# Forums

## solar glass roof

i cant shake this off my mind , i think this is gonna hit the next reveal . what do u guys think ???

Nexxus | 2016年8月25日

No. Not feasible. Costs too much for the return on your money and doesn't provide near enough space/power to charge the batteries. At best it could power an internal fan to cool the interior.

cquail | 2016年8月25日

No not much surface area to work with. Do you want your hood to be solar too?

dsvick | 2016年8月25日

Here is the last discussion on it:
https://forums.tesla.com/forum/forums/solar-roof-1

Rocky_H | 2016年8月25日

Do you drive about 9 miles a week?

andy.connor.e | 2016年8月25日

Free miles is free miles. Even if it was only able to charge 5-10% of the battery in a full day of sun exposure, thats still 10% for free. Its literally free miles while your car is sitting outside not being used. Or while being used, it could run some of the low-energy commodities on the interior. I think its a worthy investment.

Red Sage ca us | 2016年8月25日

Free inches is free inches.

leskchan | 2016年8月25日

This is not possible. Let me tell you about it as an solar panel home owner.

I lived in sunny So. California. I have 32 solar panels. Each solar panel is about 65"x40". You can only fit one of these on your car roof. These panels are mounted to face the optimal direction, pitched to right horizon, no shading. The best day I have, in any year, they produce 52kWh hours. This is the best case scenario. Fun fact, this wouldn't be enough to charge the current base model of 60kWh battery, provided I don't use any electricity for the house.

Let's do the math. Assuming the best case scenario. One panel would produce 1.625kWh maximum for the whole day. Using S 60 as the baseline. 60kWh would get you 215 miles. So 1.625kWh would get you 5.8 miles.

You decide.

Rocky_H | 2016年8月25日

@andy.connor.e, They are NOT!!! free miles. It costs extra money to design, test, install, acquire, store, supply chain, etc. those panels to have mounted on the car. You will be paying extra money (A)rolled into the car because of the R&D and (B) on the option itself to have them on your car for a pitifully useless amount of range. So you pay for it; it's not free.

Seriously, folks. Upfront investment has a payoff time. Eventually, it may flip over from the initial negative, to zero, and to positive if you keep it and use it long enough.

leskchan | 2016年8月25日

@Rocky_H is right and more.

Even for Home Solar Panel, the idea is not to use it replace 100% of your home electricity usage. Some people even think they should produce 120% and sell the 20% back to power company. That's wrong because cost of production solar energy production. The idea is bring your usage back the lower pricing tier of your grid rate.

For example, power company charges Tier rates to encourage conversation or less load on their grid, example

Tier 1: 300 kWh @15 cents per kWh
Tier 2: 301-350 @30 cents per kWh (warning you to conserve)
Tier 3: 350 or more @60 cents per kWh (penalizing you for wasting energy)

Typical solar panel system produces power at about \$20 cents per kWh. So you want to size your system to cover enough to bring your usage down to Tier 1, because it is cheaper. For the extreme, it doesn't make sense to produce excess at \$20 cents and sell it to power grid at \$15 cents.

The key is to design your system with room to grow, like adding a EV.

stevenmaifert | 2016年8月25日

These threads never end. There's not enough surface area there for anything practical outside of trickle charging the 12V battery, which the solar panel on the spoiler of my wife's Leaf does.

Rocky_H | 2016年8月26日

Reading "\$20 cents" and "\$15 cents" is giving me a headache.

topher | 2016年8月26日

"Typical solar panel system produces power at about \$20 cents per kWh"

Not anymore it doesn't. Around me in the Northeast, with not great solar insolation, solar is between 7¢ and 10¢ per kiloWatt-hour. And that price is dropping.

Thank you kindly.