Musk's Powerwall

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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pdxpyro
Posts: 26
Joined: Fri Jul 01, 2011 4:18 pm

Re: Musk's Powerwall

Post by pdxpyro »

Well, if you take my roof (larger than most) getting packed out by about 416 ft2 of panels that produces about (generously) ~25% of my annual kWh consumption of 19,000 kWh, the system would be producing (again, generously) about 5,000 kWh annually. I think we came to consensus that average consumption in US was about 13,300 kWh annually. So, my big roof would only provide enough real estate to produce (at most) 38% of an average homeowners use. I just don't see where we can get to residential solar based on rooftop installations alone.

That's not all to say we shouldn't move in that direction. I just think it makes the Powerwall "iffy" for most uses. I think you're correct, though. I think those folks wishing to go gridless will be the bulk of early adopters, and use the Powerwall to time-shift align their production/consumption. I just don't see where they're going to get the rest of their power.
Skipjack wrote:There are people that have to pay 10,000 USD or more just for getting a connection to the grid. I think they are going to be among the early adopters.
Oh and I still disagree on the roof surface thing. I showed an example earlier, of a pretty average installation. It is not THAT huge. Of course it depends on your roof... Sky scrapers are going to have more problems with that, since they have comparably little roof area compared to the amount of power they need.

paperburn1
Posts: 2484
Joined: Fri Jun 19, 2009 5:53 am
Location: Third rock from the sun.

Re: Musk's Powerwall

Post by paperburn1 »

I guess it just depends on your usage. I use about 650 KWhr a month. My average bill is 80 to 100 dollars in an all electric house. one freezer,one refrigerator, microwave, stove, one heat pump, two TV , water heater, laptop and associated equipment.
I think I burn though the watts
I am not a nuclear physicist, but play one on the internet.

Skipjack
Posts: 6805
Joined: Sun Sep 28, 2008 2:29 pm

Re: Musk's Powerwall

Post by Skipjack »

Well, this panel, should be able to do about half of what you need with your roof surface area (you would have to expand it a bit to cover all of your roof):
http://www.homedepot.com/p/Grape-Solar- ... 5yc1vZbm18

pdxpyro
Posts: 26
Joined: Fri Jul 01, 2011 4:18 pm

Re: Musk's Powerwall

Post by pdxpyro »

Right. The link you have is for a 5.3 kW system. At 3.5 hours sun / day (Pacific NW), we have 18.55 kWh/day, or 6,770 kWh/year. This gets me to about 36% of my demand. (Or, about 51% of an "average" household demand - as you pointed out!).

I still don't see any "extra" that needs to be captured by a Powerwall (getting back to the topic). Am I missing something?
Skipjack wrote:Well, this panel, should be able to do about half of what you need with your roof surface area (you would have to expand it a bit to cover all of your roof):
http://www.homedepot.com/p/Grape-Solar- ... 5yc1vZbm18

Skipjack
Posts: 6805
Joined: Sun Sep 28, 2008 2:29 pm

Re: Musk's Powerwall

Post by Skipjack »

pdxpyro wrote:Right. The link you have is for a 5.3 kW system. At 3.5 hours sun / day (Pacific NW), we have 18.55 kWh/day, or 6,770 kWh/year. This gets me to about 36% of my demand. (Or, about 51% of an "average" household demand - as you pointed out!).
Yeah, but that thing does not fill your entire roof...

Giorgio
Posts: 3061
Joined: Wed Oct 07, 2009 6:15 pm
Location: China, Italy

Re: Musk's Powerwall

Post by Giorgio »

pdxpyro wrote:Right. The link you have is for a 5.3 kW system. At 3.5 hours sun / day (Pacific NW), we have 18.55 kWh/day, or 6,770 kWh/year. This gets me to about 36% of my demand. (Or, about 51% of an "average" household demand - as you pointed out!).

I still don't see any "extra" that needs to be captured by a Powerwall (getting back to the topic). Am I missing something?
Most wealthy class families around Europe don't use more than 4000 to 5000kWh/Year.
Average home in Italy uses less than 3000 kWh/Year. If they already invested in a 3 kW solar system (or if they bought a home with a solar system already included) it could make economic sense for some of them to invest in a Powerwall and get off grid, especially if prices will become lower as production scales up.

Italy standard electricity values for a 3KW residential contract:
1kWh all included up to 2700 kWh/year about 0.27 $ plus local taxes if applicable.
1kWh all included over 2700 kWh/year about 0.53 $ plus local taxes if applicable.

I might even consider getting a couple of them if price drop enough just for leveling voltage spikes and overpass the several black out that we experience monthly.
A society of dogmas is a dead society.

RERT
Posts: 271
Joined: Mon Jun 02, 2014 9:10 pm

Re: Musk's Powerwall

Post by RERT »

I have a 2.5 kW solar system in Scotland (for the subsidy!).

I calculate I could pay $2400 for 4 kWh of diurnal storage, or $4800 for 20kwh of weekly storage, at local power prices.

The powerwall seems reasonably well targeted, but for the installation cost!

R.

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