Cost of Tesla Solar Roof Tiles

[brucet999]

a bit more technical data on exactly how the roof goes on, electrical connections and such would be appreciated.
Is it perhaps a membrane goes down on roof, then some kind of grid the tiles go in,
how do they couple? is it inductively?
Does each tile have an inverter with MPPT built in?
how do you get the electrons collected?

I discussed this with a Solar City rep who had just been to their internal orientation meeting. Installation will be very much the same as concrete tiles, clay tiles or slate. The difference is that there are little sockets in the top edge of each solar tile for wires to plug in.

Since the solar roof is meant to partner with the new Tesla Power Wall, which has an inverter inside, we can be certain that power from tiles is delivered as DC. Presumably several tiles would be ganged together in series, then each group connected to the inverter.

Micro inverters would be too bulky to fit under tiles on solid sheathed roofs as current practice requires. Even if they could be made flat and thin enough to fit under the next row of tiles, without air circulation around them they would quickly overheat and die. Even the first generation of micro inverters had heat failure problems when mounted to the underside of solar panels with 4" of air space above the roof surface.

 

[Sodamo]

Bruce, were you able to get any specific info about the Powerwall2 from the rep?

 

[Nigel Tufnel]

I half expected Elon to proclaim: "Our solar roof will consist of the most beautiful tiles ever designed, will be essentially free after tax credits, and we can have your roof installed next week." He is wedded to the over-promise and under-deliver management concept.

Of course, I'm planning to get one anyway, I'm addicted to the Kool-Aid.

 

[brucet999]

It would be really good if the Tesla roof maximized output during partial shade. This can be achieved using microinverters with conventional panels, but I don't see how that would work with the tiles.

There are devices now called power optimizers that isolate and condition DC power output from each panel of a conventional solar array, solving the shade and damaged panel problem. I don't know whether they can be made small enough to work with the Solar Roof.

 

[brucet999]

Bruce, were you able to get any specific info about the Powerwall2 from the rep?

No, I did not.

 

[Pacific]

At the Green Festival in San Francisco a few weeks ago, I asked the rep at the Solar City booth how much the solar tile roof and installation wd cost for an approx 2k square foot roof. Was told $4500-7500 installed but I was highly skeptical. Hope I'm proved wrong.

 

[30seconds]

We obviously don't know details about connections and install time/ training, but as this is a known issue I am sure that these were designed from the start for ease of install

 

[Shawn Snider]

Haven't read the whole topic, but how would these tiles fare in Winter / Freezing?

 

[3Victoria]

Since no one has seen these tiles except at a distance, and we have no details, answering that is difficult. EM did claim that the would last a long time. My uneducated guess is that they will hold up fine in all but extreme weather (less than -50oC).

 

[ecarfan]

At the Green Festival in San Francisco a few weeks ago, I asked the rep at the Solar City booth how much the solar tile roof and installation wd cost for an approx 2k square foot roof. Was told $4500-7500 installed but I was highly skeptical. Hope I'm proved wrong.

I am also skeptical of the accuracy of that information. Hard to believe that a junior level (my assumption) SolarCity employee would have that information at this point. It does seem incredibly cheap. Certainly that price is predicated on the roof underlayment material being in place and in good condition and would likely not include connecting the tile output to the inverter or any other pieces of a solar system. The labor involved in placing, securing, and fitting to the roof shape would be significant.

 

[brucet999]

Haven't read the whole topic, but how would these tiles fare in Winter / Freezing?

They are made of tempered glass, so they will do fine in cold weather, unless you plan on throwing boiling water on them in -40º weather, of course.

 

[brucet999]

At the Green Festival in San Francisco a few weeks ago, I asked the rep at the Solar City booth how much the solar tile roof and installation wd cost for an approx 2k square foot roof. Was told $4500-7500 installed but I was highly skeptical. Hope I'm proved wrong.

I think your skepticism is well placed. That price range would work out to $225 to $375 per square, which is roughly equal to materials-only cost of concrete tiles or terra cotta, products with no electrical capabilities.

 

[macpacheco]

I'm confused... Musk stated their solar roof tiles *might* be cheaper than regular roof with the electricity free.
He also said he can't make a firm, definitive statement yet that this will be true.
I'm thinking perhaps a Tesla Solar Roof solution + inverter might cost perhaps 20% more than a regular roof, but the electricity is outside (a free extra) in this math. Better thermal isolation another free plus.
In that scenario I'm assuming people will at least blanket the sunny side of their roofs 100% with PV tiles and only use the non PV tiles on the sides that would produce very little electricity. This obviously would require a big inverter, but that's about it.
Assuming a state where over producing generate checks from the utility to the owner, even at 5 cents/kWh this alone might pay for those 20% extra. Even if you don't get paid a cent for over producing, just the electricity savings could pay for itself in a year or two, over 30 years the entire roof *could* be entirely paid from the electricity produced.
*IF* this turns out to be true, it could actually be the solar revolution we've been waiting for where utilities will be forced to replace their peaking plants with big batteries, in 20 years the USA electricity could be over 50% solar, replacing most coal/natural gas. And places like Hawaii, solar+powerwall will become standard and the grid will collapse if they don't become mostly a interconnected battery.

The other reason I think blanketing the sunny side of your roof with PV tiles is every photon you convert to electricity means a little bit cooler roof or less AC needed when its hot. Even when its cold better get electrons for that heat pump than direct heating.

The simple fact Tesla will take another full year until volume production tells me not even they know exactly how much this will cost.
Can somebody that built a new house less than a decade ago tell me how much their roofs alone did cost ?

Most speculation of how much this will cost is extremely unlikely to predict anything at this point.

 

[RadicalIgnorant]

About the cost sounds like everyone is missing one point: profit margin.

Let's assume Elon is Wizard of Ozz and he can make this roof for $100/square.
Is it better to sell it initially for $1000 an invest in new production or sell it for $150 and grow slowly?
Both for business and Earth first option is better.
So one can be right assuming how much they can cost and be very wrong guessing how much they will cost.
Like with Tesla - initial customers pay premium for changing the world to better place. They are the ones who can afford that.

 

[number12]

About the cost sounds like everyone is missing one point: profit margin.

Let's assume Elon is Wizard of Ozz and he can make this roof for $100/square.
Is it better to sell it initially for $1000 an invest in new production or sell it for $150 and grow slowly?
Both for business and Earth first option is better.
So one can be right assuming how much they can cost and be very wrong guessing how much they will cost.
Like with Tesla - initial customers pay premium for changing the world to better place. They are the ones who can afford that.

How this point is missed by everyone about everything tesla is beyond me. If they can they will (especially when a public company)

 

[neroden]

I think your skepticism is well placed. That price range would work out to $225 to $375 per square, which is roughly equal to materials-only cost of concrete tiles or terra cotta, products with no electrical capabilities.

Aha. Given Musk's claim about "as cheap as a regular roof", I'm betting that's the materials-only cost of the tiles, not the installation-inclusive cost.

Anyway thanks to all of you for very useful information in this thread.

 

[zdre]

The savings vary greatly depending on the cost of electricity in your region and your consumption.
Here is my wild guess for a 2500 sqft roof:
Assumptions: 2000 sqft single story 3br house, Midwest, natural gas air and water heaters.
Roof Assumption:10kW solar roof

Cost of shingle roof (very high estimate): $20,000
Electricity savings per year: $1250 (12¢/kWh average)
Savings in 20 years: $25,000
For the purpose if this estimate, assume loan interest cancels out increase in savings due to inflation.

Cost of solar roof: $45,000
Please feel free to tear this apart.

I was spot on according to the estimator (with tax credit included) :

Cost of roof - $58,500
Tax credit +$12,600
Upfront cost: $45,900

Value of energy (30 years) + $40,600
Net cost over 30 years $5,300

 

[SageBrush]

I used the Tesla estimator, my local utility bill and PVWatts data to estimate the tile PV efficiency. Starting from 100% of a PV tile can collect sunlight, it works out to 10.7% efficiency. If only 80% of tile collects sunlight the tile efficiency is 13.375%

 

[mikevbf]

Musk first said the cost of the solar roof would be less than the cost of a regular roof even before energy production/savings were taken into account:
“It’s looking quite promising that a solar roof actually cost less than normal roof before you even take the value of electricity into account. So the basic proposition would be ‘Would you like a roof that looks better than a normal roof, last twice as long, cost less and by the way generates electricity’ why would you get anything else.”

But in the Ted talk he stumbles and stutters before saying the cost of the solar roof tiles will be cheaper only after taking into the energy produced by the solar panels. Go to about 23:50:
The future we're building -- and boring

I guess as a company Tesla decided between the time they introduced the panels and when they released their actual price, they wanted a higher margin.

 

[MacGreiner]

Musk first said the cost of the solar roof would be less than the cost of a regular roof even before energy production/savings were taken into account:
“It’s looking quite promising that a solar roof actually cost less than normal roof before you even take the value of electricity into account. So the basic proposition would be ‘Would you like a roof that looks better than a normal roof, last twice as long, cost less and by the way generates electricity’ why would you get anything else.”

This was my understanding. I wonder what changed?