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Power The Almighty Buck Hardware

Tesla's Household Battery: Costs, Prices, and Tradeoffs 317

Technologist Ramez Naam (hat tip to Tyler Cowen's "Marginal Revolution" blog) has taken a look at the economics of Tesla's new wall-mounted household battery system, and concludes that it's "almost there," at least for many places in the world -- and seems to already make sense in some. From his analysis: For some parts of the US with time-of-use plans, this battery is right on the edge of being profitable. From a solar storage perspective, for most of the US, where Net Metering exists, this battery isn’t quite cheap enough. But it’s in the right ballpark. And that means a lot. Net Metering plans in the US are filling up. California’s may be full by the end of 2016 or 2017, modulo additional legal changes. That would severely impact the economics of solar. But the Tesla battery hedges against that. In the absence of Net Metering, in an expensive electricity state with lots of sun, the battery would allow solar owners to save power for the evening or night-time hours in a cost effective way. And with another factor of 2 price reduction, it would be a slam dunk economically for solar storage anywhere Net Metering was full, where rates were pushed down excessively, or where such laws didn’t exist. That is also a policy tool in debates with utilities. If they see Net Metering reductions as a tool to slow rooftop solar, they’ll be forced to confront the fact that solar owners with cheap batteries are less dependent on Net Metering. ... And the cost of batteries is plunging fast. Tesla will get that 2x price reduction within 3-5 years, if not faster.
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Tesla's Household Battery: Costs, Prices, and Tradeoffs

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  • Not Actually $3500 (Score:5, Insightful)

    by sonicmerlin ( 1505111 ) on Sunday May 03, 2015 @07:31PM (#49608169)

    I don't know how this guy wrote the entire article without realizing it, but as Tesla explained in a Bloomberg article the cost of the 10 kWh battery's full installation plus inverters is $7100, not $3500, if you buy outright, and $5000 if you lease. It's just way too expensive. Battery tech needs to come down to under $100/kWh to become more mainstream, and solar panels need to drop to about half or even less of what they are now.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Errr doesn't installing the solar panels pretty much mean you also get the inverter?

      • by Phreakiture ( 547094 ) on Monday May 04, 2015 @08:19AM (#49610815) Homepage

        The inverter design used for battery systems and for solar power systems differ significantly. There are some that can do both, but they're not the ones being used by the majority of solar installers.

    • by catchblue22 ( 1004569 ) on Sunday May 03, 2015 @08:25PM (#49608397) Homepage

      Companies like SolarCity basically install solar systems for no money up front, and then lease them back to you for a period. For many houses, even with these fees, the SolarCity systems will save the homeowner quite a bit of money. Licenses to sell power back to the grid are usually restricted, even in states they are allowed. If you have a battery system installed, you will no longer have to sell your excess solar energy back to the grid. You'll simply be able to store it in your battery for later use. Thus, homeowners with these systems may not have to apply for licenses for their solar systems, since they will not be doing net-metering. This will allow many users to install solar panels who couldn't before. It removes the ability for utilities and/or state governments to restrict the number of homes with solar panels. This is why these batteries will likely have a huge impact.

      • by jblues ( 1703158 ) on Sunday May 03, 2015 @09:16PM (#49608559)

        Companies like SolarCity basically install solar systems for no money up front, and then lease them back to you for a period. For many houses, even with these fees, the SolarCity systems will save the homeowner quite a bit of money. Licenses to sell power back to the grid are usually restricted, even in states they are allowed. If you have a battery system installed, you will no longer have to sell your excess solar energy back to the grid. You'll simply be able to store it in your battery for later use. Thus, homeowners with these systems may not have to apply for licenses for their solar systems, since they will not be doing net-metering. This will allow many users to install solar panels who couldn't before. It removes the ability for utilities and/or state governments to restrict the number of homes with solar panels. This is why these batteries will likely have a huge impact.

        Here in the Philippines, its allowed for any homeowner or business to sell electricity back through the grid. It took me a lot of research to find this out - its not widely publicized at all, and I haven't seen many folks taking the option. It could be a great option given pretty good (2200 hours) of sun per year and very high priced electricity, which as it happens is often used for cooling during the day. I guess that given a per capita GDP of something like $7000/year most people can't afford this yet. . . On the other hand much of the commercially produced electricity is from renewable sources, particularly hydro and thermal, but some of the small villages have their own solar plant - provides only enough for basic needs.

        As it happens we have not a smart meter in front of the house, but one of the old magnetic kinds that will (AFAIK) happily run in reverse.

        • Yes, but are you allowed to sell back at the rate you purchase electricity? Because if its 10-30x reduction, battery is worth more.

          • by jblues ( 1703158 )

            Yes, but are you allowed to sell back at the rate you purchase electricity? Because if its 10-30x reduction, battery is worth more.

            I'm not actually sure, but I doubt it would be the same rate as purchased. Off-grid with storage sounds like its becoming more and more attractive. . Myself, I haven't bought the PV cells yet, but its something I want to do in the next year or two. I'm also looking for better solutions to staying cool - that's where most of our electricity goes.

          • by funwithBSD ( 245349 ) on Monday May 04, 2015 @10:11AM (#49611959)

            In my case it is 3.2c vrs 19.2

            But here is the thing: You push 10kWh on the grid during the day, you can draw that 10kWh for a net zero cost, and 32c "profit".

            In essence, I don't need a battery, I get one for free and it is called "the grid"

      • Companies like SolarCity basically install solar systems for no money up front, and then lease them back to you for a period. For many houses, even with these fees, the SolarCity systems will save the homeowner quite a bit of money.

        No, SolarCity doesn't lease the panels back to you - they sell the power from the panels to you. And they control the rate you pay and have the ability to raise it annually (up to 2.9% per annum).

    • Inverters in this case are a sunk cost. You would end up with them regardless if you go battery storage or net metering.

    • by Khyber ( 864651 ) <techkitsune@gmail.com> on Sunday May 03, 2015 @09:41PM (#49608633) Homepage Journal

      Plus inverters? No. Plus inverter. That pack, if you look at the specs and do some math, is good for a single ~20A 120V circuit, given that it's sustained discharge is ~2kWh and peak is 3kWh. Reality is more like 15A. I wouldn't trust that pack for more than one room of my home. One for each room and multiple for the kitchen given the power drain an electric stove does per burner, be it element, induction, or IR, microwaves, dishwasher, refrigerator...

      • by Ozoner ( 1406169 )

        Or you could do a little research and learn that using solar electricity to generate low grade heat (eg cooking) is an idiotic waste of high grade energy.

        Solar requires a little intelligence and a willingness to conserve energy. Clearly it's not for you.

        • by Smidge204 ( 605297 ) on Monday May 04, 2015 @05:07AM (#49610023) Journal

          It's not an idiotic waste of energy if:

          1) The energy would otherwise come from other, equally high grade (or even higher grade) energy sources, e.g. natural gas

          2) The energy would otherwise come from non-renewable sources, e.g. natural gas

          3) The energy would otherwise not be used at all due to overproduction

          The monetary value of electricity flowing back into the grid on net metering is extremely low - much lower than the cost to purchase that electricity from the grid. If you have a choice between selling the power to the grid or using it to "generate low grade heat" with an electric stove, then the stove wins just on financial grounds.

          If your argument is that you could use direct solar thermal methods to generate that heat - skipping the conversion to electricity - then sure it would be more efficient that way. When the source of energy is free, however, and you have already invested in the infrastructure for other reasons, it makes perfect sense to utilize solar electricity for cooking and cleaning. The alternative is to invest even more on additional infrastructure to utilize the same free energy source in a moderately more efficient way.

          Use it or lose it, as they say.
          =Smidge=

          • by Rei ( 128717 ) on Monday May 04, 2015 @06:03AM (#49610147) Homepage

            Burning natural gas, aka heat, is not a "higher grade" energy than electricity, it's a lower grade energy. Electricity can be converted losslessly into heat. Turning heat into electricity loses a large chunk of it.

            I agree though that 2kW sustained / 3kW peak is too low for most people - even if they don't use an electric stove. Yes, one can arrange to not use multiple high consumption devices at the same time, but the goal needs to be to not make people's lives more complicated. It's so easy to forget what you have going, too... I always forget that I can't run my microwave and my electric kettle at the same time because they're both on the same circuit and combined it's too much power consumption.

      • by Twinbee ( 767046 )
        Wait, did you not mean kW instead of kWh? I was only just recently moaning about that in another thread.
    • by Guspaz ( 556486 )

      You're quoting Solar City's pricing, not Tesla's, which would include various markup. That is not Tesla's pricing, and other installers may use different pricing for install and inverters.

    • by radl33t ( 900691 )
      Solar panels are cheap enough (0.6 $/kWh), and they will get ~35% cheaper over the next 3-4 years as new PERC cell upgrades improve efficiency for the same module cost. Installing them needs to come down to levels that exist in other civilized countries, anything but utility scale installation is still a rip-off by profiteers. 125 $/kWh for batteries is enough, that is only 7% reduction per kWh for 6 years. I bet we hit it by 2020. Especially if Chinese start making city-factories. With these two things, o
  • Why? (Score:4, Funny)

    by Anonymous Coward on Sunday May 03, 2015 @07:35PM (#49608179)

    Coal is far more cost effective.

    • Re:Why? (Score:5, Funny)

      by R3d M3rcury ( 871886 ) on Sunday May 03, 2015 @07:43PM (#49608211) Journal

      Yeah, but it's pretty messy. I mean, have you ever shoveled coal? I wouldn't want that in my house.

    • Re:Why? (Score:4, Insightful)

      by dittbub ( 2425592 ) on Monday May 04, 2015 @12:29AM (#49609137)
      People want to get off fossil fuels. Its not a matter of which is more cost effective. Its a matter of how affordable solar and battery is. Its clear the technology has nearly arrived such that if a middle class household wanted to get off the grid, off coal, off gasoline for their car... they can do it and afford it. Even if its still more expensive, its within their reach where it wasn't before.
  • Time (Score:5, Insightful)

    by rtb61 ( 674572 ) on Sunday May 03, 2015 @07:45PM (#49608221) Homepage

    Time will alter everything. Reality is, the more batteries produced the cheaper they will become and much more interestingly, the more batteries installed, the fewer people paying for electrical mains infrastructure, the much more expensive per user it becomes. That economic boulder rolling down a hill, faster and faster and faster, inevitable. Tesla still needs to do a complete system, ready to install by franchised installers (ensure quality installs), keep it simple. Not to forget, the Tesla power pack would be a strictly utility device, much like adding air conditioning, or a verandah, it adds capital value to the property. So forget the incumbent PR=B$ about measuring it against electricity charges because that is only part of it's value, it has real capital asset value and that value also needs to be added in, to more effectively compare it what is in affect rent and burn (rent your part of the infrastructure and burn your capital inputs).

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      >the more batteries produced the cheaper they will become

      i simply don't belive it. the same argument was used to justify subsidies for electric cars, yet they still don't make economic sense and are more of a novelty or rich person's toy. therefore, i don't except your premise that economics of scale can be achieved. there is no shortage lithium ion battery production.

      the only thing that will bring the price down is a technological break through. and that may never happen.

      • Re:Time (Score:4, Interesting)

        by 140Mandak262Jamuna ( 970587 ) on Sunday May 03, 2015 @08:20PM (#49608387) Journal
        Problem with electric car is the range anxiety and recharge time. Economically they are very much viable, The brainpack that built the first Tesla have cashed in their stock options and have branched out. They are taking pot shots at all vehicles that have stop-and-go use, with long stops in between. School buses, garbage trucks, delivery trucks, postal vans etc. Quick change battery packs are being designed too. I think electric vehicles will start showing up at the unexpected places.
        • Re:Time (Score:5, Interesting)

          by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Sunday May 03, 2015 @08:54PM (#49608483) Homepage Journal

          I think electric vehicles will start showing up at the unexpected places.

          I think the place they will dominate first (and next, I guess) is motorcycles. The only thing missing from most current electric motorcycles is top speed. Most people don't ride long distances on them, so it's an ideal kind of vehicle to hit next.

          • Re:Time (Score:4, Interesting)

            by BlueStrat ( 756137 ) on Sunday May 03, 2015 @10:37PM (#49608827)

            I think the place they will dominate first (and next, I guess) is motorcycles. The only thing missing from most current electric motorcycles is top speed.

            Prepare for major E-cycle-gasm. 140 miles per charge highway, 230 city. Full charge time 1 hour. Insanely fast.

            https://youtu.be/W1CSdYsJIWQ [youtu.be]

            Even this one is reportedly quite fast, and being a replica of a "light cycle" from the movie "Tron", it *should* come with a gold-plated Nerd Card included.

            https://youtu.be/6aC57JeJt44 [youtu.be]

            They also makes more cosmetically-conventional (and affordable/practical) models as well.

            Strat

          • Re:Time (Score:5, Insightful)

            by thesupraman ( 179040 ) on Sunday May 03, 2015 @10:44PM (#49608871)

            Honda CTX700 already gets 64 MPG in a reasonably large/comfortable commuter bike.
            The Honda GROM 125, which is more compact, is being reported by users at over 100MPG

            There is significantly less room for electrics here, since bikes can already quite easily be very efficient, and
            the added weight as a percentage of total mass is much higher than a car.

            Sure, there is a niche, but thats already pretty well catered for with steppies, and those are often already
            around 100MPG at 'city speeds'

            Touring/Cruiser/etc bikes dont want electric on the whole (except again in a marketing niche). Harley etal already
            intentionally put piss poor engines in their bikes for pure marketing reasons, with horrendous fuel economy, terrible
            performance, and horrible weight - because thats what the market demands.

            Electric bikes will exist in cities for noise/political reasons, and as a fashion niche, but will not become commonplace
            for some time.

      • actually the price of the leaf and volt have pretty much gone down every year since they have been out. so it is in fact getting cheaper as discussed
      • Re:Time (Score:4, Interesting)

        by silentcoder ( 1241496 ) on Monday May 04, 2015 @12:31AM (#49609139)

        Your example fails.
        Electrical cars are already much cheaper than they were a few years ago. In fact every study has found the TCO of the Model-S is the lowest of any car in it's class. It's cash-price is currently at the top-end of the luxury-sedan class but it's TCO is way below anything else in the same price-range, you make a LOT back in saving on fuel and maintenance (maintenance on an electric car is much lower - even your brake pads last years longer because of regenerative breaking, and there are so many fewer mechanical parts that can wear out). There's a reason why BMW brought out the i8 for example, the other car companies can see the writing on the wall and are desperate to stay in the game.

        They are also, once again, proving the futility of not being leaders anymore. While they are trying to build Model-S killers, Tesla is already seeing the Model-S as just the foot-in-the-door model, they are already working on both an economy car and an SUV model. Expect the same pattern on release, slightly more expensive cash-price when you first buy it, but a LOT more value for that money, and a lower TCO due to savings over time.

        What you're describing right now is incredibly short-sighted, give it another 2 years and then you can start comparing. Based on current data, if electric cars are not the vast majority of the market in 10 years I would be incredibly surprised and I would say that for that to happen something else entirely we've not even seen yet would need to take over the market, it sure as hell won't be ICE's.
        Trust me, ten years from now the only ICEs that may still be on the roads will be classic cars and long-haul heavy-load delivery trucks.

        • It's cash-price is currently at the top-end of the luxury-sedan class

          In among all your handwaving about TCO - the above quote is the single relevant fact.

          Your example fails.

          On the contrary - the grandparent is correct, electric cars are the plaything of the rich because you pay the cash price upfront. TCO is irrelevant to what the bank loans you.

          Trust me, ten years from now the only ICEs that may still be on the roads will be classic cars and long-haul heavy-load delivery trucks.

          Only if so

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Its a depreciating asset at best and adds almost no value to property.

    • Re: (Score:3, Informative)

      "the more batteries installed, the fewer people paying for electrical mains infrastructure"

      non sequitur. You still need to load the bateries. Doing it without support from your mains is a big if.

      • by rtb61 ( 674572 )

        The biggest energy demand in a house, air conditioning (fully air-conditioned, not just one room), any idea at all how many HP (horse power for slow Americans, rather than kW) a large domestic air conditioning unit is (single digits) and now compare that to the HP of car (triple digit). So power to spare in some locations, not all (yep, snow is a real problem). So for most locations no if and you choose whether or not to take the risks but when others don't that energy insurance will get expensive (likely

        • by Cyberax ( 705495 )
          Air conditioning is pretty efficient. A 3kW (electric) unit can provide about 6kW (thermal) of cooling power which should be enough for most houses in most of the US during the night. And during the day you can use the nice friendly Sun to power your air conditioner directly.
  • by Anonymous Coward on Sunday May 03, 2015 @07:53PM (#49608249)

    All the discussion I've seen about this Tesla announcement has focused on [1] time-shifting electricity demand and [2] storing electricity from on-site generation. Those are the major uses, no argument. But another one is serving as a whole-house UPS. In some parts of the US (like the NE, where I live), a LOT of people have gasoline or natural gas/propane generators that automatically kick on when the power goes out. Many of these system, which are often as expensive or more so than Tesla's battery system, get pressed into service only a couple of times per year, and then for a couple of hours. A battery system can't replace a generator for long outages, of course, but for short-term issues, this is a non-trivial extra benefit.

    • by fnj ( 64210 )

      The outages that only last a couple of hours are nothing more than a nuisance. When it starts reaching a day or more, it becomes a goddam nightmare. Without the well pump, you have no running water. Without water, you cannot flush the toilet. The refrigerator contents start to spoil. In the winter you have no heat. Residual water in the pipes can burst.

      I would be perfectly happy with just the essentials. Well pump, furnace, and refrigerator. A 2 kW source with enough surge for motor starts would be enough.

  • by BenJeremy ( 181303 ) on Sunday May 03, 2015 @08:03PM (#49608299)

    Musk knows that to reduce the cost of EVs, the cost of making batteries has to go down, and the easiest way to do that, AND the best way to build up infrastructure, is to ramp up production.

    That's what this is all about - not about making money, at least in the short term. Tesla just needs to have sales drive (and justify) the increase in production, and when the price of making those batteries drop, EV sales will become more attractive to a larger customer base, thus ramping up production more... rinse, lather, repeat.

    • No, the easiest way to bring battery prices down is to use a different chemistry. Li ion is spectacularly unsuited to a stationary battery.

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        His aim is not to bring down the price of batteries in general - his aim is to bring down the price of batteries suited for use in EVs, which means Li ion.

        Using different chemistry would not help him to achieve this goal. Convincing lots of people to buy Li ion batteries, even where another technology would be a better fit, would achieve this aim.

      • by Rei ( 128717 )

        Given the price of these packs, you'd have trouble making the argument that lead would be a better fit.

  • by Anonymous Coward on Sunday May 03, 2015 @08:03PM (#49608301)
    The Sun-vs-Electricity-Price-BNEF-Grid-Parity.jpg image incorrectly puts Australia's electricity rates at around 22c/kWh whereas it's closer to 28c/kWh in most places. This makes the Tesla storage tank even more attractive for them.
  • by endoboy ( 560088 ) on Sunday May 03, 2015 @08:07PM (#49608321)

    TFA makes much of the Tesla battery as a replacement for backup generators.... at 7kWh, it's equivalent to about 4 hours from a low end generator.

    Not anything that's going to replace my Honda and it's 20 gallons of gas any time soon.

    • by Waffle Iron ( 339739 ) on Sunday May 03, 2015 @08:23PM (#49608389)

      OTOH, in a real crisis, that might be the last 20 gallons of gas you get your hands on for a good while. The solar powered system refuels itself.

      • Re: (Score:3, Insightful)

        by endoboy ( 560088 )

        in the ice storm of 1998, we were without power for 10 days. Honda is my friend....

        Solar in the ice and snow strikes me as a dicey proposition

        • thats when we went out and bought one, tied it into our home and now when we lose power if its out for more than a few hours, our home is 75 percent powered (we didnt bother wiring in EVERYTHING, as we simply put in a sub panel for the essentials
      • It doesn't when your panels are under twelve inches snow and and a couple inches of ice, which is when I tend to lose power.

      • 20 Gallons is a LONG operating time. My generator uses around 1.6l of fuel per hour (3kW). 20 Gallons is 75l so 2 days of non stop usage. Admittedly in an end of the world scenario the panels will produce energy for longer I think you will have other concerns if getting more fuel has become that much of an issue.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      IF you put this in line with your generator, the generator doesn't need to run as often and doesn't have to ramp to follow load -- it can run at it's peak efficiency. Having this in your house with make that 20 gallons of gas go as far as 40 without it. The military has figured this out and are starting to battery buffer their generators at Forward Operating Bases -- fuel convoys are the most ran convoy, so reducing those by half really reduces attacks and the logistics train.

    • I won't be getting this Tesla battery, for a number of reasons, but I'd like a home battery system. I live in a condo and I haven't have a backup generator. Nowhere I'd be allowed to put it. A battery system though, that I could have.

      If I had my choice, I'd get a Generac whole house system but there are tradeoffs that you have to make when you want to live certain places.

  • Lead Acid (Score:5, Interesting)

    by Bob9113 ( 14996 ) on Sunday May 03, 2015 @08:16PM (#49608367) Homepage

    Lead acid batteries are still about half the price [wholesalesolar.com] per kWh (look near the bottom, at the 48v x 400Ah bank), and come with the same 10 year warranty. Cars care about weight, houses don't.

    The new thing here isn't battery storage of solar power, it's lithium-ion batteries instead of lead acid. The price performance for lithium-ion can't compete with lead acid yet, when weight isn't a factor.

    • by Dan Ost ( 415913 )

      So if this product has any amount of success we should expect to see cheaper competitors that use lead acid cells, right?

      That hardly seems like a bad thing.

    • And what happens to lithium-ion when you keep them topped off all the time? Even better than lead-acid is nickel–iron, but you'll need another house.

    • Re:Lead Acid (Score:4, Interesting)

      by mlts ( 1038732 ) on Sunday May 03, 2015 @09:33PM (#49608619)

      There is also battery life. Take NiFe batteries. They have less energy density than lead-acid... but properly watered, they have an extremely long lifespan.

      Yes, a rack of NiFe cells would take up a more room than Tesla's technology... but they will still be working and storing energy long after the current generation of lithium batteries have hit the landfills.

    • Re:Lead Acid (Score:5, Interesting)

      by aXis100 ( 690904 ) on Sunday May 03, 2015 @09:57PM (#49608683)

      Im not convinced. It's good that you've rated that pack at 50% depth of discharge (48V x 400Ah = 19kWh nominal, approx 10kWh @ 50% DoD), but typically lead acid packs will only get 1000 cycles at that rate. You typically have to go to a 30% DoD to get 10 years / 3000 cycles.

      Lithium can do greater depth of discharge for far more cycles. The overall lifetime costs of lithium per kWh were already starting to beat lead acid, and the new Tesla pack is even better.

    • Re:Lead Acid (Score:4, Interesting)

      by thegarbz ( 1787294 ) on Sunday May 03, 2015 @10:20PM (#49608757)

      Don't forget needing a spare ventilated room to dedicate to that much battery space. Houses do not care about weight but many do care about storage space and explosion hazards (though those exist with lithium too).

    • Lead acid batteries need to be vented, meaning they need to be stored inside with a special vent or outside, in which case you have a problem regulating temperature. And they have to be regularly maintained, which is not exactly straightforward enough for the general hoopleheads

  • by Thorfinn.au ( 1140205 ) on Sunday May 03, 2015 @08:37PM (#49608443)
    Most of Australia experiences Summer temperatures over the maximum operating listed in this specification, and for remote locations this maximum temperature is exceeded every day for weeks on end.
    This may be a design issue so a higher specification version could be issued of a physics issue and then it is no go for Aus.
    • Usable in Australia (Score:4, Informative)

      by slincolne ( 1111555 ) on Sunday May 03, 2015 @09:29PM (#49608589)
      The specifications you list cite a maximum temperature of 43 degrees Celsius.

      Now the maximum temperature for the majority of Australian households in summer rarely if ever reaches or exceeds that. There is a large amount of the continent where the temperature exceeds that - however its very sparsely populated (you are looking at the central deserts after all) and has minimal infrastructure anyway.

      For the majority of the population (i.e. major population centres on the coast) it's quite reasonable.

      • Melbourne a coastal city of 4 million and regular summer maximums of 45C and hotter inland. Adelaide is also on the southern coast of Australia (1.5 million) and has hotter and longer summers, so it gets a week of 45C+ days.
  • Why isn't the cost of solar panels included in any of the calculations about the Tesla's battery? What use is the battery if you don't have a way to charge it "for free"? Or am I missing something?

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