271–280 of 341 posts
I was pleasantly surprised to see prices quoted in £GBP - the Powerwall is available in the UK! But, we don't have enough sunlight here to run a typical house off-grid year-round, do we?
It's certainly less efficient, but still worthwhile.
Quick question for the people living in the US (Target customers of the Powerwall). What is your yearly power usage? On the website[0] they put for sizing 10kWh/day/BR. Which means 14600kWh/year for a 4 bedroom house. Here in Germany, working from home with a 4BR+office house, we are using 2550kWh/year. So, I suppose the Tesla sizing is to support a "peak day" usage, but still, I am surprised by the calculations. Thi…
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A climatization using DC current from capacitors charged with solar panels might be more interesting in mild hot regions. If I understood well AC is optimized for carrying current on long distance with minimal loss. But most electric devices use DC. They need an AC to DC convertor with some energy loss. Solar panels produce DC and is usualy converted to AC with some loss. Then, in most electronic devices, this AC is…
> What waste of energy. Shouldn't we do something about this ? Most devices which operate on DC (e.g. computers, TV) have a switching power supply, which is around 90% efficient. So for a computer drawing 100W, only about 10W is lost in the conversion of AC to DC. Larger appliances such as microwaves, ovens, and air conditioners will use AC directly without conversion to DC (except maybe to power the control electron…
His argument about the solar roof starts by equating the situation to how Tesla started out - electric cars were slow and ugly and needed to be sexy and cool to be attractive, and the same is true for solar. Except I highly doubt this is true here - do people really mind the look of typical roof-mount solar? My impression is that the upfront cost is just too high and cost recoup is just too slow. The argument for the…
It depends on the person and it depends on the house design. IMO, some roof-top solar installations look pretty ugly.
To your cost point, yeah, it's still hard to look at a lot of solar as something that works financially today for most people even with the price drops--if having an off-the-grid backup doesn't have a lot of value.
As various people here are quoting, $1K/year covers electricity use for a lot of people. Even if you double that to account for higher usage or price increases, it's hard to square that with a $20K or solar/battery installation even if you ignore maintenance and depreciation.
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'no sauna inside the apartment' Finnish problems
To give context: there are about 5,5 million Finns, and about 2-3 million saunas in the country.
For $3000 this would be easy to justify just to keep my computer and network operating. I work at home and our power goes out too frequently. Is usually just for 10-20 seconds and my UPS takes care of that. But sometimes it is out for several hours - I'll say several times per year. If I can't work, I can't bill.
Where are you seeing $3000? When I set it to 1 Powerwall it tells me: One 14 kWh Powerwall battery $5,500 Installation and supporting hardware starts at $1,000 Total estimate $6,500 Requires $500 deposit for each Powerwall
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A lot of it has to do with geography. Europe is quite a bit further north, and doesn't experience some of the heat that the US does. It always helps me to remember that Rome is further north than New York.
But many parts of Europe need heating instead of AC. I think it has more to do with house sizes. More Europeans live in cities compared to US and thus have on average smaller apartments/houses. Also there might be cultural values in the play, at least central and nordic countries are traditionally quite efficiency oriented.
[1] http://ec.europa.eu/smart-regulation/roadmaps/docs/2015_ener...
[2] https://www.theguardian.com/environment/2010/oct/08/air-cond...
Earlier quoted context omitted.
A lot of it has to do with geography. Europe is quite a bit further north, and doesn't experience some of the heat that the US does. It always helps me to remember that Rome is further north than New York.
But many parts of Europe need heating instead of AC. I think it has more to do with house sizes. More Europeans live in cities compared to US and thus have on average smaller apartments/houses. Also there might be cultural values in the play, at least central and nordic countries are traditionally quite efficiency oriented.
Is the patent for Powerwall v2 available somewhere as well? As per https://www.tesla.com/blog/all-our-patent-are-belong-you ? Just windering if it contains enough info for anyone to built a unit themselves.
The software is the special sauce. You could build your own PowerWall easily: it's just a battery box. The battery management system is the hard part.
I haven't looked into it yet, but I'm curious about using utilizing my Teslas in case of emergency for power. With 75kwh+ each (leased so no concern about cycles) I don't think I'd need a powerwall at home.
If you're concerned about emergencies: for $38 you get a self-contained LED camping lantern that lasts for 30 days on a single charge [1] at the lowest brightness, or 2 days (off at night) on full brightness. For a tiny fraction of the price of a Tesla-based emergency power solution, you could buy two of those for every room, plus an RV cooking gas burner and a big propane tank that covers heating, making food and ho…
Pretty much everything else can go out. Obviously food could spoil in an extended outage, but that's a fairly modest cost in the grand scheme of things.