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Powerwall 2 and Integrated Solar

powerwall.tesla.com

321–330 of 341 posts

Re: Powerwall 2 and Integrated Solar

#322
post #278

Earlier quoted context omitted.

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.

I think you're right about house sizes, but there are a lot of the US that needs both summer AC and winter heating - like the midwest, the north east, and probably the west coast east of the mountains (inland Washington, Oregon).

Insulation is key. From what houses I've seen in the US vs Europe, the former are mostly wood-based (or similar material) and thin-walled, whereas Europe's houses are often stone- or concrete-based, thicker walls and/or (at least for newer/refurbished houses) very good insulation.

Combine that with some (more or less) clever thermal management and you need way less for both cooling and warming the house. There's also multiple government programs/incentives to improve housing energy consumption efficiency.

Re: Powerwall 2 and Integrated Solar

#323

Earlier quoted context omitted.

If you generate more electricity than you use during the day, you all of a sudden don't have an electric bill... or a drastically reduced one. The funny thing about solar... it's not constant. Half the day is night... then clouds/rain/etc. 24/hours of electricity is for those dry periods.

It will take most people 20-30 years to recoup this in terms of an investment over wholesale energy costs at current rates. It is, for the present a gimmic.

That depends entirely on where you live.

My parents in Australia have almost paid back their 10Kw system, in less than 5 years.

Re: Powerwall 2 and Integrated Solar

#324

Earlier quoted context omitted.

It might be (it is) anecdotal, but as someone from Europe it struck me odd how much Americans love their A/C. Too much, in fact. Almost everywhere I went it was too cold. Somewhat like in SE Asia. That might be the answer to high energy use.

It's worth noting that temperature control is only half the equation. In places like Houston, A/C plays a big part in controlling indoor humidity as well(for both comfort purposes and to prevent mildew from growing all over everything).

There's other (read: more efficient) ways to control humidity than using an A/C. Including making buildings more "airtight" so the dampness doesn't leak into the house (as long as you don't open doors/windows too much, of couse).

Re: Powerwall 2 and Integrated Solar

#325
post #321

I suspect that Tesla will exponentially improve the capacity and performance of these Powerwall units every couple of years.

Exactly the reason that many people are wise to hold off on installations. The long term cost savings are wasted if future products are exponentially better in the short term. Non-financial benefits aside, naturally.

Re: Powerwall 2 and Integrated Solar

#326

Earlier quoted context omitted.

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.

It's much, much better to burn fossil fuels for heat than to burn fossil fuels to spin turbines, transmit the electricity long distances, and then run it "back" through heating elements. Stages one and two are pretty lossy. Particularly when electricity is from coal and natural gas power plants, using it for heating is a staggeringly bad idea.

True, but electric powered heat exchangers can give a 2-8x advantage since it's not generating the heat, just moving it from one place to another.

Re: Powerwall 2 and Integrated Solar

#327
post #278

Earlier quoted context omitted.

I think you're right about house sizes, but there are a lot of the US that needs both summer AC and winter heating - like the midwest, the north east, and probably the west coast east of the mountains (inland Washington, Oregon).

Do people need air-conditioning or is it just a luxury? I guess now the globe is heating up there is more need for one, but I've always thought of it as borrowing from the future a little, a viscous cycle. More AC, More emissions, needs more AC. I'm in Indonesia right now and sure the houses are built for the tropics but with locals, AC is rare and people manage to get plenty of good sleep and have loads of energy.

It's rarely productive to talk about "need". Do you really need indoor plumbing? Do you need a private bedroom? A broad variety of foods? After all, plenty of people in the less developed parts (and in the near past in the more developed parts) of the world get by without those just fine.

The history of civilization is largely the history of the taming of nature to better suit the needs (and wants!) of humans.

Re: Powerwall 2 and Integrated Solar

#328

So I used the calculator on Tesla's web site, in my case, I'd want 3 powerwalls and I'd want a solar installation to complement it: $18,000 USD. That's still way too high: $1,800 - $2,500 would have been acceptable. That is how much I'm willing to pay for some solar panels, three batteries, and a little bit of electronics (processed sand) to control the lot. As far as I'm concerned, this is all still hype. Prices nee…

A more interesting metric might be months of pay back time. $1,800-$2,500 seems like an arbitrary number you made up. Like if your power bill averages $150 (I realize it probably doesn't) and you plan to stay in place for a few years, then something like 50*$150=$7500 is easy to consider and is much higher than the numbers you tossed out (that's just over 4 years to pay you back). I mean, I agree with the point you a…

A more interesting metric might be months of pay back time. $1,800-$2,500 seems like an arbitrary number you made up.

It is an arbitrary number I made up!

Which part of that is how much I am willing to pay requires additional clarification?

I mean, I agree with the point you are implying, that people won't be overwhelmingly excited with solar until the payback goes below 2 or 3 years,

That's exactly right, and more: I am not willing to amortize their research and development costs outright. That's something Tesla (or any other company, for that matter) will have to do over years, at least as far as my wallet is concerned. Amortizing research & development costs outright is just pure greed; I won't support it.

Re: Powerwall 2 and Integrated Solar

#329

Earlier quoted context omitted.

A more interesting metric might be months of pay back time. $1,800-$2,500 seems like an arbitrary number you made up. Like if your power bill averages $150 (I realize it probably doesn't) and you plan to stay in place for a few years, then something like 50*$150=$7500 is easy to consider and is much higher than the numbers you tossed out (that's just over 4 years to pay you back). I mean, I agree with the point you a…

A more interesting metric might be months of pay back time. $1,800-$2,500 seems like an arbitrary number you made up. It is an arbitrary number I made up! Which part of that is how much I am willing to pay requires additional clarification? I mean, I agree with the point you are implying, that people won't be overwhelmingly excited with solar until the payback goes below 2 or 3 years, That's exactly right, and more:…

It is an arbitrary number I made up!

My point is that this is not really a good way to make financial decisions. If you've bought a house and plan to stay, spending up front to save over a decade is something to work at. Consider the rule of 72. Something that pays back in 10 years is yielding a roughly 7% return. That's a great return. As I said, I'm right there with ya on waiting until it makes good financial sense to make such purchases, I just think it is also a good idea to do some analysis to figure out what that means (and if the purchase makes sense, who cares what it means to the company selling).

Re: Powerwall 2 and Integrated Solar

#330
post #134
post #109

https://www.tesla.com/solar For people like me who missed the solar roof.

Thanks! Can someone tell me what kind of architectural style does that house on the landing page represent?

You got 4 different answers. Something just isn't right with that:

    Modernist
    Deconstructionist Modern Style
    Muskhaus
    Contemporary
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