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Tesla Solar Roof is on life support as it pivot to panels

electrek.co

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Re: Tesla Solar Roof is on life support as it pivot to panels

#351

Post by akerl_ »

brikym wrote: post #348
gwd wrote: post #243

Earlier quoted context omitted.

I mean, if your goal is to absolutely maximize the number in your bank account, no. But then there are other things you could be doing too -- you can do the math and cover all your nutritional needs for under $1 a day, by eating mostly potatoes. But most people prefer to spend 20x that much and have food that tastes decent. And a handful of people will spend 30-40x that to have really nice food. If you think about mo…

I don't get it. If it's cheaper to have a nice traditional slate/cedar roof and just buy my electricity from the grid then why would I want solar tiles? Just to tell my friends how I'm saving the planet? It's not like solar tiles have a monopoly on electricity or nice roofing materials.

Before I bought a solar roof, I used to really struggle for things to talk about when I met new people.

I was considering joining a Crossfit gym but that seemed really strenuous so the next best thing was sending a truckload of money to Tesla.

Re: Tesla Solar Roof is on life support as it pivot to panels

#352

Post by freetime2 »

brikym wrote: post #348
gwd wrote: post #243

Earlier quoted context omitted.

I mean, if your goal is to absolutely maximize the number in your bank account, no. But then there are other things you could be doing too -- you can do the math and cover all your nutritional needs for under $1 a day, by eating mostly potatoes. But most people prefer to spend 20x that much and have food that tastes decent. And a handful of people will spend 30-40x that to have really nice food. If you think about mo…

I don't get it. If it's cheaper to have a nice traditional slate/cedar roof and just buy my electricity from the grid then why would I want solar tiles? Just to tell my friends how I'm saving the planet? It's not like solar tiles have a monopoly on electricity or nice roofing materials.

Solar Roofs can still pay for themselves, it's just a much longer pay back period than with commodity panels. So I guess the Solar Roof strikes a balance between economic benefit and design that makes sense for some people.

> Just to tell my friends how I'm saving the planet?

This is a really uncharitable framing that I often see repeated that wealthy people are only motivated by how other people perceive them. And sure, that probably plays a part for some people. But maybe they just feel good about saving on their electricity bill in the long term and reducing their carbon foot print - even if it's not the most economical or environmentally friendly option available?

Re: Tesla Solar Roof is on life support as it pivot to panels

#353

Post by akerl_ »

freetime2 wrote: post #352
brikym wrote: post #348

Earlier quoted context omitted.

I don't get it. If it's cheaper to have a nice traditional slate/cedar roof and just buy my electricity from the grid then why would I want solar tiles? Just to tell my friends how I'm saving the planet? It's not like solar tiles have a monopoly on electricity or nice roofing materials.

Solar Roofs can still pay for themselves, it's just a much longer pay back period than with commodity panels. So I guess the Solar Roof strikes a balance between economic benefit and design that makes sense for some people. > Just to tell my friends how I'm saving the planet? This is a really uncharitable framing that I often see repeated that wealthy people are only motivated by how other people perceive them. And s…

It's possible the math works out differently for people whose roof already needs to be replaced, or for people whose roof can be nearly totally covered with generating tiles.

In my case, it's been a while since I crunched the numbers but the pay back period is effectively infinite, assuming that had I not bought the roof I'd invested the money instead. This is especially true as temperatures continue to swing more and more widely (winters that push below the efficient window for my heat pumps are murderous on my banked solar energy) and more states and electric companies switch from net metering to newer rate plans.

Re: Tesla Solar Roof is on life support as it pivot to panels

#354

Post by AngryData »

youngtaff wrote: post #320
ChoGGi wrote: post #312

Earlier quoted context omitted.

It took about three weeks of labour and just under three grand in cost to redo the shingles on my roof. It was just over two grand for the shingles, the rest for misc. Not including me taking two weeks off of work. About three weeks because I didn't do it all at once, an 11/12 pitch is tiring to work on. One week per side of stripping/waterproofing, then a couple weekends of shingling. Edit: the stripping took a week…

When we moved in I had my house re-roofed to add insulation and a breathable membrane Took a day to take all the tiles off the front, add insulation, membrane and batten it. Then another half day or so to put the original tiles back on Back took slightly longer because we had some alterations done but it was just over a week in total effort

If he had been paying a crew and not doing it themselves most roofs can be done in part of a day with shingles. And most often by meth addicts or illegal immigrants because nobody else will do that horrible job for the prices they ask, not to mention a skilled tradesmen.

In some areas when big enough hail or storms goes through a town 1 or 2 crews will jump on the insurance payouts and take the low bid if they can do them all at once. And within a week or two at worst the entire neighborhood or small town is reshingled.

Re: Tesla Solar Roof is on life support as it pivot to panels

#355

Post by AngryData »

IshKebab wrote: post #306
grosswait wrote: post #289

Earlier quoted context omitted.

Economics. No one lives 150 years, so why pay for someone else’s roof when you’ll be making payments for so long.

Someone else suggested that you have to replace your roofs every 25 years though. People definitely live for 25 years!! Also even if you personally don't live that long, it does affect the value. For example a 99 year lease on a property is considerably less valuable than a 999 year lease, even though very few people live more than 99 years.

25 years is common but most places allow 2 or 3 shingle overs that don't require a tearoff. They just slap a naked layer of new shingles over the old which is even cheaper than the first roof/layer.

Re: Tesla Solar Roof is on life support as it pivot to panels

#356

Post by bruce511 »

throwaway2037 wrote: post #242
bruce511 wrote: post #179

Earlier quoted context omitted.

I'm in the same camp as you. I'll add that my panels are returning 16% on capital spent, and it's going up as electricity prices go up. So, yes, I could probably get a higher return if I invested that capital elsewhere, but, apart from the diversification, I get benefits beyond the raw financial return. Firstly, earlier this year, we had a cable coming into the house fail. By the time the electrician and city had don…

> my panels are returning 16% on capital spent Can you share your calculations?

The inverter keeps a log of electricity generated, used, battery used, imported and so on.

I put that in a spreadsheet which calculates money saved. (Which is reasonably complex because of pricing tiers although fortunately I don't have to deal with daily pricing changes.)

Then some math returns the return on investment per month and per year.

Re: Tesla Solar Roof is on life support as it pivot to panels

#357

Post by bruce511 »

mschuster91 wrote: post #250
throwaway2037 wrote: post #242

Earlier quoted context omitted.

> my panels are returning 16% on capital spent Can you share your calculations?

Not OP but I'll run what I plan on doing. In Germany you can get a plug-in ready kit with 2.2 kWh battery and 920W panels for less than 600€ [1]. The panels are about 1.8 m² each (=3.6 m² total), so with on average 1.200 kWh/m² solar radiation and 25% efficiency I'm looking at up to 1080 kWh in energy I'll get out of the system per year. Electricity here in Germany is expensive at an average 30 ct/kWh, so the panels…

Your numbers are likely off by about half (in Germany your sunlight is less than 1200w/m2, panels are more like 22% effecient, you'll gave at least some cloudy days, your panels won't be tracking the sun.)

But a small system is still going to bring a return and is cheap to install. And it'll give you a real way to understand the concept and to experiment.

I started with a 660w small system, and it gave me lots of insight for planning my current system.

Re: Tesla Solar Roof is on life support as it pivot to panels

#358

Post by throwaway2037 »

bruce511 wrote: post #356
throwaway2037 wrote: post #242

Earlier quoted context omitted.

> my panels are returning 16% on capital spent Can you share your calculations?

The inverter keeps a log of electricity generated, used, battery used, imported and so on. I put that in a spreadsheet which calculates money saved. (Which is reasonably complex because of pricing tiers although fortunately I don't have to deal with daily pricing changes.) Then some math returns the return on investment per month and per year.

Do you also subject the cost of upfront capital? Example: Imagine that you didn't have the upfront captial, and you needed to borrow it "from a bank" at X% for Y months.

Re: Tesla Solar Roof is on life support as it pivot to panels

#359

Post by mulderc »

rootusrootus wrote: post #161
mulderc wrote: post #94

Earlier quoted context omitted.

West coast cities like Portland and Seattle both have very good transit and in my experience is generally better than driving since traffic and parking are awful. Where I live on the west coast is a mid sized city and transit is completely viable, my family only drives on weekends for example.

> West coast cities like Portland and Seattle both have very good transit I live in Portland. Traffic is often quite slow. And even then it is much faster than public transit unless your destination is just a few miles away and on the same line.

Public transit is much faster for me but I lived near the Hollywood district and worked downtown.

Re: Tesla Solar Roof is on life support as it pivot to panels

#360

Post by formerly_proven »

mschuster91 wrote: post #247
formerly_proven wrote: post #235

Earlier quoted context omitted.

10k for a SFH roof seems extraordinarily cheap to me for any COL area. I would expect around 50k-60k for a 1000 sq ft roof (not US).

> I would expect around 50k-60k for a 1000 sq ft roof (not US). That's about 90 m². Here in Germany [1], if it's just replacing tiles, you're looking at 10k, add 20k for adding heat insulation - and you can get 15-20% back with government assistance from that sum. The only way you reach 50k in costs here is if you have to fix structural issues (e.g. rotting wood due to water ingress, but if you take proper care of yo…

I included the structure because I only know of cases (including my own) where both needed replacing. Centuries for the wood structure is hypothetically possible of course, but only if maintenance is ideal (no water ingress) and without insects. Once there are water issues, they rapidly decay. Retrofitting both new insulation and additional roof loads like solar is also not possible for every old roof structure. The flat roofs somewhat common in 60s and 70s construction also have very short lives and often need to be replaced wholesale after 40-50 years. Despite the reputation, they're not at all cheaper than traditional roofs, at least not when you have to adhere to the current building codes
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