Version 3.0 of the Tesla solar roof

[MillCreek]

https://www.wired.com/story/tesla-new-solar-roof-musk-says-will-work/?fbclid=IwAR3PtNAyO4AiX4eXDrzgzvUE9FyWEr30GM6ZSBOFiVIiMD_Sz6ghgEkBhyc&mbid=social_fb&utm_brand=wired&utm_campaign=wired&utm_medium=social&utm_social-type=owned&utm_source=facebook

If this ever gets commercially viable and affordable, I would like to look into this and a Powerwall.

[Ben]

Might become more viable in places like CA, with high electricity prices and dummies who just now, due to power shutdowns, are learning that solar panels don't mean power backup if they don't have batteries attached.

As I've said in the past, I'd be interested in this kind of setup - whether roof tiles are separate solar panels - if the powerwall would additionally let you charge it via generator. It really seems like the only reason they're not providing that as at least an integrated add-on option, is SJW environmentalism and not wanting to associate their product with evil fossil fuels.

I care much less about the environment than I do about being able to run a heater on a 5 degree day after and extended power outage and prolonged days of cloudy skies.

[Fly320s]

If this ever gets commercially viable and affordable, I would like to look into this and a Powerwall.

The Powerwall isn't worth the cost.  It doesn't store enough power to run a home, even partially, for more than a day.  It just isn't a viable solution for most of the US.

[Ben]

The Powerwall isn't worth the cost.  It doesn't store enough power to run a home, even partially, for more than a day.  It just isn't a viable solution for most of the US.

When I used their configuration page a while back, it recommended a minimum of two powerwalls for me, which would likely handle more than a day if there was some solar energy, but would knock the cost up considerably.

And again, this is why a generator integration option makes more sense to me. He seems to be marketing this to the same knuckleheads who just put solar panels alone up for the enviro-creds. And truth be told, it IS a better option for them, since they can get at least a half day of backup power. Though if they already have panels up, just getting their solar company to come back out and connect a half dozen batteries would be a cheaper option than the Tesla route.

[French G.]

Golf cart batteries or a few wrecked Prius would get you more battery capacity than a powerwall.

[dogmush]

Golf cart batteries or a few wrecked Prius would get you more battery capacity than a powerwall.

Golf Cart batteries would be a pretty horrible replacement.  13.5kWh of lead acid batteries is a ton (probably literally) of stuff to put somewhere.  Powerwalls ARE expensive, but there is something to be said for packaging.  That much capacity, and inverter, and a cooling system all packaged in a pretty convenient form factor is worth something more than just the cost of the cells. 

Could I make a system that does the same thing? Sure.  Cheaper?  Probably, although I'd need to learn a lot more about lithium cell cooling than I currently know.  Would it be easy?  Probably not.

They are also getting cheaper.  I'm starting to actually believe that we'll get to the point in the next 10 years or so that residential solar, at least in the southern US, will be able to completely fill most peoples power needs.

[Fly320s]

When I used their configuration page a while back, it recommended a minimum of two powerwalls for me, which would likely handle more than a day if there was some solar energy, but would knock the cost up considerably.

We installed roof-top solar panels this year.  And we own a Model 3.  <confession done> <I feel like I should say a few Hail Marys> <Or burn some floppy disks>

I have a whole-house propane-fueled back-up generator already.  When I asked the solar guys about installing a Powerwall as an additional backup or to charge the car, they said I would never break even on the cost vs benefit.  Partly because of the cost of the Powerwall and partly because we don't get enough sunlight here in NH.  Also, the incentives from the state and the feds (I think) only apply to grid-tied solar.  Stand alone solar power doesn't get the incentives and rebates, at least not at the state level.

So, when my power goes out on a sunny day, my generator powers my house while my solar panels just sit there doing nothing.