Alternatives to the Tesla Solar Roof (updated 2021)

A review of current and upcoming solar shingle products, and we see where Tesla is at with their Solar Roof. Also: great conventional alternatives to solar shingles.

Photo of six different examples of solar shingles.

Are you interested in home solar panels but think they’re ugly? Some people think that solar panels can look pretty cool, but there’s no doubt that conventional solar panels draw attention to themselves, which may not be something you want for your home.

While you can take steps to improve the curb appeal of solar panels, some homeowners simply don’t like their look no matter how sleek and professional a job the installer does.

If this describes you, solar shingles (also known as solar tiles) might be the product for you. Solar shingles come in shapes and colors to mimic conventional roofing products, but they have solar cells embedded in them which means that you can have a quite normal-looking roof that generates kilowatts of electricity.

Solar shingles are only a small niche of the overall home solar market, but consumer interest spiked when Tesla introduced their Solar Roof. Tesla was not the first company to enter the market, but they are the largest. They were innovators by creating a glass-faced solar tile that is a complete roof replacement

Tesla has a rabid following, and new Tesla products instantly go viral. The Solar Roof was no exception, and its entry into the market spurred a lot of interest in solar shingles. Some companies already had solar shingle products, while others were seemingly inspired by Tesla to develop competing products.

In this article, we’ll take a look at the current offerings from Tesla and competing manufacturers, and discuss the general pros and cons of going with solar shingles instead of conventional panels. While the idea of a roof that looks completely ordinary but is capable of generating several kilowatts of power is appealing, this type of solar has some serious drawbacks that consumers should know about.

The Tesla Solar Roof (version 3)

The Tesla Solar Roof is a full roof replacement with glass tiles that look like normal roofing shingles or tiles, but have solar cells and electronics embedded in them.

If you’re interested in the Tesla Solar Roof and haven’t seen it already, definitely take the 19 minutes to watch the original product unveiling by Elon Musk. As he explains, the Solar Roof is a glass-faced solar tile that uses hydrographic printing to give the tile an appearance that looks remarkably like slate, clay tile, or a dark shingle. The glass layer encorporates louvers that permit light to enter the tile from above, but when viewed at an angle (like you would from street level) the louver presents a different appearance that reveals the printed design.

The result is striking. If you weren’t told, you probably wouldn’t realize that the roof is actually covered in solar panels. The solar cell isn’t visible unless you’re looking directly at the tile from above, and even then it’s not that obvious, although it’s a little more visible in the “clay” version. Here’s some images from an early customer:

Telsa solar roof.  Credit: Amanda Tobler
Credit: Amanda Tobler

While the original launch video shows the slate and clay tile designs, Telsa is currently only installing the Textured Glass version that you see above. It’s not clear whether the other styles have been dropped in Version 3 or they will be released later.

Not every tile in a Solar Roof incorporates solar cells. Some tiles are just glass, allowing the roof to be uniformly covered with identical looking tiles without the need for the more expensive solar tiles to be used everywhere. Tesla explains that, just like with any standard solar photovoltaic system, they will size your system so that it generates no more than 100% of your average annual electricity use.

Underneath each tile is the electronics, wiring, and an air gap for ventilation.

Tesla Solar Roof specifications

As of February 2021, these are the published specifications for the Solar Roof:

  • Tile warranty: 25 years
  • Power warranty: 25 years
  • Weatherization warranty: 25 years
  • Wind rating: ASTM D3161 Class F
  • Fire rating: Class A (highest rating)
  • Hail rating: ANSI FM 4473 Class 3
  • Roof pitch: 2:12 to 20:12
  • Inverter power: 3.8kW / 7.6kW
  • Inverter: 97.5% efficiency
  • Inverter dimensions: 26" x 16" x 6"
  • Inverter warranty: 12.5 years

Some thoughts about this: the tile warranty is similar to other high performance solar panels with 25 year warranties such as LG and SunPower. The warranty also includes labor.

The inverter described is a central inverter similar to those offered by SolarEdge and SMA. Its warranty length is similar to a central inverter, which is half the duration of the 25 year warranty offered with Enphase microinverters (the current market leader for microinverters). No word about how much an inverter replacement would cost.

Solar Roof availability

While the promise of the Solar Roof is great, the reality of bringing the product to market has been a challenge for Tesla. In June 2020, Tesla started cancelling orders and returning customer deposits, in some cases three years after the customers put down a $1,000 deposit.

Tesla sent a notice to some customers that they were not in their service area:

Upon further review, your home is not located within our currently planned service territory. The driving distance from our closest warehouse would make it difficult for us to provide you the high-quality service that our customers deserve. For this reason, we will not be able to proceed with your project.

The fact that these notices were sent out, in some cases, years after customer deposits were taken shows how difficult it has been for Tesla to scale up their solar business since taking it over from SolarCity.

While some installations have happened, deployments are still limited. That said, production is starting to ramp up at the Buffalo factory, although this has been hampered by the pandemic. According to the Buffalo News, production of the solar roof in Buffalo reached 4 megawatts per week until the factory was forced to pause due to the pandemic.

Version 3 product release

Version 1 of the Roof was announced in October 2016, but it had very limited production. On a Tesla earnings call in March, Elon Musk explained that the solar division had taken a back seat to the Model 3 vehicle production ramp-up, which consumed the company’s focus for over a year. With Model 3 production improving, Musk declared that 2019 would be the year of the solar roof.

More recently, on a conference call on October 25th 2019, Tesla announced the latest version of their Solar Roof.

It turns out that Tesla is currently on their third version of the Solar Roof and that the previous two versions were expensive and complicated to manufacture and install.

The following are some questions and excerpts from the conference call. It has been lightly edited.

Solar Roof conference call: introductory remarks by Elon Musk

The following are some excerpts from Musk’s introduction. You can follow the link above to hear the entire call.

Musk spends time explaining the improved economics of the version 3 roof, but that the Solar Roof still only makes sense if you are planning to replace your roof anyway. If your roof has ten years or more life left in it, he recommends that you go with conventional Tesla solar panels:

The intent behind the solar glass roof is that we can make a roof come alive. All of these rooftops are gathering sunlight, but doing nothing with it... In the future, it will be odd for roofs to be dormant.

...The solar glass roof is not going to make financial sense for somebody who has a relatively new roof, because this itself is a roof that has integrated solar power generation. Therefore, it has the cost of roofing a house in addition to the cost of solar cells. However, we've been able to achieve with Version 3 a price point that is less than what the average roof costs plus solar panels. So if you're looking at two options: one is you need a roof, or need to re-roof your house, and look at the cost of that and the cost of adding solar panels to that roof, versus the cost of Tesla solar glass roof, which is a roof plus integrated solar cells, the Tesla solar glass roof will cost less.

...It’s been quite hard to get to this point. This is quite a difficult product because roofs have to last for a long time, and when you add electrification to the roof, and then you have wires, you have to make sure that’s going to be safe, and not cause any risk to the house. You want this to last something on the order of 30 years or more - it’s not easy to do accelerated life testing, in course of 6 months try to accelerate the life of the roof such that we know what it will be like in 30 years.

...In a nutshell, if you are re-roofing or getting a new roof, I feel quite confident that this is a smart move. But if your roof is already new, then it will not be a smart move financially. You may still want to do it, but it will be financially punative to do it on an existing roof that has a lot of life left on it, then we would recommend the Tesla solar panels.

What changes have been implemented from v1 to v2 to v3, and what was the impact on cost and performance?

We increased the size of the tile, increased the power density, decreased the number of parts and subassemblies in the tile by more than a half. This goes in the direction of lower cost and easier manufacturability. The technology used to hide the solar cells behind the glass has been improved. You want the photons form the sun to get to the cell, but not be asetheically unappealing. Solar cells are optically isotropic - they can look green from one angle and purple from another. We have, through a number of iterations, landed on a technology that gets the solar tiles to the point where they are anisotropic - they blend in with non-solar tiles and look the same from any angle.

The other key aspect was focusing on installation. We really wanted to achieve an installation time that was faster than a new roof plus traditional panels... With the right tooling and equipment, and especially paying close attention to the edge effects of where multiple planes of the roof meet... I think we can actually have the solar glass roof install faster than a comp (composite) shingle. That’s the target. We’re coming after you, comp shingle!

The final thing I would mention is the flashing - the trimming of the roof - in early versions of the product were almost like custom handicraft. What we’ve done is come up with beautiful solutions that are achieveable in the field.

Our installers have been working hard installing this, and have already seen this is much simpler, faster, and a lot more intuitive to install.

When can we expect Solar Roof v3 to available for wide residential adoption?

That’s now, actually. You can go to the website, enter your address, and place an order right now. We’re ramping up installations as fast as we possibly can, starting in the next few weeks. Actually some are underway right now. Our goal is to get north of 1,000 roofs per week as quickly as possible. It's always hard to predict the early stages of a production ramp because things move as fast as the slowest item, but I think over the next several months we’ll pass 1,000 roofs per week. That’s our goal.

What is the current solar roof production capacity, and how should we think about the production ramp through 2020? How are you feeling about demand?

I don’t think we’re going to have much of a demand problem, to be honest. I think demand will be in far excess of supply. As always, it’s very difficult to predict a production ramp because it almost always looks like an S-curve. It starts off very slow at first because of a number of constraints. It could be a very trivial part that is limiting the production ramp. Just one little thing that is taking longer that expected - that’s the total production rate. It’s essentially impossible to predict with accuracy the fast moving part of the production s-curve, but we can predict when the s-curve starts to flatten out - that’s much more predictable. And that's why I think probably several months from now, we’ll be able to do more than 1,000 roofs a week.

Long term, we obviously want to do 10,000 roofs a week, and then 20,000 roofs a week. The addressable market here is something on the order of 100,000,000 houses worldwide.

We're starting off with the textured black glass, and hopefully we'll be able to bring to production other variants of the solar glass roof every six to nine months - something like that. One of the most challenging is achieving a good earth tone solar glass roof - meaning a good clay tile. It’s doable, but it’s harder to achieve the right look. But that’s something on the order of a year away - something like that.

How will Tesla handle logistics with installations? Do you already have partnerships with installation companies?

We don’t have any partnerships with installation companies. The current plan is to iron out the broad brushstrokes with our internal installation crews, so we feel like we’re getting a positive learning curve, and then bring in outside roofing companies and asking, how can you help us make this better? I think we'll see a very rapid improvement with the solar roof installation and timing. Version 3 is the first version that we think that should be ramped up at scale. This is often true of new technologies. Windows 1 and 2 didn't really work, frankly. Windows 3 was the first big one.

We’re going to keep improving the roof as we scale. We’re hiring a lot of installers. We'll be partnering with installation companies in weeks to come.

Can you speak about the relative improvement in cost from Version 2 to Version 3 of the solar glass roof?

You’re right, Version 2 was too expensive. It’s not like we were making a ton of money on it - we were just trying to not lose money on it. It just wasn’t a version that was worth scaling because it was too expensive. Version 3 is something where we do think we can get below the average roof cost plus retrofit solar panels.

What do you anticipate the wait time will be?

It depends on how many people sign up for the glass roof. It might be a few months they'll have to wait, or several months. The sooner they sign up the less time they'll have to wait. We will grow this exponentially. It might be doubling every month - something like that. We want to go to the point next year where there's a very short wait time.

Tesla Solar Roof pricing

As Tesla explains, the Solar Roof installation involves a complete roof replacement, and makes the most financial sense if you happen to need a new roof.

Version 3 of the roof is substantially cheaper than previous versions. A story by Electrek says that the Version 3 price is 40% cheaper. In their example, a 9.45 kW Tesla Solar Roof installation that includes a Powerwall battery was quoted as $38,266. This is substantially better than previous price of $64,634.

The Solar Roof comes with an infinite warranty on the glass, but not the solar cells, which come with a 25 year warranty.

With the promised ramp-up in production, if you put in an order today you might be able to get your installation done as quickly as a couple months, but as you can read in the conference call transcript, there’s a lot of uncertainty in how fast they’ll be able to produce it.

Still, if appearance is paramount and the warranty is attractive, you might decide the wait is worth it.

Solar Roof pricing estimator

If you go to the Tesla website, you can plug in your street address and get a rough custom price estimate. The online estimator uses satellite images to automatically estimate your roof area, and your monthly electricity cost to estimate how many panels you’ll need.

A Tesla Solar Roof price estimate for my home
A Tesla Solar Roof price estimate for my home

Be aware that you should toggle the “show incentives” button to see the gross price of the system. As you can see, my quoted system is $22,380 before incentives. For comparison, my 18 panel 4.6 kW system cost me $18,000 before incentives in 2013. If I bought a conventional solar system today, the price would be quite a bit lower.

HomeAdvisor estimates that a roof replacement costs an average of $7,777 nationally.

If you’re thinking of a premium roofing product, the Tesla Solar Roof should be on your radar. However, you should also recognize that a premium, non-solar roof such as slate or metal should last at least 50 years, if not more. Because the Solar Roof is warrantied for 25 years, it’s possible that the roof will be dead after 25 years and you’ll need another replacement if you want to continue with solar.

Tesla Solar Roof: pros and cons

There’s no doubt that the Tesla Solar Roof is a unique, great-looking product. If you’re in a situation where your solar panels would affect the curb appeal of your home (because its southerly orientation faces the street), the Solar Roof could be a great solution. Also, if your roof needs replacement anyway, the cost of the Solar Roof may be similar or a few thousand dollar premium over a new roof and conventional panels.

The main downside at this point is limited availability, and the higher risk of going with new proprietary technology. With conventional solar panels, any qualified solar installer could provide service and replacement parts. Not so with Tesla.

Still, if you really want solar shingles, the Telsa Solar Roof is really the only product that can be recommended.

Solar shingles available from other manufacturers

CertainTeed Apollo II

CertainTeed is a North American company that manufactures products for roofing, insulation, wallboard, and more. They have two solar products under their Apollo line: Apollo II is a shingle that lays on top of your existing roof, while the Apollo II Tile is a replacement tile, similar to the Tesla Solar Roof.

Unlike Tesla, CertainTeed doesn’t use glass louvers or hyrdographic printing, so the product isn’t as sleek as the Solar Roof. Still, the Apollo tiles do integrate more seamlessly into a roof than standard solar modules. The Apollo II product sits flush on top of your existing roof. Unlike a solar panel where there are several inches of air space between the back of the panel and the roof, the Apollo II is installed with a proprietary racking system that has a very low profile and flashing that allows you to install your standard roof shingles directly flush with the Apollo shingles so that everything appears to be smoothly integrated. The installation video below gives a closeup look.

Installation video for the CertainTeed Apollo shingles gives a closeup view of the product.

Each tile is approximately 47 inches by 17 inches in size, and uses monocrystalline cells for an STC rating of 63 watts and a PTC rating of 53.5 watts.

How does this compare to a conventional solar module? An average module is about 2500 square inches, and might have a rating of around 280 watts. This translates to a power generation of around 0.112 watts per square inch.

The Apollo shingles are around 800 square inches each, which is 0.079 watts per square inch. This means that they are only about 70% as energy dense as an average performing conventional panel.

Current pricing isn’t advertised on the CertainTeed website, but we found one online retailer selling a package of 5.36 kW Apollo II tiles for $14,395. That doesn’t include installation or an inverter. That’s roughly twice the price of premium conventional solar panels, making them very expensive - significantly more expensive than the Telsa Solar Roof.

Luma Solar Roof

Luma Solar offers a complete roof replacement product that is simply called the Solar Roof. Similiar to Telsa, this is a complete solar roof replacement product that includes both non-solar and solar cell components that gives the roof a more uniform appearance than the solar-only shingles offered by RGS and CertainTeed.

They also offer their PV shingles as a standalone product that can be mixed with conventional roof shingles, similar to those from RGS and CertainTeed. Each shingle is 54.37" x 15.62" and uses polycrystalline cells to generate 60 watts. They offer a 25 year power output warranty and 5 year materials and workmanship warranty.

photo of Luma shinglesLuma shingles

Pricing isn’t available on their website, although one online retailer offers a Luma shingle that is listed as discontinued. Their price is $240 for a 60 watt shingle. This translates to $4 per watt, which is at the very high end of pricing for premium modules.

It should be noted that a 5 year product warranty is very short. Budget conventional solar panels come with at least a 10 year product warranty.

SunTegra Tile and Shingle

SunTegra is a New York-based company that provides two products: their Shingle which is mounted on top of your existing asphalt shingles, and their Tile which is pitched as a replacement for concrete tile products. Neither is offered with a non-PV option, so these are intended to be integrated alongside conventional roofing shingles or tiles.

The Shingle is a little different from other solar shingles in that are larger than an asphalt shingle, measuring 52 5/8" x 23 1/8". This is because they sit on top of your roof and do not replace your existing shingles. They are very low profile, measuring only 3/4" high. One feature not seen in other products in the incorporation of an air channel on the backside of the module, which the company claims will keep the panel cooler and improve efficiency.

photo of SunTegra shingles photo of SunTegra Tiles

The panels use monocrystalline cells and have a peak output of 100-110 watts. No PTC or NOCT power rating is listed.

Pricing is not listed on their website.

SunFlare PowerFit 20

Sunflare has an upcoming product called the PowerFit 20. Unlike most solar panels that are based on crystalline silicon, the PowerFit will be based on thin-film technology. Thin-film is sometimes used in a small, portable applications but rarely for rooftop or utility solar farms, with the notable exception being panels from the US company First Solar.

Despite its niche status, thin-film does have promise. Sunflare’s PowerFit is intended specifically for standing seam metal roof, where it will fit neatly between the seams. Take a look at this screenshot from their promotional video:

A Sunflare PowerFit panel being installed.
Sunflare PowerFit panel being installed.

Each panel will be 65 inches long, 14 inches wide and generate 60 watts. The technology used is copper indium gallium selenide, also known as CIGS.

This product is not yet released, but the manufacturer says it’ll be available in May 2021 and encourages prospective customers to sign up on their website for updates.

Other solar shingles that are discontinued, vaporware, or not available in North America.

There have been many companies, small and large, that have tried and failed to bring solar shingles to market. Some of them are listed below.

Exasun X-Tile and X-Roof

Exasun is a company based in the Netherlands. Their X-Roof product is a complete roof replacement, while X-Tile resembles a terracotta tile that will be available in a range of colors. We first heard about these products in 2019, but so far neither seem to be available in North America.

You can visit their website (in Dutch) to learn more.

Forward

Forward is a startup that used a Kickstarter campaign to develop their solar roofing project. Like the Tesla Solar Roof, Forward is intended to be a whole-roof replacement product that includes PV and non-PV components for a seamless visual appearance. They have two styles in development: Metal, which resembles a steel roof, and Tile, which resembles terracotta.

Their website invites customers to make a reservation for $1,000, but in the four years since their Kickstarter campaign launched, there’s still no indication of when the product will be available. They were aiming for installations to start in 2019, but none have happened yet. Perhaps as a further indication that this product may be vaporware, the website doesn’t seem to have been updated since 2019.

Hanergy HanTile

Hanergy is Chinese company that specializes in thin-film solar. Their Hantile solar roofing tile mimics a dark terracotta roofing tile and integrates thin film PV. It looks like they may have some real deployments in Europe and at one point intended to bring the product to market in North America through Hanergy America, but in 2019 Hanergy had mass layoffs. The Hanergy America division appears to be dead, as is any reference to bringing the Hantile product to North America.

RGS POWERHOUSE 3.0

The POWERHOUSE line of solar shingles was originally a Dow Chemical product based on thin-film solar. Dow exited the solar business in 2016 and sold the POWERHOUSE product line to RGS Energy in 2017. RGS changed the solar technology from thin-film to monocrystalline cells and branded it POWERHOUSE 3.0. Here’s a video of what the product looked like:

Unfortunately, in February 2020 RGS Energy filed for bankruptcy. This is a bigger problem than any of the other failed products mentioned above because the POWERHOUSE shingles had some limited market success and found customers for the product. Those customers are now, frankly, screwed if they need warranty service or support.

Pros and cons of solar shingles

It’s clear that there is a lot of consumer interest in photovoltaics that look more attractive than standard photovoltaics, and several companies have stepped up to introduce a range of products into the market. There’s no doubt that some of these products make for a nicer looking roof, but does it make sense to use these in place of conventional solar modules?

Let’s take a look at the pros and cons:

Pros of solar shingles

  • They look better. The Tesla product line is the most impressive looking, but all of these products give you a much cleaner looking roof, one that passsersby might not even notice is different from other roofs on your street. One case where this may be important is if you live in a condo or gated community and have rules under your homeowners association that restricts you from placing solar panels on your roof for esthetic reasons. Keep in mind that California and New York, two of the largest solar markets in the countries, have rules that limit the ability of an HOA to restrict solar panels. There are two dozen states with similiar solar access laws.
  • (Possibly) higher home equity. If the product holds up over time, the investment you’ve made into your home with BIPV panels is significant, and should result in a higher value in your home. My article discussing whether solar panels add value to your home goes into this topic in detail.

Cons of solar shingles

  • Risk. Going with one of these solar shingles is more risky than choosing conventional solar panels. That risk varies between somewhat risky (Telsa) to extremely risky (small companies or a startup). The failure of RGS is a great example of why consumers need to be cautious when selecting one of these products.
  • They cost more. Clear pricing is hard to come by, but in some cases you can expect to pay at least twice as much on a per-watt basis compared to a conventional premium solar module. The Tesla Solar Roof is one case where their solar shingle is close in price to a complete roof replacement with conventional solar panels installed at the same time.
  • Poorer efficiency. Even though some of these products use monocrystalline cells, none of them are as efficient as the best modules on the market, which are nearly 23% efficient. This is partly because of design compromises that prioritize esthetics, and also poorer ventilation compared to a standard rack-mounted module that has several inches underneath to permit airflow.
  • Higher module temperatures. Because these modules sit directly against the roof, these solar shingles will get hotter. This reduces cell efficiency and may also contribute to a shorter lifespan.
  • Proprietary technology. Unlike standard modules, each solar shingle manufacturer has a custom design, mounting system, and electrical connectors. This also means that installation may be non-standard and limit your choice about which company can do the installation - often it will be the manufacturer itself.
  • Risk of tying yourself to one company. Because these products are proprietary, there is a higher risk to you if the company goes bankrupt. If a shingle dies, you likely won’t be able to substitute a product from a different manufacturer. This means that you have be extra careful to select a company that is likely to survive for the next couple of decades.
  • You are limited to a string inverter. None of these products integrate power optimizers or microinverters, which is a serious drawback if your roof has shading issues that could normally be mitigated with a more sophisticated inverter system. This also complicates diagnostics if you have a failure. With a conventional system, if you have a single panel failure, a power optimizer or microinverter will tell you which panel experienced the fault. This won’t be the case with solar shingles, which means that you will need a service call to diagnose any power interruptions. Even if this is covered under a warranty, it’s still a major downside.

Great conventional alternatives to solar shingles

As you can see, the list of drawbacks to BIPV products is significant.

The main reason that homeowners are interested in them is improved aesthetics, but a better alternative for most people is to choose conventional panels that are all-black.

All-black solar panels look sleeker and tend to blend into a roof better. Some manufacturers also offer racking systems with dark frames to match the color of the black panels.

The big benefit of going this route is that you’re using mainstream products, which means you’ll have far more product choices, better known product longevity, conventional racking, more choice of inverters, and many more options when it comes to choosing installers and getting repair service in the future.

For some other tips, read our article on how to improve the curb appeal of solar panels .

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