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Tesla Energy

teslamotors.com

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Re: Tesla Energy

#521

Post by yungchin »

at-fates-hands wrote: post #365
ams6110 wrote: post #345

Earlier quoted context omitted.

I would guess for most people it would show an ROI number that is not conducive to sales. Also, what is the environmental impact of the manufacture of LI batteries at this scale? Lithium mining, processing, assembly, delivery... we can't just ignore that.

I agree. Strangely, all of these issues were conveniently left out of the article. Not sure everybody knows this, but its not economically feasible to recycle these batteries: "Recycled lithium is as much as five times the cost of lithium produced from the least costly brine based process. It is not competitive for recycling companies to extract lithium from slag, or competitive for the OEMs to buy at higher price po…

I posted the same link in this thread already, in another context, but it's relevant enough: http://www.teslamotors.com/blog/mythbusters-part-3-recycling... "The result from this process is that we are able to recycle about 60% of the ESS materials and reuse a further 10% (by weight). We currently plan to landfill only the benign fluff, which comprises about 25% of the ESS, but we expect to nearly eliminate this in the future when our volumes get higher and we can justify the effort required to separate and reuse the plastic."

Re: Tesla Energy

#522

Post by TeMPOraL »

viewer5 wrote: post #442
dragontamer wrote: post #437

Earlier quoted context omitted.

While you are correct, you can at least snuff out a gasoline fire. Lithium fires do not require oxygen, so your typical Class ABC fire extinguishers won't actually work on it. You need a class D (dry powder) extinguisher, which is very rare and expensive.

> Lithium fires do not require oxygen I thought fire is by definition a combustion reaction, meaning some kind of material reacting with oxygen. What's fire, then? (I feel like a little kid, having to ask that...)

Some substances bundle together their oxygen source (think of rocket fuel, or napalm), so they don't need to consume it from air.

Re: Tesla Energy

#523

Post by _delirium »

digerata wrote: post #518
_delirium wrote: post #513

Earlier quoted context omitted.

This is also standard with other parts of a house. For example if you upgrade your kitchen to high-end finishings (granite countertops, etc.) that it didn't have before, that increases the value of the house. Not necessarily by the amount of the purchase/installation price, though.

You don't need to obtain a permit to upgrade your countertops. I believe the only time that an upgrade could possibly increase the taxable value of your house is if the township/county knows about it (I.e., you got a permit to install it). I also live in Michigan, but haven't researched renewable energy sources vs taxable value. I'm surprised to hear the gp say they had an increase.

It varies by state, but in Texas at least, major (>$5,000) improvements to a property are supposed to be reported. You could just not report it, but that's technically illegal. Also, one thing that makes reporting compliance relatively high is that there's a separate registration requirement (for different reasons) on the construction contractor's side: contractors undertaking home-improvement projects of >$5,000 are required to use a specific type of escrow account to hold the money temporarily, in order to resolve any disputes that might arise. There are contractors who will take your payment in cash and not register an escrow account, but reputable contractors won't risk that. And if you go that route, you aren't protected against what the escrow account is designed to protect against, that the contractor does shoddy (or no) work and just walks away with your cash. So people tend to do that only if they're having the work done by friends/family.

Re: Tesla Energy

#524

Post by lotsofmangos »

DaniFong wrote: post #485
wiremine wrote: post #310

What I'd love to see is a ROI calculator that: * uses my zip code to figure out what my non-peak costs might be. * allows me to optionally calculate solar energy capture (so I can see what impact having solar would be, given the average sunny days in my area) * takes into account the wear and tear average cold weather would have on the lifetime of the batter and the payback period. For example, I live in Michigan, an…

I wish it did; we are very far from harmonizing all the different utility rates. Once that data is clean up and available, an interactive website should not be too difficult to build. If anyone is interested in doing a paid internship to help us build it, send me a note with a portfolio at dfong@lightsail.com -- I run a compressed air energy storage company.

Was going to ask if you are ever planning on doing a home system, as although compressed air tanks can be risky, presumably they are slightly less risky than normal gas supplies.

Re: Tesla Energy

#525

Post by rconti »

Florin_Andrei wrote: post #459
msandford wrote: post #287

Earlier quoted context omitted.

> only 2kW? 2kW is enough to power any residential, single-family house for 95-98% of the time You obviously don't live where it's hot. I live in Houston, TX and while I rarely run the A/C right now, in another month it's going to run on average 15 minutes per hour, every hour, for 3-4 months straight. Highs in the low 90s to high 100s and lows in the 80s (F). I have 2.5 tons of A/C which is pretty moderate. The cond…

> You obviously don't live where it's hot. It's a really strange paradox that, in places where it gets very hot during the day, we're drawing tons and tons of energy from the grid to cool the house precisely at the time of the day when even more energy is pouring down on us freely from the skies. Seriously, A/C is basically Universe's most heavy-handed hint that we should use more solar.

Yep. Just on principle, I'd have a hard time living somewhere that was insufferable without A/C. It's a clear sign you're doing something wrong.

Of course, you could make a similar argument about needing artificial heat, but that's at least far more efficient!

Re: Tesla Energy

#526

Post by edwhitesell »

giarc wrote: post #515
hammock wrote: post #463

Earlier quoted context omitted.

Fire hazard

I doubt many homes would have adequate fire separation between a garage and main home to make a difference between laundry vs garage.

It may not make much of a difference from the overall perspective of damage, but it certainly makes a difference in warning and escape time. Also, the chance of dangerous fumes while trying to escape is lower.

Re: Tesla Energy

#527

Post by rconti »

nsxwolf wrote: post #387
roel_v wrote: post #285

Earlier quoted context omitted.

There is no every-day use case where the difference in light perception from an incandescent bulb is different, or even distinguishable without measurement, from an LED bulb. Feel free to try it yourself in a light studio, or otherwise, please cite any studies with modern lamps that conclude that the 'light quality' (by whatever metric) of an incandescent bulb is higher (that is, 'higher' as in 'makes a material diff…

The subjective experience of a home lit with incandescents is very different than one lit with LEDs. I don't care if the color temperature is the same. Things just look different. The bulbs cast their light differently. There may not be a difference in "light quality", photons are photons, but if you convert a home from one to the other things will look different, and you may prefer one way or the other. And don't fo…

Yes, but being unwilling to spend 1 day adjusting to a different look is a pretty silly reason to continue to run a bunch of spaceheaters in your house that, as a byproduct, happen to produce some light.

Particularly if you ever use air conditioning.

Re: Tesla Energy

#528

Post by dragontamer »

warfangle wrote: post #486
dragontamer wrote: post #479

Earlier quoted context omitted.

Using water on an electric fire sounds like a dumb idea to me. But yeah, the MSDS does seem to say that...

A venting lithium ion battery isn't usually an electrical fire.

And what of all the molten wires that _were_ charging said battery?

Re: Tesla Energy

#529

Post by danmaz74 »

fancyketchup wrote: post #400
krschultz wrote: post #377

Earlier quoted context omitted.

I agree in the long term (50 years) that is true, but in the medium term (15 years) solar + storage might be moving faster than utility companies want. If you built a power plant with a 40 year lifespan in the year 2000, you would not be happy if peak demand is lower than expected in 2025. I would not expect the utility companies to be allies in this transition period to clean energy. It requires major capital outlay…

That doesn't really make sense. Electric utilities require capital investment proportional to peak usage, but only earn returns on average usage. This will only increase the ROIC of an electric utility by reducing the peak:average ratio. Additionally, electric utilities are in a constant cycle of capacity upgrades to keep up with increasing demand. Customers adding distributed storage allows utilities to delay capita…

> but only earn returns on average usage

Not if the price they sell at is different at different hours.

Re: Tesla Energy

#530

Post by gregpilling »

iamthepieman wrote: post #299
mauricemir wrote: post #223

Earlier quoted context omitted.

Yes talk to telco Engineers from the power side of the biz and they will have war stories about accidents and close misses with the Central Offices (Exchanges) DC power. High Voltage/Amperage DC is quiet different to AC power and i suspect that building/wiring codes are going to need to be updated if this local storage takes off.

dropped a wrench across the terminals on the deep cycle backup batteries inside a telco switching center. Had to disconnect the whole bank of batteries to fix it because the wrench welded itself to the terminals. it wasn't a tack weld either.

That makes for a very exciting day.
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