Tesla just started taking orders on their Solar Roof today. Is it a good deal as promised?
You can get details on the solar roof along with a quote on the price for your house at the Tesla Solar Roof website. Plugging in the numbers there myself for our house I get :
Cost of roof = $45,100
Tax cred = -$10,700
Value of Energy = $27,400
Net cost over 30 years $7000
They make it look good that way. But what you're really doing is spending $34,400 today to get $27,400 energy over 30 years. Thats not so good of a deal.
But theres more. My state and local utility also offer incentives that combined would cut another $8800 off the price. That gets the net cost of front down to $25,600. This is a much better deal but I still don't want to spend $25,600 today for $27,400 spread over 30 years.
Really a Solar Roof is going to be best if you're already looking at the cost of replacing a warn out old roof. Our own home has a very new roof. So it doesn't make sense to tear off a perfectly good roof to put on a Solar Roof. We do have a rental property that we replaced the roof on not too long ago for about $7200. If you figure in the cost of that $7200 roof then going with a Solar Roof instead starts to make more sense. Youre not looking at spending $25,600 today for $27,400 over 30 years. Instead you're looking at spending $7200 for a regular asphalt tile roof or getting the Solar Roof for $25,600 along with $27,400 in energy. Thats really a cost of $18,400 for the energy. Now you're getting closer. But its still not really worth it.
The thing that would really make a Solar Roof worth while is comparing it to a more expensive roof. When I replaced that rental roof we got traditional asphalt shingles as you see on the majority of roofs (at least around here). However the Solar Roof is a higher quality glass material. Its more comparable to glass tile roofs or slate shingles. Those higher quality materials cost a lot more. Using those materials would cost 2-3 times as much as the asphalt roof. If you're now comparing a solar roof to a roof that is $10,000 to $20,000 then thats a different equation. Bloomberg has a graphic comparing roof costs in their article Tesla’s Solar Roof Pricing Is Cheap Enough to Catch Fire
The situation where it makes sense then is replacing a worn out old roof with a new higher end material roof. If the net cost of a Solar Roof is $25,600 and the comparable alternative is a $20,000 slate roof then you're really looking at spending $5,600 more to get the solar power. That solar power adds up to $27,400 over 30 years. The power savings starts at about $600/yr. The net present value of the 30 years worth of power is over $13,000. So you're spending $5,600 more net to get the solar power saving $600 a year with a total value of $13,00. Now that makes sense.
So while I would not run out tear off my perfectly good roof tomorrow for a Solar Roof, it could very well be worth getting one if you have an old roof that needs replacement and you were looking to use higher end materials.
One last point to make is that the Solar Roof has a "infinity warranty". They warranty it forever the life of the house. So you won't have to replace the roof out of pocket. Now I'm not sure how much thats really worth, I didn't look at the details. But that certainly does add value over traditional roof materials which need replacement. But a cheapo asphalt shingle roof should last 30 years and a nice slate roof should last 50 to 200 years. Slate roofs may as well be "forever" as far as most of us would plan. But the lifetime warranty isn't nothing.
Bottom line: Tesla Solar Roofs can be a good financial choice in the right situation. If you're looking at replacing an old roof with a higher end roof it can be a good deal. It all depends on the specifics.
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