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Power

"Home Batteries" Power Houses For a Week 325

tjansen writes "Panasonic has announced plans to create 'home batteries.' They are lithium-ion batteries large enough to power a house for a week, making energy sources such as solar and wind power more feasible. Also, you can buy energy when it is cheapest, and don't need to worry about power outages anymore."
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"Home Batteries" Power Houses For a Week

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  • Boom. (Score:4, Insightful)

    by ScrewMaster ( 602015 ) * on Thursday December 24, 2009 @11:05AM (#30544480)
    I don't trust lithium-ion technology enough to want something with that much capacity in my basement. Wouldn't want my house to look like this [tmcnet.com]

    I have a thousand watt-hour battery that runs my sump pum during a power failure, but it's lead-acid. They've been around for a loooong time and are pretty damn stable (even so, this one is in a concrete-walled sump room.) Lithium-ions have a ways to go before they can be considered as trustworthy, and their higher energy density just makes them that much more dangerous during a catastrophic failure. Yet another reason why I'd never buy a hybrid vehicle. The idea of sitting atop a massive lithium-ion battery pack makes me far more nervous than I've ever been about a tank of gasoline.
    • Re:Boom. (Score:5, Informative)

      by dunkelfalke ( 91624 ) on Thursday December 24, 2009 @11:12AM (#30544552)

      Dude, most hybrids out there use NiMH batteries. Sorry to give you cognitive dissonance.

      • Dude, most hybrids out there use NiMH batteries. Sorry to give you cognitive dissonance.

        And why would that be? Hybrid makers would like to use the lightest, most energy-dense batteries they can to increase range, and if they're not using lithium-ions I'm sure there's a pretty good reason. Stability is probably one of them. In any event, if you crush a large battery (say, in an accident) what do you think is going to happen, regardless of the chemical system?

        • Re: (Score:3, Insightful)

          by dunkelfalke ( 91624 )

          I used to work in the automotive industry and I can answer you that. Car manufacturers and their suppliers never use the newest technologies. It takes years to switch technologies, both because older technologies are tested and approved and because of financial reasons (tools for older tech have to be paid off).

        • Re: (Score:2, Interesting)

          by ircmaxell ( 1117387 )
          Forget crush (It's not that difficult to armor the batteries)... What happens when you short one out? I remember seeing a video of a firefighter cutting someone out of a hybrid. They went to cut the seat supports, and accidentally cut the 400v DC positive line that was running under the center console (It runs in a tunnel from the trunk up to the engine compartment)... It instantly welded the cutting tool to the ground, and proceeded to destroy (rather catastrophically) the batteries. The firefighter s
          • Re:Boom. (Score:4, Interesting)

            by Zerth ( 26112 ) on Thursday December 24, 2009 @11:55AM (#30544972)

            I remember another video where a firefighter was holding C-Spine traction (Holding the victims head still, to prevent spinal injuries from causing more damage) on a 2 seat BMW. One that had explosive actuated rollbars that came up only in the event of an accident (I assume to maintain the aesthetics of the car). Well, while they were freeing the victim from the wreckage, the rollbars were somehow triggered. When it came up, it hit him in the neck right below his jaw and killed him on the spot.

            [citation needed] /morbid curiosity

            • I couldn't find anything on it quickly before I head home from work. I'll look around when I get home. It's been 4 or 5 years since I saw the video, so I'll have to do some digging. If I find anything, I'll post it back here...
            • by westlake ( 615356 ) on Thursday December 24, 2009 @01:39PM (#30545960)

              [citation needed] /morbid curiosityZ

              Stories like this always have the flavor of a urban legend.

              The automated roll bar deployment is a feature of some BMW covertibles only.

              It uses springs. Not explosives.

              Emergency services guidelines [oss.bmw.de] September 2009.

              For a full description with handsome cutaway illustrations in color click to pages 22 and 23 of the PDF.

          • I'll see your battery anecdote and raise you "about 43,700,000" for gasoline - google images car fire [google.com].
            • Yes, gasoline can burn. But it's exceptionally rare for gasoline to explode (Quick bit of trivia. A full gas tank won't explode. There's not enough O2. One that's just about empty has a higher chance of going boom)... Not to mention that AFFF (Aqueous Film Forming Foam) firefighting foam can usually stop a gasoline fire quite effectively. How do you stop a battery fire? Put water on it (AFFF is mostly water)? A dry chemical fire extinguisher? More likely, just let it burn out... I've seen more tha
              • Re:Boom. (Score:4, Interesting)

                by Ironsides ( 739422 ) on Thursday December 24, 2009 @02:00PM (#30546116) Homepage Journal

                How do you stop a battery fire? Put water on it (AFFF is mostly water)? A dry chemical fire extinguisher? More likely, just let it burn out...

                With regards to lithium batteries, just let it burn out and evacuate the area is what we do. HF is kind of dangerous and water doesn't put out lithium. It's interesting working down the hall from a battery testing lab.

          • Re:Boom. (Score:4, Funny)

            by SnarfQuest ( 469614 ) on Thursday December 24, 2009 @02:30PM (#30546304)

            What happens when you drive it over a cliff in a movie? Your typical gas powered movie car will explode in a giant fireball before it ever hits anythin on the way down (cue tire rolling out of burning wreckage). How would an all electric vehicle fare? There should be, at the least, a giant lightning bolt, St. Elmo's fire, and a Jacobs Ladder effect on the antenna. Flashes of blue light in the passengers mouths would also be appropriate, like in Star Wars.

      • Re: (Score:3, Informative)

        Actually, next-gen hybrids are and will be using various types of lithium-ion batteries and several companies, including Panasonic, Sanyo, Hitachi, and Toyota are manufacturing them. Tesla Motors already uses lithium-ion batteries in their cars.

        • Tesla motors started from scratch and that is the difference. Existing automobile makers producing hybrids right now won't switch to lithium-ion before 2012.

          • Re: (Score:3, Interesting)

            by Dare nMc ( 468959 )

            Probably also has to do with cost, the Tesla battery cost to Tesla is estimated to be $30k, and last 100k miles, so $.30/mile in battery cost alone as a upfront cost. Allowable for a "luxary" but not very feasible for "economy"

      • Dude, most hybrids out there use NiMH batteries. Sorry to give you cognitive dissonance.

        Well, most regular cars out there are filled up with gasoline. However, very few people would recommend storing enough gasoline in your basement to run your household for a week.

        • Re:Boom. (Score:5, Insightful)

          by Sir_Lewk ( 967686 ) <sirlewk AT gmail DOT com> on Thursday December 24, 2009 @12:08PM (#30545092)

          On the other hand, very many households have massive oil or propane tanks in their basements. Gasoline just doesn't happen to be all that great for heating your house.

          • Oil isn't as dangerous to store indoors as gasoline (just like less high-string battery technologies might be safer in a house).

            If people have propane tanks in basements, that's news to me. I've always seen them outside a good distance away from any buildings. A quick Google search didn't change my impression.

        • very few people would recommend storing enough gasoline in your basement to run your household for a week.

          FYI, That's about 26 gallons, so people who have attached 2 car garages do that every day. With propane it would be even easier, I wouldn't hesitate to store 2 * 15 gallon propane tanks under my bed (even if I was a smoker.)

    • by hodet ( 620484 )
      I am interested in your sump pump backup. I am looking for a solution. How long does it last? Where did you get the battery? Any info appreciated.
      • Re: (Score:3, Interesting)

        by ScrewMaster ( 602015 ) *

        I am interested in your sump pump backup. I am looking for a solution. How long does it last? Where did you get the battery? Any info appreciated.

        I got the battery itself (a Hawker 6FV11) off of EBay. Got lucky too, it was brand new in-the-box. I also picked up a 2.4Kw inverter from EBay, and a 30 amp continuous charger. I actually have two separate pumps in my sump. One of them runs from the mains, the other (with a separate float switch set a few inches higher) from the inverter. Works well, and while I've never had to run the battery all the way down, in my installation I think it would run for several days to a week, depending of course upon how

        • by fyngyrz ( 762201 )

          "mind if I sit down?"

          ...now, about this bolshoi-style ballet theater...

        • Re: (Score:3, Insightful)

          by TheCarp ( 96830 )

          Is the separate float switch for a second pump? I seem to remember the pumps themselves are not so expensive (compared to the batteries and rest of the setup). If the second float for the battery activation is on a second pump then it also helps if A) water is comming in fast enough to overwhelm the first pump (shouldn't happen generally anyway) and B) if the first pump fails

          Of course, if you lose a pump AND have more water comming in than one can handle, then, your pretty screwed anyway.

          • Re: (Score:3, Informative)

            by ScrewMaster ( 602015 ) *

            Is the separate float switch for a second pump? I seem to remember the pumps themselves are not so expensive (compared to the batteries and rest of the setup). If the second float for the battery activation is on a second pump then it also helps if A) water is comming in fast enough to overwhelm the first pump (shouldn't happen generally anyway) and B) if the first pump fails

            Of course, if you lose a pump AND have more water comming in than one can handle, then, your pretty screwed anyway.

            Yes, a second pump. It's an independent backup system in case either line power or the primary pump fails. Not infallible, but a lot better than depending upon a single pump. I did this after a power failure a few years ago almost left me with a basement full of water. Naturally, after spending all that time and energy I've never had to use it. Still, every so often I test it, and occasionally swap the power cables to the pumps to even out the wear and tear.

            I looked into those 12-volt "Ace in the Hole" t

      • Re:Boom. (Score:4, Informative)

        by Yewbert ( 708667 ) on Thursday December 24, 2009 @11:38AM (#30544824)

        Been there, done sorta that with the sump pump backup battery. You may want to consider something even more different. I have a city-water siphon pump backup. No battery needed. As long as my water supply is working, I have sump pump backup. Sure, it's not terrifically efficient, and wastes city water if it gets used - but that's cheap compared to the cleanup effort and property loss potential if my basement flooded again.

      • I saw the other response, but you may be able to source batteries locally. Check places that rebuild batteries. You can frequently find golfcart batteries (6vdc) or RV batteries (group 8D, 12vdc, 1200aH). Watch your charge cycle though. The lead acid batteries don't do so well if they're discharged below 50% frequently. Still, if you're only discharging 25% most of the time, the price is very affordable when they need to be replaced. I spent $65/ea for "rebuilt" group 8D batteries fo

    • So how about that natural gas stove, furnace, and water heater then?

      • Stove - sure
        Furnace - Not gonna work real well without electricity to run the controls and the fan.
        Water Heater - Not gonna work real well without electricity to run the controls, and the power outage may result in a lack of water pressure depending on how things are where you live.

    • by account_deleted ( 4530225 ) on Thursday December 24, 2009 @11:45AM (#30544894)
      Comment removed based on user account deletion
      • Re: (Score:3, Funny)

        by ScrewMaster ( 602015 ) *

        I don't trust lithium-ion technology enough to want something with that much capacity in my basement.

        So, you keep it in a shed. What's the problem?

        -jcr

        I don't have a big enough shed.


    • The idea of sitting atop a massive lithium-ion battery pack makes me far more nervous than I've ever been about a tank of gasoline.

      Unfamiliarity often makes people nervous. I don't exactly agree with your assessment of old=safe. You might want to look into some sense of scale.

      The average US home uses about 30 KW/h of electricity per day site [doe.gov]. A gallon of gasoline has the energy equivalent of 33.4 KW/h site [wikipedia.org]. 7 days is 210 KW/h. 210/33.4 is a little over 6 gallons of gasoline.

      That's a decent amount of en

    • There was an article a while back about why Lithium Ion batteries are not being used in cars. An oil company in the U.S. has a patent on the technology.

    • I don't trust lithium-ion technology enough to want something with that much capacity in my basement.

      I'm glad your modded insightful. I'm sure a company that makes millions of Lithium Ion batteries a year, and has partaken in very large, very expensive recalls of bad batteries has not yet fully seen the risk of putting one in a house. I'm sure their corporate Liability Insurance and Crack Legal team just figures a few hundred houses a year burning down would just be a learning experience...

      Fortunately, we have ArmChair Chemical and Electrical Engineers here on Slashdot to drum up the risk that is not obv

    • There are pure electrics (like the Tesla) and home-made plugins (like the California Prius Mods) that use LIon, but the mainstream hybrid cars you see on the street use NimH... fundamentally safer than a gas tank. Gas tanks, much like LIon batteries, are extremely explosive and flammable. Adding LIon batteries to a vehicle with a gas tank makes this even more dangerous, adding NiMH does not.

      In a home, weight is not an issue, so deep-cycle lead-acid or similar heavyweight technologies are the obvious way t

  • At room temperature and a full charge LI lasts like a whole 2 years before battery life starts to seriously degrade, unless there has been some breakthrough in LI technology that I was unaware of. Keeping it 75% charged or so maximizes battery life, but who would want a partially charged battery when the power goes out for 3 days in the dead of winter? Also what about cost? I don't really see this as a cost saving measure, but I do understand the importance of having a battery solution when you are generati

    • Re: (Score:3, Informative)

      by Jhon ( 241832 )

      You don't see it as a cost saving measure? If you can charge the thing during off-peak hours, then run your house off the battery during peek hours, that's a fairly obvious "cost saving measure".

      Of course, if you can save $1000 over two years but the battery runs you over $10000, it's not ready for prime time.

      • Re: (Score:3, Interesting)

        by ScrewMaster ( 602015 ) *

        If you can charge the thing during off-peak hours, then run your house off the battery during peek hours, that's a fairly obvious "cost saving measure".

        You're right, of course, but the power companies will find a way to take those savings away from you if this becomes popular, you know that. Well, at least the one in my State certainly would, that is, if they didn't get a law passed to make home power storage flat-out illegal. Wouldn't put that past them either. They're bloodsuckers: for example, manufacturers that try to set up self-generating facilities to save money generally find themselves in court. Power companies are like record companies: they don'

    • by iluvcapra ( 782887 ) on Thursday December 24, 2009 @11:21AM (#30544634)

      who would want a partially charged battery when the power goes out for 3 days in the dead of winter?

      I would, since the status quo is no battery at all.

      • by slyn ( 1111419 ) <ozzietheowl@gmail.com> on Thursday December 24, 2009 @11:47AM (#30544908)

        who would want a partially charged battery when the power goes out for 3 days in the dead of winter?

        I would, since the status quo is no battery at all.

        The cool kids on the block already have natural gas generators hooked up to their houses in the case of power outage, and I would guess that a natural gas generator would last significantly longer at a significantly lower TCO than any currently available battery technology (when at the scale of powering a house).

        • Right, I'm from Minnesota and a lot of people would have heating oil tanks in the back yard -- there's all kinds of solutions to this problem. The cleverest thing to do would be to arrange your home's power management in such a way that you don't need current to run most of the functions in the cold. Just about every appliance in the house can be run with gas but for the fridge, and in the winter it's pretty easy to see to that by just keeping it in an unheated part of the house.
    • if its for home use i dont see why the form facto is so big of a deal. i understand space constraints in JP but in the US anyway, a battery the size of a trashcan could probably be stored in a suburban garage with no concern whatsoever. i would think that even in Japan you could get away with a battery the size of a microwave oven without too much hassle. in these instances we would be talking about kWh rates that would be sufficiently large to make a significant impact on global warming. yes you heard me r

  • Tense (Score:4, Insightful)

    by Dunbal ( 464142 ) on Thursday December 24, 2009 @11:09AM (#30544530)

    We go from the future:

    "Panasonic has announced plans to create 'home batteries."

          That is, the batteries don't exist yet.

          BUT:

          Also, you can buy energy when it is cheapest [only there's nowhere to store it at the moment], and don't need to worry about power outages anymore [well actually you still have to worry, because they haven't actually invented the battery yet].

          Who wrote this? I see a brilliant future for you writing prospectuses for investment bank companies. This is just hype. I for one will not be buying the $150k batteries that need special zoning permissions and need to be replaced every 3 years.

    • Re:Tense (Score:4, Informative)

      by jfengel ( 409917 ) on Thursday December 24, 2009 @11:19AM (#30544616) Homepage Journal

      Who wrote this?

      Some Guy In A Blog, apparently. It's attributed to Fumio Ohtsubo, President of Panasonic (under a different, less common spelling) but links to no press releases or speeches.

      Ohtsubo did an interview about Panasonic working on a kind of fuel cell/LiIon hybrid battery and making a $1B investment (in 2012!) in home power systems, including solar. Here is a link to an actual reputable news source rather than a blogger with poor reading comprehension skills:

      http://www.bloomberg.com/apps/news?pid=20601101&sid=ajhto3eO4fpM [bloomberg.com]

      • That makes way more sense than the original blog. According to your FA, Panasonic is shifting focus to intermediate power supply / control

        The new technology will let consumers monitor their own electricity use and display the data on television sets, Ohtsubo said. The system will be able to connect and monitor all of the appliances in a house, and the solar panels may produce enough clean power to offset any carbon dioxide created from other power the appliances use, he said.

        Batteries seem to be but a pa

  • source? (Score:2, Insightful)

    by Anonymous Coward
    Can we get an actual source, not one that injects pointless banal commentary, and actual shows where they got their information? kthxbai
  • Saving money (Score:3, Insightful)

    by DreamsAreOkToo ( 1414963 ) on Thursday December 24, 2009 @11:12AM (#30544544)

    Wow, I can save pennies off my electricity! Now, how many centuries does it take for the battery to pay itself off?

    • Not only that, how long does it last(lifespan)?
      How much energy/cost is used to manufacture it?
      How much energy/cost is used to mine the components?
      Is the government planning on subsidizing and creating and artificial market?
      It is like the idiot "liberal" on TV I saw who was asked where the electricity came from for the electric car.
      His Answer: "The Wall", I damn near had a brain aneurysm explode from the stupidity.
      • by Binestar ( 28861 )

        It is like the idiot "liberal" on TV I saw who was asked where the electricity came from for the electric car. His Answer: "The Wall", I damn near had a brain aneurysm explode from the stupidity.

        Was this a pop-news show where the normal audience would be wondering if they needed a "special" circuit run or a more technical audience? Either way, the question of where the electricity comes from is rather silly. We're all pretty much on the same grid in the US. So even if the power I'm using is generated with one thing, I always consider it as a percentage of each type generated in the US. We all share our sources. I say: Build more nuclear plants and reprocess the current waste. Hell, build one

  • FTFA:

    Panasonic is going to create one of the hottest batteries available to date.

    Wow, after all the exploding battery stories, I can't wait to have this model in my house. Does anyone actually proofread these articles?

    I'm not interested in storing energy for a week, but if I can have one of these hooked to a smart meter, and get a rate reduction for allowing this battery to reduce demand from the grid during peak hours, I' d be very interested. That battery could even be a lot smaller (and cheaper) then the whole-week version.

  • The page linked to is an ad laden (carefully selected related items, yeah right) mess that has this third or fourth hand. Even physorg just has a press release that mentions the battery and focuses on Panasonic acquiring Sharp and how harsh the corporate environment is.

    How big is this thing? What is it's capacity? Is that a Japanese house, or a North American one?

    • Panasonic acquired Sanyo, not Sharp, dont repeat facts unless you're gonna get them right

      • by ceoyoyo ( 59147 )

        Hey, I could be a blogger!

        • true true, sorry if i sounded harsh.

          • by ceoyoyo ( 59147 )

            No, I should have checked. I originally thought "Samsung" but knew that couldn't be right. But I just couldn't face that page again.

            A lot of crimes have been committed against/with the web, but setting words in articles to automatically pop up windows with definitions/advertising/random spam has got to be one of the worst. Even supposedly reputable organizations (is it the NY Times?) seem to feel their readership need every second word wired with an in your face definition.

    • The page linked to is an ad laden (carefully selected related items, yeah right) mess that has this third or fourth hand.

      True. The source is a badly written Bloomberg story [businessweek.com] which says the new battery has a capacity of "3.4 amperes per hour". I wrote to the reporter pointing out the meaninglessness of that number. The useful numbers for battery technologies are $/KwH and Kg/KwH, and they don't have those. The only useful piece of information in the story is that Panasonic will make a real announcement

  • The disadvantage is cost. There are many battery technologies more suitable for this application than lithium.

  • Vaporware (Score:5, Informative)

    by mi ( 197448 ) <slashdot-2017q4@virtual-estates.net> on Thursday December 24, 2009 @11:27AM (#30544704) Homepage Journal
    Emphasis mine:

    Panasonic has announced plans to create 'home batteries.' They are lithium-ion batteries large enough to power a house for a week, making energy sources such as solar and wind power more feasible. Also, you can buy energy when it is cheapest, and don't need to worry about power outages anymore.

    Sorry, but if they have only just "announced plans", then, for the foreseeable future, I still can not power a house for a week, and I still need to worry about power outages.

    Wake me up, when I can pick these up at Lowe's... Or, at least, order them online somewhere...

    Indeed, TFA [nexus404.com] itself uses the proper tenses and gives the ETA for what currently can only be called "vaporware":

    Panasonic is going to create one of the hottest batteries available to date. The new lithium-ion storage cell should power up a whole house in 2011 when it could be available to the general public. [...] No specific details about the future home battery from Panasonic have been given yet. In two years time we should know more about the device and Panasonic will definitely want to periodically show everyone its progress.

    CmdrTaco, WTF?..

  • I'm going to need a 16,000Ah rating at 48V, plus a 100kW inverter to power my 1600SF, 1960s ranch. Granted, it's not the most efficient home ever built, but it's all electric (yes, it's been upgraded to 400A/240V service, and I really do run through 800kWH a week during cold winter periods...which is when the electricity is most likely to fail).

  • Other considerations (Score:4, Informative)

    by satsuke ( 263225 ) on Thursday December 24, 2009 @11:33AM (#30544772)

    Some of these technologies are of no use to those of us that live in areas where the cost of energy is consistent all day and night and year round.

    Part of that maybe the problem (no intelligence in the infrastructure). But in the meantime if I were to have solar or any other resource put up that would benefit from stored energy for later use, it'll throw the payback vs normal utility curve way off to where I'd have to live here for decades to get my money back in anything but smugness.

    As far as LI battery technology, it seems that the Prius used NMhd batteries because the number of charge discharge cycles was greater, since the batteries in the story were expected to have a cycle per day, the owner would have to replace them realistically every 3-4 years.

    As far as the greater energy content of LI batteries, that is a risk that is always present with batteries. As long as the controller / charger is smart and has a layer or two of fault checking, the risk of runaway thermal events is pretty low. (The problem people had with Lithium Ion AA cell batteries where they are available was when people put them into standard NiCad or NiMh chargers, which apply too much current too quickly and make them pop to start fires. Since this is an integrated system by Panasonic with no capacity to mix and match technology evident, I'd say the risks is low.)

    It would be possible with standard deep cycle lead acid batteries, but than you have to have climate control for your batteries above and beyond that proposed, and than your dedicating a good chunk of floorspace to batteries (You can't stack them because of heat buildup when discharging). I know the Central Offices I've been in have had a good chunk of their floorspace dedicated to just power, and even than only for the few minutes it takes for the diesel to kick over .. and you don't want to know what happens to expensive telephone equipment when it starts getting fed progressive amounts lower than 48VDC.)

  • by x_hexdump_x ( 525534 ) on Thursday December 24, 2009 @11:41AM (#30544850)
    Large UPS are common for data centers. But they are expensive and time consuming to maintain. In a data center the cost and time are justified. But for a home I would question the value.
  • Wrong technology (Score:5, Insightful)

    by Mprx ( 82435 ) on Thursday December 24, 2009 @11:45AM (#30544890)
    The only advantage of lithium batteries is high energy density, which is irrelevant for a static installation. For powering something as long lasting as a house it would be better to use something more robust. Nickel-iron [wikipedia.org] batteries have low energy density but are very robust. I wouldn't want a house battery I'd have to replace every few years.
    • I would suggest sodium-sulfur for a static installation. Cheap, with high energy density. Keep it well insulated though, because it needs to stay above 300C.

      For anyone worried about sodium fires: compared to lithium batteries? Seriously? Or any battery that can power a house for a week, for that matter?

  • by adipocere ( 201135 ) on Thursday December 24, 2009 @11:45AM (#30544892)

    I'd prefer an EESU from EESTOR (if that ever happens), since it would be cheaper on a buck-per-Joule level and it would last for a very, very long time. Second to that, nickel-iron batteries, which are heavy and inefficient, but survive much abuse and have working lifetimes far longer than that of most other batteries. Pity they are no longer made in the United States; much of their price is presumably in just shipping them here.

  • While this was staged for demonstration purposes, it demonstrates the power Lithium Ion batteries can expel when they fail.

    http://www.youtube.com/watch?v=WeWq6rWzChw

    Pretty sure I don't want a huge one of these in my basement...

    • by PPH ( 736903 )
      Perhaps there are better battery chemistries that we should be pursuing. I purchased a solar-powered gizmo that uses a Lithium Iron Phosphate [wikipedia.org] battery. While the conventional Li-ion batteries have somewhat higher energy to weight ratios, this isn't as important for something sitting in one's basement as it is in a laptop you've got to lug around all day.
  • by presidenteloco ( 659168 ) on Thursday December 24, 2009 @11:55AM (#30544974)

    For the purpose of storing intermittent wind and solar power,
    the electric utility companies could use mass installations of
    these batteries. Assuming they don't have hydro dams to
    run in reverse using the wind and solar, that is.

    Just like it doesn't actually make sense for everyone on your block
    to own a lawnmower or circular saw or carpet steam cleaning machine,
    it doesn't really make economic sense for everyone to have their own
    batteries either. A central utility could buy and maintain batteries
    with economies of scale.

  • by fluffy99 ( 870997 ) on Thursday December 24, 2009 @01:00PM (#30545578)

    Also, you can buy energy when it is cheapest

    You can charge them at night if your power company has lower rates at night. It's pointless though as any savings in the cost disappear in the inefficiencies of the ac->dc for charging, the heat losses during charging, and the dc->ac conversion to use that power again. A 10% savings in the power cost is stupid when you give up %15 of the energy trying to save it.

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