Tesla Home Battery Details Emerge



Details about the Tesla home battery are beginning to emerge. Is that what Elon Musk was hinting at when he Tweeted a few days ago about a major, non-automotive announcement coming on April 30? We don’t know, of course, but most Musk watchers think that’s what the hoopla is all about.

According to Benzinga, Trip Chowdhry, a stock analyst for Global Equities Research, has sent a note to his investors with some details. He claims 230 California homes currently have a Tesla home battery installation and that there are another 100 in homes in other states.

Want details? OK. Here’s what one of the homeowers who claims to be testing the Tesla battery told Chowdry:

  • The Battery has to be installed 1.5 feet above the ground, and should have an open space of 1 ft on all sides.
  • The battery does not make any noise, does not need any maintenance, and has no drippings.
  • The Battery includes the inverter.
  • The battery is about 3 ft tall and 2.5 ft wide and looks good.
  • The installer offered a choice between a 10 kWh and 15 kWh. He opted for the 10 kWh battery.

Price for the 10 kWh battery is said to be $13,000. At present, the local utility, Pacific Gas & Electric, is offering a 50% rebate. This particular homeowner opted for a payment plan that called for a down payment of $1500 and monthly payments of $15 for 10 years. But here’s the kicker. He charges the battery at night when electricity costs are lowest and sells it back to PG&E during the peak demand times every day. He says he makes $12 – $15 a month doing that, which pretty much covers his monthly payment.

Here’s more interesting tidbits Chowdry says he learned from the Tesla battery customer:

  • The battery can be controlled from an iPhone, and has a web application also.
  • The battery is set to charge from a solar system until fully charged and then send energy back into the grid.
  • Fully off Grid. The battery can be charged by a regular generator also.
  • He has not had any problems with the Battery System…and gets over the air wireless software updates frequently.

That is all very exciting news. But be warned. Not every utility is as generous with its rebates or willing to take back electricity from homeowners as PG&E. Part of that willingness is spurred by mandates from the California government that require them to get 33% of their electrical power from renewable sources by 2020. Not every state is as focused on environmental issues as California is. And many utilities are outright hostile to home solar power in general.

In other words, as we car people are fond of saying: “Your mileage may vary. See retailer for details.”

Image: Tesla Motors forum member myI55

About the Author

I have been a car nut since the days when Rob Walker and Henry N. Manney, III graced the pages of Road & Track. Today, I use my trusty Miata for TSD rallies and occasional track days at Lime Rock and Watkins Glen. If it moves on wheels, I'm interested in it. Please follow me on Google + and Twitter.
  • BlackTalon53 .

    $13k for 10kwh? Whoa.

    A Model S battery would have to cost 110,000 dollars then (8,5x$13k) … and this box has lower performance cells, no “skateboard” armour and, I suspect, no climate control. Can that price be correct?

    • Bataleon

      Agreed. $1300 per kWh seems darn steep. According to this [1] article Model S batteries cost around $500 per kWh. Here’s hoping.

      [1] https://fortune.com/2014/09/18/sakti3-lithium-ion-battery/

    • RAMGarden

      This isn’t just a battery. It’s also got the inverter and some other type of computer with WiFi or similar network connection hardware (the customer mentioned it gets over the air updates). So there’s no real way to compare it to a Model S battery.

    • Joe Viocoe

      Is that installed price?

    • Steve Hanley

      Details are extremely hard to come by. Some factors may include the fact that this installation is a few years old and prices have come down somewhat since then. Also, Musk is savvy businessman. If PG&E is kicking in 50% and the federal government another 30% on top of that, who cares how much the darn thing costs?

      The important thing for the customer is that he got his home battery for $1500 and a paltry $15 bucks a month.

      We’re gonna hear a whole lot more about this in the coming months. And keep in mind, Tesla is not the only battery maker looking to get in to the home storage market. No one else makes a car quite like the Model S but quite a few companies make home storage batteries.

    • Jim Smith

      inverters are expensive

  • UncleB

    This is the beginning of the end of centralized power and the huge political mesh that entails . . .

    • Steve Hanley

      Hope your right, B. But the utilities are not going to go down without a fight. This could get ugly.

      • Jim Smith

        oh it will. it will….

        • georgeodjungle

          not even close. @ a 90% loss not smart unless you want to pay $2.00 a kw add solar then it’s $4.00 a kw = another greeny rip off
          simple math folks

          • Jim Smith

            keep dreaming utility shill.

          • georgeodjungle

            simple math called ohms law
            you only get <10% of advertised,,,like solar pv

          • Phoc Que

            U having no brain is not smart

          • georgeodjungle

            u r so cute
            calling names with counter points nor facts.
            thanks for the win

          • Phoc Que

            Are U a retard???

  • Bike And Golf

    Wow, if this works as told – could really change things. BS on those who think utilities are scared, this is a win-win. Utilities now have an outlet for cap and trade, and will not have to build or worry about modernizing old plants. The infrastructure will always need to be maintained by a utility.

  • DesiLurker

    I applaud the product & the end to power centralization it brings, however, the numbers dont make sense, check the following math:
    total price paid for battery is 1500 + (15*12*10) = 3300.
    for 10kwh pack it works out to $330 per kwh. somewhat high but reasonable!
    OTOH the arical state 10kwh is $13k so $1300 per kwh. so which is it? If its latter then its clearly a scam as that’s not the price paid for any batterypack in years & esp the fact that battery can be lower quality & may not need som much packaging expenses.

  • Shiggity

    Love the generator option.

    I like the idea of generator + battery + solar / wind.

  • Pingback: Clean Energy Revolution Is Ahead of Schedule | Turn Your BrandON()

  • kevin mccune

    Perhaps when we harden the grid,this will help prevent power outages and by the way,if this thing lasts long enough,energy self sufficency shall become a reasonable goal.
    I just cant see my home state getting on board with this however.

  • Paladingrad 1992

    An old idea that has come back around. Farms in the early 1900’s used a gasoline generator that was run periodically to keep storage batteries charged, which in turn powered the home.

  • 小杜 (xiao du)

    Lithium Iron Phosphate works best in the >20% <80% usage range (i.e 60% usable capacity).CALB 3.2v / 180Ah is about $65 at the moment in China from suppliers (RMB400 odd)

    [3.2v * 180Ah @ 60% usable = 345W/hr per 65$ so about 190$ per *usable* KW/hr, or 576W/hr per 65$ actual capacity / $115 per actual KW/hr capacity]

    Tesla's 10KW is probably not capacity, but *usable* storage, so you're looking at something like 16KW of actual storage capacity.

    So assuming 10KW = 16KW storage, you're looking at about 32 batteries, or about 2000$ +- worth of battery. Probably 8 x 3.2 = 25.6V (24v) x 4 to give you 720Ahr @ 24v

    They're obviously going to be using higher capacity batteries, but pricing should be similar. Pricing for storage is only headed down…

    • georgeodjungle

      +10% loss each battery in parallel

      • 小杜 (xiao du)

        Maybe for Lead Acid, but not for LFP.

        • georgeodjungle

          the type doesn’t matter. + you only have “like solar” <10% usable power. it's a ohms law thing

        • georgeodjungle

          yes & is the reason you can’t let a tesla car sit or it’ll self drain to a dead battery

          • 小杜 (xiao du)

            Not particularly correct, all batteries self discharge.
            You seem to have a few misconceptions about things.

          • georgeodjungle

            self discharge way faster in parallel:also falls under ohms law. I’m 100% correct if you don’t understand I can explain it to you better. theres simple experiments you can do

    • georgeodjungle

      on your #s what would you say is the volts on A fully charged battery & the volts on say the average daily low battery

  • georgeodjungle

    joke of the day just got longer.
    just 1 more thing to add to the list: NEVER hire a person that has PVs, hybrids, ecars & now the home battery why? they’re void of simple observation, critical thinking & high school math.