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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."
"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."
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.
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
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.
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:
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
since AC is the biggest consumer of residential power
This is a huge (and for the vast majority of the world: incorrect) assumption. Down here at 40N the peak winter solar incidence is 1 third of the summer peak (10 MJ/m/day cf. about 30 in June / July) but with decently built houses that are designed for the climate there is no need for cooling during the summer months.
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
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.
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.
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.
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.
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...)
But what was the humidity level? 40C at 30%RH is much different than 40C 90%RH.
Australia is exceptionally dry compared to places that require Air Conditioning. Although it isn't a desert, so it's not completely arid.
http://www.currentresults.com/Weather/Australia/Cities/humidity-annual-average.php
vs.
http://www.currentresults.com/Weather/Canada/Cities/humidity-annual-average.php
(The numbers might look close, but please consider that in the winter Canadians run a humidifier due to exceptionally dry winters. In the summer, 95% RH is not unusual).
In fact, where I live, employers are not allowed to use temperature as a measure for when to tell employees they can go home due to heat. They have to use a "humidex" measure, which estimates the effect on the human body of heat when sweating simply does not work as a cooling measure.
http://en.wikipedia.org/wiki/Humidex
Be assured, we laugh at people from Arizona spending summertime in Canada who are dying from heatstroke because they didn't understand that 45 C in the desert is equivalent in exhaustion and heat stroke to a typical 30 C muggy horrid summer's day here.
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.
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?
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?
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.