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Tesla Motors Announces a New Home Battery

offgridquest.com

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Re: Tesla Motors Announces a New Home Battery

#151

Post by sah88 »

jacquesm wrote: post #59

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 b…

Its worth noting that with lead acid most people target a ~50% depth of discharge as batteries start getting damaged when they are cycled deep. (Yes even deep cycle batteries.)

Now that also provides some additional redundancy so it's not like the other 50% is entirely useless.

Re: Tesla Motors Announces a New Home Battery

#152

Post by fche »

danielweber wrote: post #130
fche wrote: post #68

Earlier quoted context omitted.

A properly wired transfer switch fully cures that risk.

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...

(It's likely there are many -other- hazards to power line working, beyond presence or absence of transfer switches at on-site generators.)

Re: Tesla Motors Announces a New Home Battery

#153

Post by tessierashpool »

brudgers wrote: post #23

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... Mining is mining. There isn't a "green" form. Tearing holes in the ear…

    The house off the grid is built on
    industrial infrastructure.
So what? It's a matter of degree.

I helped my parents build their off-the-grid house. It's solar-powered, but uses batteries for backup storage. It collects and filters rainwater, recycles and purifies its own sewage, and is made mostly of recycled materials (in the style of what's called an "Earthship," but with a more traditional, house-like form factor).

Did industrial infrastructure come into play? Of course. We used cars and trucks to get stuff there to build with. We used machines and materials produced in the modern world. What difference could that possibly make? The house is still much less ecologically destructive than the vast majority of dwellings worldwide, both in terms of ongoing damage and initial construction.

It's possible to create buildings today which get all their electricity from the sun; which require no industrial infrastructure at all for sewage, heat, or clean water; and which cost much, much less than earlier housing models. That's an amazing improvement.

All tech's based to some degree on tech which came before.

Re: Tesla Motors Announces a New Home Battery

#154

Post by tlrobinson »

jacquesm wrote: post #109
davegardner wrote: post #99

Earlier quoted context omitted.

The same issue exists with grid connected solar panels. My solar panels are designed to stop working whenever there is a power outage. This is a legally mandated requirement here and is very annoying when it happens on a beautiful sunny day. A solar panel installer told me that if I add a battery backup to my installation, then at least it'll still charge the batteries during a power outage.

There are some ways around that limitation. The reason it exists in the first place is so that the power company can safely power down their lines without installations such as yours feeding power back into the lines that are supposedly safe. This on the off chance that you'll end up electrocuting a line-man, which makes good sense. Of course, since your puny little solar installation is incapable of powering a subst…

"you're going to have to undo all of this"

Why can't "all of this" be packaged into one idiot-proof box with connections to the grid, your off-grid system, and your house?

Re: Tesla Motors Announces a New Home Battery

#155

Post by yourapostasy »

offgridquest wrote: post #49
PhantomGremlin wrote: post #18

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 tas…

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 tw…

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.

Re: Tesla Motors Announces a New Home Battery

#157

Post by tlrobinson »

maxerickson wrote: post #134
danielweber wrote: post #130

Earlier quoted context omitted.

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...

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/ ). 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.

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

Re: Tesla Motors Announces a New Home Battery

#158

Post by spydum »

alex-g wrote: post #76
phreeza wrote: post #54

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.

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…

See fairbanks alaska: http://www.telegraph.co.uk/technology/3312118/Worlds-biggest...

Re: Tesla Motors Announces a New Home Battery

#159

Post by fps »

lsaferite wrote: post #61
brudgers wrote: post #23

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... Mining is mining. There isn't a "green" form. Tearing holes in the ear…

I wish sites would add automatic abbr tags to think like FWIW or, in this case, TANSTAAFL so those no in the know can easily mouse over and see what the hell you are saying.

Check out the google dictionary plugin for Chrome: https://chrome.google.com/webstore/detail/google-dictionary-...

You can double-click almost any abbreviation (or any other word) and get a definition.

Re: Tesla Motors Announces a New Home Battery

#160

Post by Dylan16807 »

chiph wrote: post #135
evgen wrote: post #101

Earlier quoted context omitted.

If you are going to count hydrogen emission as a problem for a lead-acid battery then you should be honest and point out that lithium batteries of all varieties have a habit of failing in spectacularly combustible ways.

Sorry - my last sentence wasn't dramatic enough. "Failure mode more like a fireworks factory burning, than the Hindenburg exploding"

Wait, are you using the Hindenburg as the worse outcome? Most of the people on it survived, and a 90 second fire is by no means an explosion.
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