Does it actually make sense financially vs investing in something else?
If you think about money as a tool to maximize your "joy", then whether the Solar Roof is worth it completely depends on your preferences and your financial situation. Most people are fine with black panels; but if you have the money and like the look of the tiles, why not?
> 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?
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.
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.