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Tesla Energy

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Re: Tesla Energy

#211

Post by jacobolus »

roel_v wrote: post #200
kondro wrote: post #32

Doesn't include inverter or installer markup and can only provide 2kW output. It will get expensive by the time you actually have all the bits you need inside your house. How is this better than deep-cycle batteries (with 20+ year lives) again? Why does it need to be slimline?

"and can only provide 2kW output." only 2kW? 2kW is enough to power any residential, single-family house for 95-98% of the time; you only need (a little bit) more than that at very short (few minutes) peak intervals - when heating up an oven, or some cycles of doing laundry. A second unit would provide that headroom, and otherwise (when the extra $5k for a second unit is prohibitive) you could still draw from the gri…

I use incandescent lights. They produce a much more pleasant spectrum than “white” CFLs or LEDs.

Re: Tesla Energy

#212

Post by IanCal »

roel_v wrote: post #197
kondro wrote: post #92

Earlier quoted context omitted.

2 is not enough. 4kW seems to be the maximum potential drain from the battery. That wouldn't power an oven… let alone anything else at the same time. 4kW inverters seem to be around the $1000 mark… but they don't seem to increase linearly (10kW inverter $4000 for example). Of course you could go totally off-grid, but the cost isn't going to be just $7k… it's likely to be at least $15-20k by the time you get everythin…

" 4kW seems to be the maximum potential drain from the battery. That wouldn't power an oven… let alone anything else at the same time." 4kW is enough to power an entire home continuously, without thinking about energy use, even a large one with a home office with several people working in it + washing machine + oven + electrical stove at the same time . I have the data to prove it, too - 10 second interval power cons…

> I never had a load of more than 3.5kW

Different issues over the pond, my kettle can draw 3kW :)

Since so many of my countryfolk have something similar, this actually causes our energy production quite severe issues when popular TV shows finish. Often a 200-400 MW spike but at the end of the 1990 world cup semi final penalty shootout against Germany, there was a spike of 2.8GW.

An interesting example of some of the problems that could be solved at least to a large degree by local batteries.

http://en.wikipedia.org/wiki/TV_pickup

I wonder if this will move more from ones in the home to ones placed by the national grid. While every house on my road might have one, and it's not enough to cover the load from a kettle, one for the whole street could cover it just fine as long as we don't boil them at an identical time (the worst case there is basically equivalent to the normal case for individual batteries).

Re: Tesla Energy

#213

Post by IanCal »

2muchcoffeeman wrote: post #75
TaylorAlexander wrote: post #61

Earlier quoted context omitted.

If you're only looking at it from a financial perspective, it may not be "worth it" (I haven't done the math). But if you want to pay a little to be able to have reliable power from unreliable sources, then it could be "worth it". It may save you zero dollars over ten years, but during that time you're provided the service from this system.

But even if the life time cost for the energy is the same, if you can afford the initial payment, why wouldn't you do it? Especially if there are other advantages to the newer technology?

> But even if the life time cost for the energy is the same, if you can afford the initial payment, why wouldn't you do it? Especially if there are other advantages to the newer technology?

There's an opportunity cost. You'd have to weigh the lost gains you could make elsewhere to the advantages.

Re: Tesla Energy

#214

Post by pikachu_is_cool »

TaylorAlexander wrote: post #108
Vik1ng wrote: post #81

Earlier quoted context omitted.

I feel like a backup generator is the last place where I would make my decisions based on the environment. I mean how long is it actually going to be active? Also batteries aren't exactly environment friendly either.

That may well be how you feel, but lately I feel like any burning of petrol is just disgusting (though I still do it as I cannot afford alternatives at the moment). I want to completely divest from fossil fuels, even for intermittent use. That's as much for the social value of saying "yeah I don't use fossil fuels and it's great" as it is for the environmental impact. I want to try all this tech to be an early adopte…

That's ridiculous.... the only way to actually achieve that is to abstain from all plastic consumption, and abstain from all electricity consumption.

Re: Tesla Energy

#215

Post by patrickg_zill »

miratrix wrote: post #181
ChuckMcM wrote: post #138

Nice, that came in lower than I was expecting. I was thinking $5K for the 7kWh unit. Of course that is the "installers" price so who knows what those folks will consider the 'retail' price. My wife still has her solar installer certification so we could presumably get one that way. It also makes for a really interesting opportunity for grid tied solar inverters. Now you want the inverter to power the house first, the…

On the grid tied solar inverter front - the spec sheet says the battery voltage is 350~450 V, so we're looking at 108 lithium ion cells (25 x 18650 cells?) at 400 VDC nominal. This is quite different from typical lead acid battery pack voltage of 12, 24, or 48VDC that's used for battery backup storage, so a lot of existing solar battery storage infrastructure may not even work... this means that people may need to bu…

48V is under the threshold at which electrical shocks become dangerous. 48V or less is "low voltage" class. And, 48V is a multiple of both 12V and 1.5V (most individual battery cells are 1.5V), making it much easier to hook up by using a combo of parallel and series connections.

Re: Tesla Energy

#216

Post by patrickg_zill »

miratrix wrote: post #181
ChuckMcM wrote: post #138

Nice, that came in lower than I was expecting. I was thinking $5K for the 7kWh unit. Of course that is the "installers" price so who knows what those folks will consider the 'retail' price. My wife still has her solar installer certification so we could presumably get one that way. It also makes for a really interesting opportunity for grid tied solar inverters. Now you want the inverter to power the house first, the…

On the grid tied solar inverter front - the spec sheet says the battery voltage is 350~450 V, so we're looking at 108 lithium ion cells (25 x 18650 cells?) at 400 VDC nominal. This is quite different from typical lead acid battery pack voltage of 12, 24, or 48VDC that's used for battery backup storage, so a lot of existing solar battery storage infrastructure may not even work... this means that people may need to bu…

48V is under the threshold at which electrical shocks become dangerous. 48V or less is "low voltage" class. And, 48V is a multiple of both 12V and 1.5V (most individual battery cells are 1.5V), making it much easier to hook up by using a combo of parallel and series connections.

Re: Tesla Energy

#217

Post by ZeroGravitas »

amass wrote: post #208
colinsidoti wrote: post #51

One thing that might go overlooked: Load shifting could, in theory, lower electric bills such that there's ROI without solar panels. --- Edit for why: On-demand power is expensive. "Spinning up" additional power during the day is more expensive than having certain types of power generation running all the time. In theory, pumping power into a battery at night during non-peak hours will cost less than consuming direct…

Doesn't this ignore completely the efficiency of the batteries? These batteries aren't ideal, you won't get out 100% of the energy that is put in. I don't know the efficiency rating, and I haven't done the math, but I suspect that the losses will cut into the savings significantly.

The page says >92% round trip efficiency. Since they also claim that they're selling them to utilities for exactly this purpose I'd guess it's theoretically possible and probably comes down to the pricing structure offered to consumers in your local area to buy and sell to the grid.

Re: Tesla Energy

#218

Post by maccam94 »

eru wrote: post #201
toomuchtodo wrote: post #110

Earlier quoted context omitted.

> utilities would quickly erase any peak-vs-non-peak arbitrage opportunities. Probably right around the same time they're no longer necessary, as the cost of distribute solar continues to plummet. Its actually truly amazing how quickly the price continues to drop for panels each year.

Depends on country. I doubt you could ever run, say, Germany or Britain on locally produced solar power.

Relevant: http://en.wikipedia.org/wiki/Renewable_energy_in_Germany

Re: Tesla Energy

#219

Post by sandstrom »

BinaryIdiot wrote: post #49
milesf wrote: post #33

Today is a big deal. Open sourcing the patents to build fully solar-powered electrical grids around the will be a paradigm shift in the power structures of the world. I expect from today onward there will be a full-scale attack from those who stand to lose because of the reduced dependency on oil. First they ignore you. Then they laugh at you. Then they fight you. Then you win.

> I expect from today onward there will be a full-scale attack from those who stand to lose because of the reduced dependency on oil. Maybe. But remember we don't have the technology yet to completely move away from fossil fuels. The biggest issue I know of is making Airplanes electric which so far has not proven really feasible (as far as I can find anyway). This solves a huge chunk of issues but there are still ple…

It's an issue for sure, but at ~5% of global CO2 there are other easier sources to target first.

https://en.wikipedia.org/wiki/Environmental_impact_of_aviati...

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