
Tesla Motors Announces a New Home Battery - jnaveen
http://offgridquest.com/news/tesla-motors-announces-a-new-home-batter
======
brudgers
_So, where does lithium come from? It comes from the Earth, of course, but it
doesn 't require strip mining or blowing the tops off mountains like other
resources do...most often, lithium is found in briny underground ponds. The
liquid is pumped out and left to dry in the sun._

TANSTAAFL

[https://duckduckgo.com/?q=lithium+pond+photos&iax=1&ia=image...](https://duckduckgo.com/?q=lithium+pond+photos&iax=1&ia=images&iai=http%3A%2F%2Fwww.sciencephoto.com%2Fimage%2F438264%2Flarge%2FC0115790-Lithium_evaporation_pond-
SPL.jpg)

Mining is mining. There isn't a "green" form. Tearing holes in the earth is
not the worst ecological damage or the great health risk. The big problem is
the water...and it will run downhill from the Andes and wherever else Lithium
is mined and into the Ocean.

The house off the grid is built on industrial infrastructure.

~~~
headShrinker
Also many municipalities don't allow battery 'grid-tie' with the option of
'off the grid' living. For example, Connecticut has laws which don't allow
houses to have batteries that would allow a house to be self sustaining and
have a connection to the grid. This is because if you have batteries which
cause a back flow during a power outage to the power station, an electrical
worker could get shocked down the road.

The fact that lithium batteries aren't the greenest combined with the fact
that you can't even live 'off the grid' in a grid tied system is a big uphill
for these batteries.

~~~
fche
A properly wired transfer switch fully cures that risk.

~~~
danielweber
And even though the solution is right there, power line worker remains the
ninth deadliest job in America.

[http://www.businessinsider.com/most-dangerous-jobs-in-
americ...](http://www.businessinsider.com/most-dangerous-jobs-in-
america-2014-12#9-electrical-power-line-installers-and-repairers-2)

~~~
maxerickson
On trip through Minnesota, I watched a helicopter ferry guys up onto the
towers to work (they dangled from the helicopter and then transferred over to
the tower: [http://www.capx2020.com/](http://www.capx2020.com/) ). They were
building the type of infrastructure the news says America doesn't know how to
build anymore.

I wonder if energized lines are the big problem.

~~~
tlrobinson
Workers can safely work on _live_ high voltage lines, if they're wearing a
Faraday cage "hot suit" and not grounded:
[http://youtu.be/LIjC7DjoVe8](http://youtu.be/LIjC7DjoVe8)

~~~
lutorm
That video is awesome. I've seen a version with much better quality that
really gets my acrophobia going... ;-)

------
jacquesm
It's very hard to beat lead-acid on:

\- $/Wh

\- number of cycles

\- ability to be recycled at eol

\- loss of capacity over the lifetime of the battery (or beyond!)

\- safety

It is easy to beat on

\- power density

\- weight

\- maintenance

\- mechanical stability (especially for fluid based cells)

\- installation cost (lead/acid requires a sealed enclosure venting to the
outside to get rid of free oxygen and hydrogen)

The same batteries that work well for automotive applications will not do that
well when you're building a storage cell for a house.

Lithium-ion does not have a whole lot of edge over lead-acid deep cycle gel
cells when it comes to stationary applications.

The biggest issue with Lead-acid is that if you don't water them (if you use
fluid based cells rather than gel based cells) that sulfur bridges can grow
between the plates causing a cell to be shorted out. Gel based cells don't
have that problem and are common in deep discharge setups.

~~~
IgorPartola
Energy density is a big one. To store 5 kW * 24 hours (barely enough to power
my house's essentials), I would need 286 of these
([http://www.amazon.com/VMAX857-Battery-Performance-
minnkota-t...](http://www.amazon.com/VMAX857-Battery-Performance-minnkota-
trolling/dp/B008974VFG/ref=sr_1_1?ie=UTF8&qid=1424184394&sr=8-1&keywords=deep+cycle+marine+battery)).
They are not small. Also, that would cost me nearly $32,000 in just batteries.

My ideal setup for this would be something like 20 kW * 7 days. That would
fill my basement pretty easily.

~~~
jacquesm
That's a _very_ expensive battery for the given capacity. If you want to be
efficient check out the gel batteries used to power golf carts and forklifts.
You'll need 24 2V cells if you want to do this efficiently both from a cost
perspective as well as to reduce line losses between batteries and inverters.
(24 and 12V are really not adequate for larger power installations).

~~~
IgorPartola
Such as these? [http://www.batterystuff.com/batteries/golf-cart-
products/](http://www.batterystuff.com/batteries/golf-cart-products/)

I don't really see orders of magnitude jumps in power/$. Or am I looking for
the wrong thing?

~~~
jacquesm
No, more like these:

[http://pics.camarades.com/v/jacques/renewables/batteries/IM0...](http://pics.camarades.com/v/jacques/renewables/batteries/IM000329.JPG.html)

Sold in bulk. That's a 48KWh bank and it cost about $US 5K

~~~
IgorPartola
This is roughly 2.5 times cheaper than the marine battery I found first,
definitely not orders of magnitude.

This is $5k for 2 kW * 24 hours. So 3 of these at $15k total would roughly
replace my $700 generator + $10 worth of gasoline for emergency situations.

To truly run my house where it would be adequate at 20 kW or 24 hours or so,
I'd need 10 of these at $50k. To run my house of for a week (where I live, the
last major power outage lasted three weeks), I'd need $350k. For that amount
of money, I can just buy a very nice house in Florida and go down there when
the power goes out.

Now, if I go top of the line, I can get a 22kW generator
([http://www.homedepot.com/p/Generac-22-000-Watt-Air-Cooled-
Au...](http://www.homedepot.com/p/Generac-22-000-Watt-Air-Cooled-Automatic-
Standby-Generator-with-200-Amp-SE-Rated-Transfer-
Switch-6551/205398231?N=5yc1vZbx9s)) for $4,700 + gasoline at $2.30/gallon
where I live. This will not even require me to go out and start the thing as
it kicks on automatically, much like a battery backup does.

Battery powered houses just don't make sense cost-wise, and at this price
disparity it's not a question of spending a little more: $350,000 vs $4,700.
That's two orders of magnitude. It's not the clean option, but given that it's
standby power, I'd rather see us invest in more efficient power plants
(nuclear and wind) than home batteries.

~~~
jacquesm
I think you're more than a bit power hungry. My house consumed < 5 KWh _max_
per day, so even running to 50% discharge that bank would power the house for
up to 5 days.

It's much easier to save on consumption than to create capacity, especially
stored capacity. You don't really realize just how much energy goes into AC,
heating, washing and so on until you've lived off the grid for a bit. And then
you'll quickly learn how to conserve energy. I'm currently living in an on-
grid house, the old habits die hard, my computers are probably the biggest
consumers here.

Anyway, if 22KW is your power budget then don't bother going off-grid without
a generator.

Battery powered houses make perfect sense if you're able to conserve power, if
you can't then of course it does not make sense.

~~~
IgorPartola
That I suppose is the line for me. I am unwilling to go to a point where I
cannot use my washer/dryer, dishwasher, AC, etc. I believe the majority of the
developed world is with me on this, though of course there is a minority that
have other priorities.

------
gizmo
It looks like Elon wants to ramp up production in the new Gigafactory right
away, and create home batteries from the excess capacity. A Gigafactory
running at full capacity should bring the cost of lithium ion batteries way
down. Electric cars haven't hit the mainstream yet, so he has to do
_something_ with the excess capacity, and this looks pretty straightforward.

So even if he sells these batteries at the break even point, he'll still get
much closer to an economically viable Model 3, because the battery is such an
expensive part in an electric car and this will bring the price of batteries
down.

(I'm not sure if my reasoning makes sense though, because the Gigafactory
isn't anywhere near finished yet, and according to wikipedia it won't hit full
capacity until 2020.)

~~~
bsilvereagle
Home batteries have arguably fewer cycle times than a battery in a Tesla. By
selling these, Tesla is essentially selling beta models to figure out kinks in
the factory, in the batteries, etc, before putting them into their mainstream
vehicles that have to suffer huge temperature gradients, lots of recharge
cycles, etc.

------
quarterwave
I have home back-up power based on an inverter charging a lead-acid battery
(located in a sheltered area outside the home), which costs about $100/kWh.
Usage is about 1-2 hours discharge per day. No matter how well serviced, I've
found these batteries don't last beyond four years. Hence I'd pay even
$400/kWh for a well-engineered deep-cycle battery that is safe, maintenance-
free, and will last at least 10 years. Excluding balance of system, even.

~~~
jacquesm
> No matter how well serviced, I've found these batteries don't last beyond
> four years.

Wow, that's _really_ short, especially with such a shallow discharge pattern.

~~~
msandford
Not necessarily! We don't know how deep the battery is being discharged. But
we can make a guess. 4 * 365 = 1400 cycles.

[http://www.mpoweruk.com/images/dod.gif](http://www.mpoweruk.com/images/dod.gif)

According to that chart (which is an approximation of course) 1400 cycles
corresponds to about a 40% depth of discharge. Which isn't terribly shallow.

The other variable is the discharge rate, and the higher it is relative to
battery capacity the worse the efficiency and also the propensity to fail
early. A lot of times doubling the pack size can extend the pack life by more
than two because the increased efficiency (the internal resistance is lower)
reduces the depth of discharge by more than half.

[http://batteryuniversity.com/_img/content/crate1.jpg](http://batteryuniversity.com/_img/content/crate1.jpg)

Of course it feels totally ridiculous to only use 20% of the nameplate
capacity of the system, and much worse than using 40% which you can sort-of
rationalize as "half" but if it decreases your dollars per joule, it might be
worth it.

EDIT:

I should also mention that if you're constantly charging and discharging and
you don't mind a little energy loss you should look at nickel-iron batteries.
They're not terribly efficient nor are they cheap in absolute terms but
they're basically bulletproof.

[http://en.wikipedia.org/wiki/Nickel%E2%80%93iron_battery](http://en.wikipedia.org/wiki/Nickel%E2%80%93iron_battery)

[http://ironedison.com/](http://ironedison.com/)

~~~
glabifrons
I've wondered for years why people always gravitate towards Li-Ion cells when
talking about a home storage battery. Li-Ion's advantages are far, far less
important for a dwelling. Weight doesn't matter... you won't be moving them.
Size doesn't matter nearly as much as it does in a vehicle... losing a few
inches off an entire wall in a garage won't really be an issue for most
people. Edison cells are incredibly durable and much, much more
environmentally friendly than any other battery tech I know of. The lifespan
is nothing short of incredible too... you won't need to change them out.

Thank you very much for the 2nd link. I was unaware any company was still
manufacturing them. The last time I looked, the last company I could find that
made them stopped a few years prior. I'm glad someone is making them
still/again and marketing for an appropriate use.

The one odd thing is the price... for something as low-tech (relatively
speaking) as an Edison cell, I'd expect them to be much cheaper. Must be the
lack of competition.

~~~
jacquesm
They may _seem_ to be low tech but the electrodes are works of art and
manufacturing them is a lot more expensive than a lead-acid battery of
comparable capacity. They charge slower too, but they'll stand up to abuse
better than every other rechargeable battery tech. I looked at them for a long
time before settling on regular lead-acid, cost and finding an inverter that
would charge these properly were the major factors.

------
PanMan
What would be the advantage of these LiPo batteries over traditional lead-
based batteries? In car's, I understand weight (and volume) are really
important, but for stationary usage these seem way more expensive / Wh stored?

~~~
jerf
I'm also curious about their lifetime. My laptop batteries are pretty weak
after three or four years. It's much easier to justify $thousands as a one-
time purchase than $thousands/year. For many of its applications, this is
going to have to beat a generator. Which, come to think of it, probably means
that if they're pitching this as a way off the grid it is precisely because it
won't be even remotely competitive with a generator.

~~~
higherpurpose
You charge your laptop everyday. So it depends on how often you recharge them,
which means it will depend on how big of a battery you'll buy. If you buy a
100 KWh battery (probably around $10,000-$15,000), I think that should last
most Americans at least several nights to a week? So it might approach 10
years before it starts degrading, and then probably a few more years of
charging it every day. I assume's Tesla's batteries will be relatively high-
quality as well.

~~~
lsaferite
Isn't the idea that you keep it topped of and use it when grid power is
expensive or missing? That usage pattern would involve multiple charge cycles,
perhaps even 365 in a year. I guess it would actually follow the Tesla
charging patterns fairly close as well. What is the estimated lifetime of a
Tesla's battery?

~~~
vidarh
If the battery has sufficient excess capacity, you can split it into multiple
banks of smaller batteries, and cycle which ones you charge and which ones you
use. Add a small computer and you can use whatever logic gives you optimal
charging/discharge patterns to optimise for lifetime.

------
phreeza
The 'living off the grid' angle is a red herring. The main application of this
would be solving the peak load problem, ie smoothing out the load on power
stations throughout the day. It is not clear to me how a LiPo batter is better
suited for this than other battery types though, especially since weight is
not a concern for a stationary battery in your home.

~~~
alex-g
I wonder if this even needs to be something in the home. Wouldn't it also make
sense to install these things, in bulk, in a place where they could service
several homes? Say, at the block level. If it is part of power distribution
infrastructure as opposed to a consumer product, then that simplifies some of
the safety and maintenance issues; concerns like weight or volume are even
less important if they are housed in a dedicated structure.

~~~
phreeza
This is being done. Power companies have shipping containers full of batteries
hooked up to their grids. I have read better stories but the first thing I
found googling just now is this [http://www.abc.net.au/news/2015-01-07/ausnet-
trialling-new-s...](http://www.abc.net.au/news/2015-01-07/ausnet-trialling-
new-system-to-curb-power-outages-on-hot-days/6004454)

~~~
sehugg
That's still a pilot program, though. The Wikipedia article has a good summary
of various tech and installed systems:
[http://en.wikipedia.org/wiki/Grid_energy_storage#Batteries](http://en.wikipedia.org/wiki/Grid_energy_storage#Batteries)

------
Already__Taken
Can someone explain to me why being able to build off the electrical grid is
worth all this effort since you're still going to need running water, sewage,
bins collecting, broadband and a number of other things?

~~~
datashovel
From the research I've done on solar power systems (for powering homes) the
market does not have an obvious pre-packaged solution that is made for storage
of excess capacity generated by your solar panels.

One commonly suggested (and substantially cheaper) option is to just set
things up so you don't have local battery storage and just redirect all excess
power back to the utility company.

The problem with that has already been mentioned. You're giving power back to
the utility company at a fraction of what you purchase electricity for.

But beyond that, as power requirements in appliances / computers / electronic
gadgets continues to decrease, and efficiency and capacity of alternative
energy solutions continues to increase, there will likely come a time (in the
not-too-distant-future) when there will [at least in theory] no longer be a
need for utility companies.

In fact, from varied sources online I've gotten the impression that many
countries (besides US) have substantially reduced power requirements per
household where even today it's feasible (for those with sufficient roof
space) to move all of their power usage off grid, and rely strictly on power
generated by solar.

~~~
tomp
> The problem with that has already been mentioned. You're giving power back
> to the utility company at a fraction of what you purchase electricity for.

That's not a problem, that's how the markets work. When electricity is
abundant (i.e. sun is shining, wind is blowing), it's cheap; when it's in
demand (in the evening, after the sun and wind stop but people want to cook
and watch TV), it's expensive.

The problem with energy storage isn't just a home-problem, it's a network-wide
issue. AFAIK, current batteries aren't really able to solve this issue, in the
long-term (i.e. considering the lifetime and replacement of the battery).

------
LeonM
I've always been wondering why there have never been affordable local power
storage solutions on the market.

I'd love to have a battery like this to store excess power from solar panels.
Returning power to the grid is a waste in both efficiency and money (you just
make the power company richer).

Unless you live in Germany (where there are laws forcing power companies to
buy excess energy back against peak price), a battery should be the way to go.

~~~
repsilat
I guess the big questions are,

\- How do battery charge/store/discharge efficiencies compare to transmission
losses?

\- How do capital investments to support returning power to the grid compare
to the cost of batteries?

One thing I'm fairly confident of is that just having batteries (without solar
panels) to do peak-flattening temporal "arbitrage" can't make economic sense.
If it did, power companies would do it themselves and keep the profit.

~~~
pbowyer
> One thing I'm fairly confident of is that just having batteries (without
> solar panels) to do peak-flattening temporal "arbitrage" can't make economic
> sense. If it did, power companies would do it themselves and keep the
> profit.

They're trialling that right now in the UK:
[http://www.itv.com/news/anglia/2014-12-15/power-boost-as-
big...](http://www.itv.com/news/anglia/2014-12-15/power-boost-as-biggest-
battery-in-europe-is-tried-out/) [http://www.edie.net/news/6/Smarter-Network-
Storage-Energy-ba...](http://www.edie.net/news/6/Smarter-Network-Storage-
Energy-battery-project-Leighton-Buzzard/)

------
CapitalistCartr
I'd love to have a self-contained electrical system for my house. I'd
preferentially wire my home with a DC grid alongside the AC, but there's no
standard. Do I run 120v, 240v, 5v, 12v? Which interface do I use? Barrel
connectors, USB, cigarette lighter? If we have a large-scale movement to
household DC, we'd have these things hammered out without me rewiring every
appliance.

If these obstacles were overcome, almost everything in my house could run on
DC. Most stuff either converts to DC internally, or doesn't care.

~~~
fredkbloggs
There are standards, many of them, just as there are many different standards
for AC power worldwide. Your DC system design will be governed by practical
technical considerations in concert with economics. The physics of low-voltage
systems are such that they are viable only when current is low; otherwise, a
5V or even 12V system will require prohibitively expensive heavy-gauge wire in
order to provide the proper voltage at the point of use. So modern DC systems
are typically all 48V or even higher now (people are building solar systems
with system voltages of 600VDC!). That does not mean you need to run those
higher voltages within your home, but from a practical perspective you
probably want either 24V or 48V unless your house and/or current needs are
very small. To figure this out, you need to consider the following:

\- What devices do you need to supply? Often this is the true governing factor
although switching regulators are very efficient and inexpensive up to a few
amps. \- How much current do you need to supply to a particular location (this
depends on the power consumption of what you're running)? \- What is the
distance from the panel to the point of use? The longer the distance, the
greater the voltage drop across a wire of a given size (and the higher the
cost of larger wire).

As for connectors, there are only a couple of sensible answers. USB is fine
for 5V/1A needs, but you're not going to want to run a bunch of 5V wiring
separately from the higher-voltage wiring you're going to need anyway. The
proper approach here is something like [http://www.powerwerx.com/adapter-
cables/usbbuddy-powerpole-1...](http://www.powerwerx.com/adapter-
cables/usbbuddy-powerpole-12v-usb-5v-device-charger.html), which will happily
work in either a 12V or 24V nominal system. You can of course make other power
supplies from all-in-one ICs like [http://www.mouser.com/ProductDetail/RECOM-
Power/R-78W90-05/?...](http://www.mouser.com/ProductDetail/RECOM-
Power/R-78W90-05/?qs=sGAEpiMZZMsc0tfZmXiUnUkNRh%2feR2rThZf2%252bPpU02Tot4ByAEAirQ%3d%3d)
and a small project box; larger currents and other voltages are available too,
of course. These make good replacements for wall warts.

But you don't want to be wiring any of that in your house; instead, you want
to use Anderson Powerpoles in a single-voltage (probably 24V or 48V) system.
They are properly rated for DC use at these voltages and plenty of current (up
to 350A if you need it, which you won't). They can be installed in blocks of 4
2-blade connectors in standard wall boxes, with neat, professional plates.
They can be easily crimped onto appropriate-gauge wire by amateurs. They are
code-compatible and safe, unlike the dangerous practice of using receptacles
designed for 120VAC or some other existing local/regional standard. They
provide a reliable connection and reliable disconnection, and if crimped
properly they will not fray, crack, or loosen within a very large number of
connect/disconnect cycles. The other low-voltage DC "standard" that is
popular, the barrel-type "cigarette lighter" connector, provides only 7A at
12V, is bulky, and does not offer a reliable connection. While it is popular
in automotive applications, more serious users of DC power -- the Powerpole is
very popular among amateur radio enthusiasts -- avoid the barrel type
connectors for these reasons.

The only real decision to make is whether to use 24V or 48V, which will depend
primarily on the questions I noted above. Higher voltages are certainly
possible, but watch out! Switches rated for higher DC voltages (especially at
currents much more than 1 or 2A) are hard to find and expensive. Your standard
"AC quiet switch" that you can buy for $2 at the local hardware store is rated
for 125V AC ONLY. It is not safe to use with any DC system, although in
practice it's probably acceptable for 12V systems at a hundred milliamps or
so. For more practical applications, you will need to be sure that your
equipment is equipped with proper switches, or no switches at all; you will
also need to make sure that any hard-wired DC circuits (such as for lighting)
are properly switched. Where you have flexibility in the voltage accepted by
your equipment, you will need to trade off the higher cost of switches and
other passive components at higher voltages against the higher cost (or
voltage drop) associated with wiring at lower voltages. You will quickly learn
to read spec sheets and rating stamps carefully when you work with DC.

The last thing I'll mention is that you may not really want to do this. At my
location, there are often several months with extremely limited power; even
the inverter's 25W base consumption dictates that it be on an hour a day or
less if at all possible. For that reason, anything I have that needs smallish
amounts of power continuously (such as a freezer, reading lamp, phone charger,
etc.) gets DC. But in general, it's simply more convenient to use off-the-
shelf devices. I can and do make my own power supplies, but I don't really
want to go re-power my laser printer or table saw (which by the way has an AC-
only induction motor in it). For higher-power devices, off-the-shelf is the
way to go; it's much cheaper and the inverter's overhead is amortized over a
lot of consumption anyway. If you have a larger system that can easily supply
100W or more on an indefinite basis, you probably don't need to bother much
with DC; it'll be easier to just leave the inverter running all the time. A
DC-powered well pump or freezer might be worthwhile, but I wouldn't go
converting anything else. Most people are putting in enormous (to me) solar
systems now; 10kW is common. With a system that large, you'll probably be fine
even if it's overcast. For reference, I have 700 watts, and with endless
stretches of 6-hour overcast days in winter, DC is the only way to fly. But
your needs are likely to be very different indeed, especially if you have (as
we're discussing here) adequate storage. The days of custom-wired 12VDC off-
grid living are basically over unless your budget is extremely limited.

~~~
CapitalistCartr
My budget isn't limited, so that's not a problem. I'm an electrician, so this
would be a project for fun. But I know if residential DC became a thing, this
would be so easy. I think we'd all be better off with residential DC and solar
panels.

------
PhantomGremlin
Sure, Musk makes it sound sexy, but do we really need to use Lithium in a
stationary application? I'd probably be happier with a battery that weighs
twice as much but costs half as much. Those might not be the exact tradeoffs,
but that's the general idea.

However, I don't know much about the details of battery technology, so I could
be completely wrong. If traditional technologies such as lead-acid were up to
the task, then someone would have already made a big business out of using
them. Does that make sense?

~~~
offgridquest
Lithium batteries are not only lighter, but smaller. The typical home today to
go off grid in the U.S. is a tiny house or a motorhome. The reason is, it's
very cost prohibitive for the amount of power you need. Batteries are the most
expensive part of that equation. If you live in a 3000 sq foot house and run a
$250 per month electric bill, it might take 50 $130 golf cart batteries to
power your house for a day or two, and you replace them every 4-5 years. Or
you could go with Iron Edison batteries that should last a lifetime. They are
equivalent to about 4 golf cart batteries, and the only requirement is to re-
fill them with liquid. They cost about $4,000 each, and are yet still very
heavy. The lithium batteries will take up about 1/5 the size and even less
weight, and should last much longer than the golf cart batteries, but not as
long as the Iron Edison. But space and weight requirements down so much will
bring down costs with overseas shipping and trucking bills to a minimum
compared with the alternatives. Think what great success in small batteries
has done for cell phones. Not that your home needs to be mobile, but I see
cars with solar panels and homes with solar shingles... both always
charging.... as a great use of the sun as an energy source.

~~~
yourapostasy
Is that $4000 figure for the 12V battery made out of 800Ah 1.2V cells, rated
at "400Ah @ 5hr, 450Ah @ 20hr" shown on their web site for $3880? I've always
wondered why more fixed site solar PV systems do not use iron nickel
technology; it it is initial cost, I wonder what makes this technology so
expensive.

Some day I want to look into the feasibility/advisability of a continuous
automatic feed of distilled water to keep iron nickel batteries constantly
topped off, and a hydrogen outgas capture mechanism (preferably passive) which
takes that output of the iron nickel batteries and feeds it as the input into
a hydrogen cell.

------
PinguTS
The question is: Will it be new battery just for homes or will it be a
recycled/repurposed battery from 'old' Teslas?

It think it will be the later one. Elon is just thinking ahead. There is
nothing really new in this story. Everything is just made up. It is quite
accepted within the industry, that when the car battery has a capacity of less
than 70% to 80% it needs to be replaced. But what should the car company, in
this case Tesla, should do with battery? Of course, it will be re-packaged and
as such repurposed for other use. What other use case is there? The other use
case is Solar, especially as his friend runs a Solar company. What in
incident.

------
unwind
Could someone please fix the truncated title? My editorial advice would be to
just cut from the semicolon.

------
joosters
Have Tesla solved any of the problems that have prevented people from selling
large storage batteries in the past?

A big issue is that you don't get that many charge cycles, especially with
lithium-based batteries. So, filling up the battery with solar power during
the day, then running your house from the battery in the evening, will soon
fall to pieces if the battery doesn't last a decent number of years.

------
meesterdude
Awesome! and great news for the renewables.

Right now, if there's a storm or what have you you can lose your heat, your
power, your water - everything. Its a bit like the mainfraime/terminal days -
everything is centralized, and represent single points of failure for the
citizens it serves.

But with energy you create yourself, and things like water recycling or indoor
farms, we could go fairly far in self-sustaining units. And instead of the
grid, there could be local community sharing so if your power/water goes out
you can pull from a local grid. It doesn't need to be in every home, but
something more distributed means more resiliency in the system overall, and
thats handy in a lot of scenarios.

All that's a ways away though - but making the energy storage better / cheaper
is an important step.

But I'm curious of the environmental factors in battery production / lifetime
/ recycling, can anyone comment on the impact these batteries represent?

------
m-i-l
In addition to doing things like storing any excess solar power you might
have, it could also be used to charge up at night on off-peak rates ("Economy
7" in the UK) and release during the day to reduce your peak rate electricity
consumption - whether it would be financially worthwhile to do so would depend
on a number of factors.

------
phkahler
When will homes be built with sensible electricity distribution? So often they
put the breaker panel in the basement. I want a small utility room or closet
where I can install inverters or this battery. I want to be able to run 220V
to my stove, laundry, garage (car charging), battery storage, and AC
relatively easily - none of these is in the basement (except the laundry in
some home I've lived in). Also, if a basement floods, how is one supposed to
go down there to access the panel without risk? And it's darkest down there
too. It just seems to be the stupidest place to put it. What's up with that?

~~~
dpark
What's up is that most people don't want a big breaker panel in a room they
spend time in. It's ugly.

Sticking the panel in a closet doesn't work, because it generally violates
codes twice, once for the fact that all the clothes/random junk in the closet
blocks access to the panel, and a second time for the fact that even empty,
most closets don't provide sufficient clearance all around the panel to meet
code requirements.

If I were building a new house, I'd consider putting the panel on the main
floor and just hanging a big painting to hide it (which still violates code,
but it's pretty trivial to take down a painting).

------
ChuckMcM
Seems like just yesterday [1] I was saying they could do this if they wanted
to. :-)

The first challenge is to make the operational cost of a solar + battery
system less than the cost of buying your power straight from the grid. The
second is to include capital costs in that calculation and still come out at
break even or ahead.

[1]
[https://news.ycombinator.com/item?id=9055177](https://news.ycombinator.com/item?id=9055177)

------
fidotron
It will be interesting to see the market reaction to this regarding the value
of electricity generation companies.

Governments that lean too heavily on taxes or state run monopolies for energy
generation should also be concerned. There are places that tax generation from
sources like the wind (for example, Nova Scotia), so I wouldn't be surprised
if we see solar tax appear.

~~~
lsaferite
Thinking about it, why wouldn't utilities jump at this and make it a standard
part of every install? It would allow them to lower the demand-based
generation due to every house having a local buffer of storage. They could
easily monitor the levels on all the packs in a sector and know ahead of time
when they are going to need more capacity which they can fill with better
generators like gas turbine or nuclear.

------
Shivetya
I disagree that the long term storage stationary storage is extraordinary, at
least from the individual home standpoint, it does have great utility
application (for windfarms/hydro/etc) and likely would help some businesses
offset day time surcharges by charging storage at night.

Still for home use, I would prefer a large lithium pack to be outside my home.

------
Sir_Substance
This still doesn't solve the essential problem with these batteries:

They're about $20k each, and they only last about 4 years.

~~~
dm2
The Model S 85kW battery pack is estimated to cost $12,000 and is estimated to
last 10+ years.

The SolarCity Battery field-test uses 10kW Tesla batteries and is leased for
$1,500 upfront and $15 per month. So, if the batteries degrade, it's
Tesla/SolarCities responsibility to fix or replace them.

The Gigafactory will likely reduce costs significantly.

[http://www.theverge.com/2015/2/13/8033691/why-teslas-
battery...](http://www.theverge.com/2015/2/13/8033691/why-teslas-battery-for-
your-home-should-terrify-utilities)

Essential problem solved?

~~~
Sir_Substance
The list price for that pack according to these people is 44k.

[http://www.greencarreports.com/news/1096801_tesla-model-s-
ba...](http://www.greencarreports.com/news/1096801_tesla-model-s-battery-life-
how-much-range-loss-for-electric-car-over-time)

It looks like you drank the tesla dealers coolaid:

[http://my.teslamotors.com/forum/forums/tesla-model-s-85kw-
ba...](http://my.teslamotors.com/forum/forums/tesla-model-s-85kw-battery-
replacement-cost)

Bad luck.

~~~
dm2
This clearly states that the cost for a replacement 85kW battery will be
$12,000.

[http://www.teslamotors.com/blog/2013-model-s-price-
increase](http://www.teslamotors.com/blog/2013-model-s-price-increase)

"We have received many requests for a Battery Replacement Option. We are happy
to now offer this option for all three battery variants. This option will
provide you a new battery anytime after the end of the eighth year at a fixed
price. Prices are as follows: $8,000 for the 40 kWh battery, $10,000 for the
60 kWh battery, and $12,000 for the 85 kWh battery. You will be able to
purchase this additional option through your MyTesla page in the near future."

I can't imagine that they would raise the price by 4 times. Where is the
source for the $44,000 listed on the article you mentioned?

If there are 7,000 18650 batteries in a Tesla S battery pack and it's
reasonable to assume that Tesla can produce (Gigafactory) these for $1 then
the $12,000 seems perfectly reasonable. The current estimate for the cost of
18650s for Tesla is less than $2.

It's already been stated that the cost of a battery pack is less than a
quarter the cost of the car, so the $44,000 is nothing but false.
[http://www.technologyreview.com/news/516961/how-tesla-is-
dri...](http://www.technologyreview.com/news/516961/how-tesla-is-driving-
electric-car-innovation/)

------
slfnflctd
Yawn. I've been following this concept, and a wide array of very talented
scientists working on it, for years now.

Any of the below projects, should they ever see the light of day (you'd think
out of this many, at least one will make it eventually), stands a good chance
of being quite superior for this application in just about every way:

[http://www.eosenergystorage.com/technology-and-
products/](http://www.eosenergystorage.com/technology-and-products/)

[http://www.ambri.com/technology/](http://www.ambri.com/technology/)

[http://www.ultrabattery.com/technology/](http://www.ultrabattery.com/technology/)

[http://www.axionpower.com/Technology](http://www.axionpower.com/Technology)

[http://www.lightsail.com/](http://www.lightsail.com/)

[http://www.drexel.edu/now/archive/2014/November/MXene-
clay/](http://www.drexel.edu/now/archive/2014/November/MXene-clay/)

~~~
ThomPete
Very rarely the best solution wins.

~~~
bengali3
Agreed. Also, which definition of 'win' is agreed upon here. Win by
efficiency? Win by market cap?

Edit: hint, look out for the very talented marketers

------
forgotAgain
Source Bloomberg article
[http://www.bloomberg.com/news/articles/2015-02-12/tesla-
plan...](http://www.bloomberg.com/news/articles/2015-02-12/tesla-planning-
battery-for-emerging-home-energy-storage-market)

------
boris
Today I went to pick up two 100AH lead-crystal batteries for a long-run UPS
(we now have regular load-shedding here in South Africa). If I believe all
what I have read about them online, they are amazing, compared to lead-acid.
Crazy heavy though (33kg each).

------
Altenuvian
I see 'em audiophiles drooling over this.

just look at this homemade battery in some audiophiles basement:

[http://6moons.com/industryfeatures/roadtourlivingvoice/3.htm...](http://6moons.com/industryfeatures/roadtourlivingvoice/3.html)

------
BurningFrog
Tesla could offer an "attachment" to their cars that let them serve as a home
battery when parked.

You'd have to let it charge up before going driving, but for home owners who
don't drive much, that could be very cost effective.

Unless I'm missing some complication?

~~~
thinkcontext
Batteries have a limited number of charge/discharge cycles. If you use your
car to power your home you'll have to replace the batteries that much sooner,
at a cost of $thousands. Electric car buyers are paying a premium to have the
batteries be mobile, better to use them for that application.

------
vermontdevil
Wonder how this would compare with Bloom Energy Server[1]

I recall Apple made some purchases or investments in these products.

[1][http://www.bloomenergy.com/fuel-cell/energy-
server/](http://www.bloomenergy.com/fuel-cell/energy-server/)

------
psaintla
Why is living off the grid the main objective here? I live in a suburban area
that occasionally has power outages. Right now I'm considering the purchase of
whole house generator but if I could have a battery instead I'd do it.

~~~
Filligree
You can have a battery instead. You can get a battery right now; lead-acid
will work just fine, if we're talking power outages of an hour or less.

House-sized UPS systems are a thing. An expensive thing, mind you, though I
don't know how expensive.

~~~
psaintla
Yeah, I looked into that and last I checked it is prohibitively expensive. If
this is a viable alternative I can see two great uses.

1.) Whole house UPS 2.) A way to take advantage of significantly lower night
time electric rates.

------
buckett
Maybe having a battery pack like this at home would mean you could recharge
your Tesla car much faster as you're not limited by the grid supply to your
home? A bit like having your own Supercharger station at home?

------
diltonm
We could have used this last week. A pole was damaged (I don't know how, just
that it was damaged) and in the middle of a sunny day we lost power for 1.5
hours. Really looking forward to this technology.

------
wavesum
What puzzles me is the timeframe presented. What is the point of starting
production in 6 months if the gigafactory is not up yet, and TSLA is
production constrained just making the car batteries?

------
Iv
The last piece for a wind-solar future. Ok, if this really comes to the market
and can store 12-24 hours of a typical household consumption, we may be able
to live off solar and wind.

------
krenoten
Are orange and red terminals confusing to users? (I'm an electronics noob,
maybe this is a convention)

------
nacnud
Does anyone know if these could be a feasible energy store for people living
on the Moon or Mars?

------
caniscrator
If we were able to create individual or community power grids; imagine how
much infrastructure could just be removed. Maintained by the individuals
owning it, instead of these stupid power companies and the way they work now.

------
offgridquest
We have all lived through the improvements in construction with tools that
don't need to be plugged in and phones that are unplugged. The next logical
step is homes that are unplugged and self power generating. There is an
incredible gap in society in the U.S. created by the tax code whereby if you
make $25,000 and are a family of 5, you receive enough tax and food benefits
and medical insurance to be equal to the person that makes $65,000 per year.
And if your income increases to $45,000, you will be losing money, so there is
no motivation to reach that point. The Living Off The Grid topic has gone
viral because those stuck in the gap seek a way up without increasing income,
because it's hard to increase income without hurting oneself. But the idea of
downsizing and saving up has become popular with it. Getting a little plat of
land and a trailer or a tiny house for a time while saving up.... growing
food, having chickens, all are ways to save up and gain without actual cash
income increase. Adding solar power to the mix helps prevent power bills. It
is also a terrific way to fire the local monopoly power company, who may or
may not in your area have any decency of customer service. Without
competition, why would they have to care. But the off grid movement is pulling
the carpet out from under these government allowed monopolies and forcing
competition. In the same stroke, it removes the tax burden from the homeowner
that was included in the electric bill. If you have a solar or wind power
system and charge your Tesla car too, then you have a completely tax free
energy system. It sounds like it's taking away from the government, but the
neat thing is, this can also be used to alleviate financial strain on the
government. If you can provide a self powered mobile home with rain-water
collection to section 8 housing, then the government is also saving on those
utility expenses. And land is cheaper a little further out. I recently bought
10 acres in Creek county Oklahoma. The power company wanted $10,000 to add one
pole into the land and connection. I opted that it was better to spend that
money on a solar power system. The same was true of water with huge expense,
so I opted for rainwater and later to add a well. The up front costs
associated with being on the grid for many rural areas, or adding more power
poles is really more than costs will continue to be as they come down down
down for self power generation. This is all exciting to me. We have to
consider total impact. Hydro power is still a hugely terrific producer of
energy. Rain that fills the lake.... the lake is a battery.... stored to
produce energy. So rain makes our energy. This is still a much better solution
than building batteries for large power needs. Yet the infrastructure and
labor required to put in poles and wires is too high for homes in light of
these modern developements. I look forward to an exciting and bright future.
~David Webster Offgridquest.com and Facebook's Living off the Grid

------
harkyns_castle
Go go Musk you bloody champion. If we can harness the sun, waves and wind and
store it in batteries, and perhaps making those batteries is bad, it's a
better solution than continually burning fossil fuels that are destroying our
forests, species, economies, and faith in humanity. I say keep doing what
you're doing (unless I'm proved wrong).

