constant and people could store their own power. Many electricity companies are already charging higher rates during peak times. This is one way to get rid of the peaks. It's already a $0.05/KWh difference where I live. If the price of these gets low enough, it might make sense for everybody to install one, even without solar panels.

      --

      Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
    11. Re: Gamechanger by paulej72 · · Score: 5, Informative

      But what was the humidity level? 40C at 30%RH is much different than 40C 90%RH.

    12. Re:Gamechanger by I'm+not+god+any+more · · Score: 3, Interesting

      I think that power companies should offer more incentives for people to have these in order to smooth out the electricity demand.

      Why?

      Why is not the optimal consumer incentive which the electric company could offer the price difference between peak and non-peak rates? By "optimal" I mean socially efficient, not the biggest or whatever you happen to want the most.

      Here's why you'd want it in the UK. Apparently it's the only country in the world where consumers regularly cause 3 Gigawatt spikes:
      http://www.geek.com/news/tea-t...

      These folk are not going going to notice/care if you charge them double during the spike - because it's peanuts, a small fraction of a KWh. If you try and charge them 100X then they'll rebel and have you investigated for price gouging. So, no, pricing alone won't smooth out these demand spikes.

      If each house had a battery and a smart grid could tell each house when to use that battery, then it could smooth out those spikes very nicely.

    13. Re: Gamechanger by alispguru · · Score: 3, Insightful

      What is the average humidity on those 40/20 degree days?

      Come visit my home in the Washington DC suburbs, in. say, August. After a week of 90/90 weather (90+ degrees F, 90%+ humidity) you'll be crying for AC too.

      --

      To a Lisp hacker, XML is S-expressions in drag.
    14. Re:Gamechanger by Ol+Olsoc · · Score: 3, Insightful

      I'm willing to pay that much just to have the safety of backup power. This will happen within the next 5 years for me.

      Absolutely this is great news for people.

      But isn't it strange how on Slashdot, something as benign and wonderful as a backup power syste, that isn't Gasoline, diesel, or natgas powered is so widely condemned?

      It's like the site has been taken over by those old guys that spend all day down at the legion drinking beer, then go home to chase thos damn kids off their lawn. They don't know much except that whatever it is, they don't like it.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    15. Re:Gamechanger by MozeeToby · · Score: 4, Interesting

      $0.50. That's how much savings one full charge/discharge can save you at current rates. That's $182 per year. Even people that plan ahead balk at a 5 year payoff, so you'd have to have the cost for a 10kWh battery be under $1000 to get people to buy in. Even $2k seems unlikely at technology and market levels.

      Obviously those numbers change if the peak/off peak ratio changes, but $0.05 isn't enough of a difference to make it practical for that usage. Of course, it also functions as backup power or quite possibly can be used to increase the effective efficiency of renewables. I'm not trying to say that the system isn't impractical, just not economically sound for the on/off peak power shifting.

    16. Re:Gamechanger by mspohr · · Score: 4, Informative

      5 cents is low. Most time of use differentials are much higher. In my area, it is 14 cents. At that rate, it works out to $1.40 a day.
      This is $511 a year return on a $3500 investment... pretty good return.

      --
      I don't read your sig. Why are you reading mine?
    17. Re:Gamechanger by mspohr · · Score: 3, Informative

      You don't have to have a string inverter. You can use microinverters such as Enphase.
      Cost 250w panel=$200 plus 250w microinverter=$150 total $350. This is below the limit for requiring a building permit where I live ($500).
      Just add them one at a time.

      --
      I don't read your sig. Why are you reading mine?
    18. Re:Gamechanger by BlackPignouf · · Score: 4, Informative

      I'm working for a project in southern Germany where we do just that.
      The grid operator pays 50% of any battery installed. It's only for one small village right now, and we hope it will grow.

  2. Can't wait to get this installed in my house by talexb · · Score: 5, Informative

    Great idea. My power supplier currently has rates based on TOU (Time Of Use - http://www.torontohydro.com/si...), and I'd love to be able to charge up the battery supply for my house overnight at cheap rates, then run off the battery the rest of the time.

    I just hope it's not going to be one of those "Only available in the United States" deals.

    1. Re:Can't wait to get this installed in my house by ArcadeMan · · Score: 4, Insightful

      You didn't even read his post before replying.

    2. Re:Can't wait to get this installed in my house by duke_cheetah2003 · · Score: 5, Insightful

      Have you calculated the cost difference in hourly rates, your yearly use and the total price of such a setup? How long will it take to pay itself back before you see any financial gains?

      IMHO, this is totally the wrong way to look at this technology. Personally I don't care if it's more expensive than conventional power, if I could install a small wind turbine and a few solars on my property and charge this battery, it's off the grid for my acre. Totally worth it. People need to stop thinking in terms of 'its more expensive than conventional power.' That is the wrong way to look at this, IMHO.

    3. Re:Can't wait to get this installed in my house by RingDev · · Score: 5, Informative

      https://www.we-energies.com/re...

      Up to 17 cents cheaper per KWH (22c day, 5c night).

      Assuming you blow 10kWh per day, primarily between 6am and 11pm, that's upwards of $2.20/day.

      If you move your entire 10kWh load to the battery system and charge it over night, it drops you down to $0.50/day.

      $1.70 savings per day. That's 2058 days to recoup the $3500 expenditure, or just a bit over 5 1/2 years. Over the ten year warranty period you'll save ~$3000, assuming electricity prices remain constant.

      -Rick

      --
      "Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
    4. Re:Can't wait to get this installed in my house by Richard_at_work · · Score: 3, Insightful

      And if everyone does that, the cheap rate goes away - its only there because there is excess capacity at that time, and its not worth taking more generators off line during the middle of the night consumption troughs because it takes them time to come back up for the wake-up peaks. Thats the reason the cheap rate exists (we call it Economy 7 in the UK).

      So if everyone avails themselves of the cheap electricity in the middle of the night to store for use during the day, the excess capacity vanishes and instead we get an actual load needing to be catered for in additional capacity. So the cheap rate would be discontinued due to changes in consumption habits.

    5. Re:Can't wait to get this installed in my house by swb · · Score: 4, Insightful

      First, none of these things move forward without some enthusiast buy-in. Loads of things are stupid from a strict dollar-efficiency perspective but people still do them anyway. Computers held fairly low value in terms of dollar efficiency for decades, but enthusiasts found them worthwhile and helped move that industry forward.

      Second, you confuse cost and value. You know the cost of the utility power and the off-grid generation and storage components but you don't know the value to the consumer of being off-grid. What you see as a splurge they may see as some kind of inherent value.

    6. Re:Can't wait to get this installed in my house by AmiMoJo · · Score: 5, Informative

      Tesla give you a 10 year warranty and maintenance contract with the pack, so clearly these things are rated for more than 5.5 years of operation.

      Since the warranty is 10 years the MTBF must be significantly longer, to keep the failure rate low. It's interesting that the 10kWh pack is for "backup" while the 7kWh pack is for "daily cycling". I'd guess that the 7kWh pack is physically the same as the 10kWh one, only cycled 30% less to extend battery life.

      Realistically they would have to be looking at an average 20+ year lifespan to give you a 10 year warranty and maintain a profitable failure rate.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    7. Re:Can't wait to get this installed in my house by ledow · · Score: 3, Insightful

      However much you hate it, the bottom-line finance number gives you an idea of the materials, work, availability, etc. involved.

      A system that is not economically viable is taking MORE product out of the earth, and rarer products, that need more refinement and processing, etc. in order to create it in the first place than it is replacing other power-generation methods and their costs.

      It's quite simple. The market price changes to reflect the difficult, cost, legislation, rarity, etc. of the materials and labour involved. If something is more expensive it's because it COSTS MORE to give it to you. If something can't pay that cost back (at least, in a reasonable time) you've taken out MORE from the earth including shipping the thing to yourself and paying for machines to modify it, and paying for the companies mass-production plans, etc. than you've stopped being taken out elsewhere.

      It's not perfect. It's not entirely accurate. But the monetary cost of something is a pretty good indicator. This is why lithium batteries are more expensive than lead-acid equivalents, why oil products are being taxed, why discovery of shale gas can drop the gas price, etc.

      Also, as you're moving the burden from government and entire countries to individual users here, cost matters more than most other things. You're asking ME to take the effort, research, purchase, maybe pay for planning and electrical works, etc. this product that you're SELLING in order for me to help the earth. There's a cost involved in that no matter what. Some of that cost is a "donation" because you want to live in a friendly way. Some of that cost is because of the convenience to you if the power blips for a moment. Some of that cost is for your peace of mind.

      At the end of the day, cost is a pretty good measure of all kinds of things to do with a system. This is why energy companies are complaining about the "payback" electricity schemes from solar users... the costs they incur to put their pittance of electricity back into the grid far outweigh anything else. The government has to subsidise those costs, or the electricity companies have to raise their prices. And, suddenly, it's actually more expensive to run "off-grid" than you thought and you end up going back "on-grid" because the cost isn't worth the convenience any more.

      I could UPS all my appliances today. I could just buy a tiny UPS, or save up towards a bigger one, each month and stick them on batteries that survive power outages for whatever length of time I choose to do it for. But I don't because it costs. And that cost does not compare to the cost of the power going off every now and then, or the electricity company raising its prices by 10% a year.

      If an off-grid system does not return money for you, the money you pay would have been better off just buying a generator and some fuel for it for the rare occasions the power does go off, and forgetting about all these fancy gadgets that help you live off-grid. In which case, both the green-ness and the user suffer.

      That's why governments are subsidising PV etc. installs. They have to bring the price down or people will just look and think "Sod it, I'll just buy a genny and keep a tank of petrol in the garage for if anything happens" rather than go off-grid.

      Things have to be profitable, and everything has a cost.

    8. Re:Can't wait to get this installed in my house by ranton · · Score: 4, Insightful

      So if everyone avails themselves of the cheap electricity in the middle of the night to store for use during the day, the excess capacity vanishes and instead we get an actual load needing to be catered for in additional capacity. So the cheap rate would be discontinued due to changes in consumption habits.

      And when that happens the power companies would need far fewer power plants because peak usage would drop dramatically, perhaps around half what it would be otherwise. This sounds like a great situation.

      Temporary solutions to many problems is all we need as technology continuously improves. Take advantage of Time of Use rates today, and in five years switch to primarily solar power as the prices drop even further. Everything doesn't have to be a fix that will last a lifetime.

      --
      -- All that is necessary for the triumph of evil is that good men do nothing. -- Edmund Burke
    9. Re:Can't wait to get this installed in my house by Martin+Blank · · Score: 4, Insightful

      They will also offer an additional 10-year warranty that can be purchased at the end of the original for a comfortable 20-year warranty total.

      --
      You can never go home again... but I guess you can shop there.
    10. Re:Can't wait to get this installed in my house by duke_cheetah2003 · · Score: 3, Insightful

      Well said, also no one seems to be calculating in the environmental costs of conventional power, or the benefits to society as a whole when those environmental costs are reduced *IF* more and more of us switch over to such systems.

    11. Re:Can't wait to get this installed in my house by mspohr · · Score: 3, Informative

      Where I live, the time of use differential is 14 cents. I could save $1.40 a day with this battery. $511 a year for an investment of $3500... good return.

      --
      I don't read your sig. Why are you reading mine?
    12. Re:Can't wait to get this installed in my house by angel'o'sphere · · Score: 3, Informative

      No idea what you find rude.
      And no idea what you "believe" reasonable or unreasonable.

      There is no real loss involved in AC/DC conversion. Why should it?

      This one is 98% efficient:
      http://www.power-mag.com/pdf/f...

      This one 98.5%: https://www.google.de/url?sa=t...

      Sorry, your idea and the other /. ers that AC/DC conversion sucks up 25% is completely insane. There is no physical law thinkable of to cause such a loss.

      --
      Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
  3. unit mismatch by edittard · · Score: 5, Informative

    battery systems designed to store up to 10 kWh of power.

    kW is a unit of power. When you multiply it by a unit of time it becomes a unit of energy.

    --
    At the bottom of the /. main page it says 'Yesterday's News'. Well they got that right.
  4. 2kW with a peak to 3? by Anonymous Coward · · Score: 4, Funny

    So if you turn on your stove and clothes dryer, your TV shuts off? It's like my college apartment all over again.

    1. Re:2kW with a peak to 3? by Guspaz · · Score: 5, Informative

      No, you turn them all on at the same time and you draw the extra power from the grid. You're not going off the grid on a single 7 kWh battery pack. If you want to do that, they're stackable, up to nine of them.

  5. Prices May Vary by Toad-san · · Score: 3, Informative

    I'm reading the 10 kWh pack may be more like $4500 rather than $3500. I like that 10 year warranty though .. and you get whole-house surge protection of course, I'm sure.

  6. The utilities have reason to be upset by DaChesserCat · · Score: 5, Informative
    Many of the utility companies, such as the ones in Arizona and Hawaii, are griping about people adding solar PV to their homes. These people have, typically, used Net Metering; any power they produce in excess of what they consume at any moment is fed back into the grid and, when their demand exceeds their supply, they draw from the grid. The utility company gets to "reimburse" them for the power they contribute. In some areas (California), 1 kWh contributed during peak hours = > 1 kWh they can withdraw during off-peak hours. But that's pretty generous; most power companies don't even like 1 : 1.

    If you put enough PV on your home, you can eliminate your electric bill. At which point, many utilities argue, the costs of maintaining the grid (that's rolled into your electric bill, but not as a separate line item) are covered by the less-wealthy. The poor are subsidizing the grid for the wealthy, they argue. And they argue, further, that they should be able to charge people who are using Net Metering even if they ARE producing as much power as they're consuming.

    Where I live, I pay a monthly connection charge ( < $20 / month) + $0.085 / kWh. In short, my electrical co-op breaks these out as separate line items on the bill. Even if I put in enough PV to go Net Zero, so long as I'm connected to the grid, I'm at least paying the monthly connection charge. The Arizona utility wanted a connection charge / kWh installed PV, to the point that the homeowners who installed the PV ended up paying the same, without or without the PV. In short, they wanted to eliminate any incentive to add PV and connect to the grid. They did get approval for a connection charge / kWh installed, but it was a fraction of what they wanted.

    In Hawaii, where power is routinely $0.39 / kWh (it's made, largely, from imported petroleum), solar PV and Net Metering are so widespread that entire neighborhoods are producing excess power during the height of the day. It's to the point where HECO gets to veto whether or not you can add PV to your home; you have to get permits from them and they're getting harder to acquire. Because the transformers which convert distributed power (typically lower frequency and higher voltage) to the household power (60 Hz / 240 VAC split-phase) are made to work efficiently, one-way. Going the other way, they are considerably less efficient. If you are a net producer and your neighbor is a larger, net consumer, you're supplying your neighbor and the local transformer simply converts less power going into that neighborhood. When the entire neighborhood is a net producer, the transformer has a problem. So they limit how much power can be produced in each neighborhood.

    I used to think this was all about the power/utility companies trying to defend their bottom line. That's still part of it, but I've come to realize there are technical reasons, too. Installing efficient, bi-directional transformers would require:
    1. installing a second, bi-directional transformer
    2. taking down the power to an entire neighborhood while they switch over
    3. decommissioning and moving the old transformer

    at considerable expense. And that latter part, well, you KNOW they're not going to let their executives and/or shareholders eat that cost. And many utilities are regulated, such that they have to get approvals for rate increases. Which aren't easy to get. So there's technical reasons AND financial reasons for the utilities to grip.

    Put a battery pack on your home, like one of these. Get an inverter which feeds excess to the battery and NEVER exports to the grid. The power company loses their only technical reason to gripe, because you are no longer doing Net Metering. At that point, it's all about the Benjamins.

    Indeed, if you get to the point where your home is truly Net Zero, long-term, you can go completely off-grid. At which point they no longer have a say in the matter.

    --
    ... by the Dew of Mountains the thoughts acquire speed, the hands acquire shakes, the shakes become a warning
  7. Batteries by ledow · · Score: 4, Interesting

    It's about GBP30-40 for a 100Ah 12V car lead-acid battery on a random site. These are mass-produced, cheap and easily available. Granted that they are heavy and large, but... scaling up... that's 1.2KWh alone. We'd only need ten car batteries to match it. That's GBP300-400.

    Why, then does it cost the equivalent of nearly $3,500 (GBP2200) for the same here?

    Sure, we allow leeway for different voltages (necessary for high-current loads, etc.), different technologies, deep-cycle, etc. but... that's a five-to-seven-fold increase over what we're using now for quite basic solar, wind, etc. power storage and can be obtained from any garage. And 10 car batteries aren't prohibitively large, expensive, difficult to handle, etc.

    With 10 year warranty and 2KW peaks? That's way within range of such a pack. Hell, stick a decent split charger / inverter on the end, one designed for home use, and it still comes nowhere near the price of this home battery.

    Is my maths wrong? Have I missed something? Quite what are we trying to sell here apart from an overpriced battery and some electronics on either end of it?

    1. Re:Batteries by robosmurf · · Score: 4, Informative

      Lead-acid batteries typically last well under a thousand cycles, and also deteriorate if you deep cycle them. Thus you'd probably need to replace a car battery solution every couple of years.

      This isn't all that much better though. I don't think they have released the actual specs, but these batteries are likely to have a cycle life of around 3000 (which is consistent with the 10 year guarantee as they are unlikely to have a full cycle every day). This is much better than lead-acid, but as you say they are also much more expensive.

  8. Re:Another excuse for you to beat off to Elon Musk by Chas · · Score: 4, Insightful

    Steve Jobs merely made trinkets for douchebags with too much money.

    Musk, as self-aggrandizing as he may be, at least is genuinely trying to make the world a slightly better place (while making a buck at the same time).

    --


    Chas - The one, the only.
    THANK GOD!!!
  9. Its twice as expensive as the competition by Karmashock · · Score: 4, Informative

    I just did a price check and a 10kwh rolls royce deep cycle system with 4 of those batteries is about 1500 USD. Tesla wants 3000 to 3500. At that price, I could buy 20kwh to 30kwh in conventional lead acid batteries.

    The primary advantage of the Lithium batteries is that they're light. But in a static location what is the point of them? Who cares how much the batteries weigh if they never get moved? They sit in a utility closet somewhere in your house and that's it. I'm really confused as to why anyone would pay DOUBLE for Teslas batteries?

    Am I missing something? Why would I pay TWICE as much per kilowatt hour?

    What is more, deep cycle lead acid batteries can be reconditioned giving them a second life. I don't think you can do that with lithium batteries.

    Help me understand. This makes no sense to me.

    Here is a link to what I'm looking at as competition:
    http://www.wholesalesolar.com/...

    How are the tesla batteries better than that for this application?

    --
    I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
    1. Re:Its twice as expensive as the competition by Anonymous Coward · · Score: 5, Informative

      The Tesla system consist of:
          - 10kWh batteries
          - 3kW? battery charger
          - 2kW-3kW ac inverter
          - grid disconnect (for backup mode)
          - 3000? deep cycles
          - 10 year warranty

      and you compare it with:
          - 10 kWh batteries
          - 500 deep cycles
          - 3 year warranty

      and wonder why your system is cheaper? Really??

  10. 2kw could run 2x 600W ballasts by future+assassin · · Score: 4, Interesting

    to power 2 600W HID lights bulbs to grow weed off the grid. The battery would pay for itself in one crop of 8-10 weeks.

    --
    by TheSpoom (715771) Uncaring Linux user here. I have nothing to add to this but please continue. *munches popcorn*
  11. this is actually cool by sribe · · Score: 3, Informative

    On the prior article before the announcement, I posted about the economics not being that compelling, using my own actual numbers for consumption and peak vs off-peak pricing. I also noted that in some states, CA in particular, when peak pricing is ~60% higher than where I live, that it could start to be somewhat attractive.

    That was all based on the pre-announcement rumored price of $13,000 for 10KWh. At $3,500 for 10KWh, I'd be looking at a 4-year payback, or, in other words, about a 25%/year ROI. To be clear, that's without solar PV panels to generate electricity, that's strictly charging the battery during off-peak hours and then running the house on it during peak hours. (Quick calculation based on battery price alone; total installed system more likely to see 15%-20% ROI, but still, not bad.)

    I had wondered what Musk was up to and if the rumors were correct. Because you can already buy a 10KWh nickel-iron battery system for $13,000, so it did raise the question of what was the point? Well, now we know the point--1/4 the cost of existing competitive systems.

    One big question not answered by the linked article, is what technology is used and what's the depth of discharge without damaging the battery. With nickel-iron, you can discharge most of the charge safely. With lead-acid technologies, you can't go below about 70% without shortening the lifespan. So 10KWh can actually mean anything between 3KWh and 8KWh of usable power--a huge range. (Hey, maybe Tesla's going to be consumer-friendly here--maybe 10KWh means 10KWh of usable power... As this kind of thing becomes more common in the home, it would make sense to rate battery systems that way, to make direct comparisons easier...)

  12. This is good for green in more ways than one by davidwr · · Score: 3, Interesting

    If I'm a "wind/solar" or other non-24x7-generating company and I know what fraction of my customers have a several-hour-backup power supply, I can offer them lower rates in exchange for "turning them off" or even "buying electricity back from their batteries" in times of peak demand. This will let me offer services to more customers than I normally could handle.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
  13. Re:Disposal by jo_ham · · Score: 4, Informative

    You recycle them. They contain some lithium, a transition metal like cobalt or equivalent, and various anions (PF6, BF4, BPh4) that make up the electrolyte.

    You can separate out and recover all of the materials you used to make the battery and make another one.

    Lithium ion batteries also don't contain rare earth metals.