Watch Elon Musk unveil Tesla's Powerwall, a $3K battery for your home to 'change the world'

One thing a lot of people don’t realize is that with most residential grid tied solar systems, when grid power goes down so does your inverter. It can be the middle of a sunny day, but without a live grid connection all those panels on your roof don’t do a bit of good with a conventional solar installation. There is however a much less common hybrid grid tied system that incorporates a battery bank for backup purposes. This is an area where I could see these Tesla batteries making that type of solar installation a bit more practical than they are now.

1 Like

Very short life expectancy, not very controllable.
There are, however, companies who do make LPG-powered engines and people make conversion kits for Honda generators (which are reliable…) In Germany, a lot of people have natural gas powered 20kW VW generators in their basements which are also linked to the central heating.
Adding these batteries to such a system would make it more efficient and also greatly lengthen the generator service life.

1 Like

Once again, it is Edison vs Tesla. Let’s see whose battery can last for 100 years of daily charge/discharge cycles.

http://www.nickel-iron-battery.com/
http://www.zappworks.com/index.htm
http://ironedison.com/

2 Likes

This is interesting, but why is it that these sites all look like kooks?

Anyway, one of the downsides of nickel-iron batteries is probably weight, which is probably why they’re not great for laptops or cars. For home applications that shouldn’t matter. But Tesla has just made a huge investment in battery manufacturing technology, and they need to find a market for that extra capacity. I’d guess thats one of the main motivators for this move; they can make more batteries than their car sales justify, so they have extra capacity that can be monetized.

Without a multimillion dollar marketing budget and a slick website, they must be some of those “zero point energy” people!

So no Edison-cell powered aircraft. But Musk is selling his lithium cells for home power. So what if your batteries weigh several tons?

And how long is a battery supposed to last? Won’t the Tesla plant go out of business if everyone stops buying them?

That’s what I said.

I’m not saying that these Edison cells are the equivalent of perpetual motion hucksters (which is what I think you meant by zpe), I’m just suggesting that there must be some serious downsides for their use or otherwise they would have been more actively commercialized. Cost and weight seem to be the big problems - zapp charges two to three times the price of a Tesla battery, though to be fair they rate the battery for double the life of Tesla’s ten year warranty.

Again I’m not saying that Li batteries are the best solution for the home, I’m just saying why Musk thinks they’re the best solution largely because of the infrastructure he’s built, not because of some kind of built-in obsolescence.

And these are for sale and approved for use in a home where?

Except the reality in the US (and Europe) is that the well to do are reversing the flight of previous decades and moving back into the cities. Certainly my wife and I chose to live in Oakland to be in an urban environment, able to walk to all of our immediate needs, surrounded by cafes and people, rather than living in some hidden woodland homestead waiting for the zombies.

2 Likes

http://fuelcellstore.com/fuel-cell-stacks

Edit: Other amenities like compressors and storage tanks are at the same sites in different menu hierarchies.

As of approval, for a home-scale system a don’t-ask-don’t-tell method should work well enough.

Which may as well make the cities suck more instead of less…

Urban environment has a few advantages that make it easier to suck it up. But the peace and lack of too-many-of-other-people is just not there.

[quote=“JohnS, post:41, topic:56680”]
I could see these Tesla batteries making that type of solar installation a bit more practical than they are now.
[/quote]Indeed, I think there are two basic use cases for the Tesla Powerwall, which correspond to the two models offered:

The $3000, 7kW/hr model is optimized for daily charge-discharge cycles. This model is intended for off-gridders, who need to store power from intermittent sources (solar panels, wind turbines, etc.)

The $3500, 10kWh model is optimized for backup use, with the battery kept constantly topped up and only discharged during power failures. This model is aimed at people who already have (or are considering) a grid-tied solar-power system. With the Tesla battery, a grid-tied system becomes a grid-free solar backup system when the grid goes down.

But really, while everybody’s scratching their heads over the Powerwall, the really significant things in this announcement, IMHO, are:

(1) The Powerpack, the 100 kw/hr industrial version that provides infinitely-scalable utility-grade storage for ~$250 per kW/hr. For large businesses who get off-peak discounted power or pay peak-demand charges, this is a real game-changer.

(2) Musk’s remark that the Gigafactory is better thought of as a product than as a factory - essentially, Tesla intends to sell not just batteries but entire battery factories — giant, immobile machines that take in raw materials and spit out Li-Ion batteries.

I’m also pleased to see his continuing commitment to open-sourcing all the tech and making the patents freely available — he actually wants to encourage competition; a rare trait in publicly-traded companies.

2 Likes

16.41TW = 16 410 GW which is very close to 15 000 GW, so that’s probably the value to use.

The NiFe battery does have some disadvantages. My school used them for teaching basic electrical science, and I think the main disadvantage is that with the technology available up till the 70s, it was hard to know when they were fully charged; also the charge/discharge efficiency isn’t very good and the peak current is poor - a safety factor in schools where you can’t use Pb/PBO2 batteries because of their ability to melt wires and even screwdrivers. It is also always going to be a lot heavier than a lithium battery due to the elements involved, so is unlikely to make a return for traction.

Given limits on world supplies of nickel, focussing on light metal batteries should be a no brainer. (The world has a lot of nickel but unfortunately it is rather inaccessible due to the thousands of km of molten rock between us and it.)

3 Likes

I’d say that this factor certainly adds to the learning experience, but both I and my high school EE teacher are rather hardcore in this regard…

Combined heat and power systems are quite popular amongst a certain kind of rural German - the ones I’ve seen were wood pellet or diesel, though. Biogas seems to be becoming a big thing in Niedersachsen though so there probably would be a market for a gas version - allow farmers to eat their own dog food.

Iridium is extremely expensive, so has the same problem as platinum. Ruthenium is slightly better, but still far too rare and expensive to scale. If you don’t take cost into account, a lot of this stuff is easy. Back in the '80s, they made a direct solar water splitting device with >10% energy efficiency. If that would scale at a reasonable price, it could solve all our energy problems, unfortunately, it was an indium based PV cell with a platinum catalyst.

I actually used to work in a lab working on nanostructured nickel oxide water splitting. It is a very promising technology, and I think we should be investing a lot more in tech like that, but it’s not fully there yet by any means. Unfortunately, I don’t have access to the full article you linked to, and they don’t have any relevant figures in the article you linked, which came out since I left that field, so I can’t say if it’s a real breakthrough or just more hype in a press release, but statistically, I’d say the odds heavily favor the latter.

1 Like

Not as abundant as iron, but way way way more common than some of the other elements being tossed around here (like ruthenium) … lithium isn’t really all that abundant either, by the way. You can allegedly get it from seawater, like everything else, but at what cost?

And while lithium battery technology is far and away better than the NiMH batteries of twenty years ago, let’s see one of Musk’s cells after 30,000 deep discharge/charge cycles. The lithium battery in my iPhone has been replaced already, in less than one decade.

1 Like

This is all relative to what you like.
The thought of living in a suburban or rural environment makes me break out in hives.
I can’t stand the former in any way, and the latter gives me the creeps except in special instances like on the way to a park. That I like. Today my wife and I spent a few hours hiking out east of here in one of the state parks. Spending time in Yosemite or Big Sur or whatever is extremely enjoyable for vacation.
Rural American towns - not so much. Not at all.

I did nor manage to find the fulltext of the article but the Nature abstract and figures are here:
http://www.nature.com/ncomms/2014/140822/ncomms5695/full/ncomms5695.html
A better version of the popular blurb is here:

Hope it can tell a little more…

Just managed to stumble over something when researching fission products. Ruthenium is plentiful in spent fuel. There are even some texts about using reprocessing rafinates as ruthenium and palladium sources. Which I’d consider to be a good idea.

Yeah, he’s no Steve Ballmer.