I priced some solar shingles . . . $109 each for 17 watts and you drill holes throught the roof to get the wires from the back side of the shingles connected in the attic . . . I don't think there will be much of a payback at that price.
"Payback" is the least of your problems ; 1st...assume you generate 200 watts of power, then you do so at 115 volts, to run your 115 v. ...~80 amp appliance (~200 watts) Plug it in... WHOA! You have just "made" DC!...and you want to run an AC appliance? Rotsa ruck! Not on this planet!
In my landlords solar powered house all of the light fixtures ceiling fans, etc have been converted to run off of DC. everything lower than the ceiling AKA radios, microwave, etc is running off of an AC converter mounted right above the battery bank. Looked simple enough. That is unless I'm totally missing something here?
There are a lot of inverters that convert DC to AC, some use a battery bank to hold the power. This is less efficient, in the mid to high 80's because of the battery bank losses on top of the inverter losses. Then you have grid ties batteryless inverters that just feed solar power directly to the grid as it is made. This is more efficient, in the low to mid 90's. Of course if the power goes out so does you’re potential to generate electricity.
My payback on my system was the done about a year after I installed my system and the power went out. I wasn’t home but our furnace, many of the lights and fridge and freezer kept running for my wife and kids at home.
But speaking strictly from a financial standpoint a typical grid tied batteryless payback is between 10 and 25 years. A battery system is much further out since you will likely have to replace the batteries in approximately 10 year intervals depending on use, likely 25 to 50 years on payback. Again if you have a battery system payback isn't the likely reason you have it, just an added bonus.
I saw it like spending $8k on a nice generator setup, or that same $8k on a system that I use almost daily and generates electricity every day, where the generator just sits there and does nothing.
A small annoyance: why did they overdub the "motor" sound effect nearly every time the car goes by? Sounded even like a turbine at times. It seems silly to consciously try to make the car more "Jetson-y" than it really was.