8 alternatives to the Tesla Solar Roof (updated)
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.
Solar shingles or solar tiles are a class of photovoltaics that are broadly known as building integrated photovoltaics (BIPV). They are photovoltaic modules that are made to mimic the look of normal roofing products, like asphalt shingles or slate tiles.
They are a small niche of the overall home solar market, but got a prominent boost when Tesla introduced their Solar Roof. While Tesla was not the first manufacturer to enter the market, they were innovators by creating a glass-faced solar tile that looks more like a conventional roofing product and comes in a wider range of styles than other solar shingles available on the market.
Tesla has a rabid social media following, and any new Tesla products instantly go viral. The Solar Roof was no exception, and its entry into the BIPV market has spurred a lot of interest in the segment. Some companies already had solar shingle products, while other companies 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. While the idea of a roof that looks completely ordinary but is capable of discreetly generating several kilowatts of power is appealing, this type of photovoltaics has some serious drawbacks that the consumers should know about. I’ll discuss those issues later in this article.
Better looking conventional solar panels that are an alternative to solar shingles
Because of these drawbacks, I’ll list several alternatives to solar shingles that use conventional solar technology. These aren’t solar panels that try to mimic roofing shingles, but manufacturers take steps to make them look more sleek and attractive than regular panels.
But let’s start off with our review of eight BIPV products.
The Tesla Solar Roof (updated)
Announced to much fanfare in October 2016, Tesla’s Solar Roof product has been slow to reach the market, trickling out to only a few customers in California. Tesla began taking orders in 2017 and reportedly sold out a year’s worth of production from their Buffalo, NY factory in a few weeks.
However, a Reuters story on May 15, 2019 disputes this, stating instead that the majority of the solar cells being produced in Buffalo by their manufacturing partner Panasonic are being exported overseas instead of used for Telsa’s Solar Roof. The story also claims that only a total of 21 installations have been made in California.
The Reuters story isn’t clear about what type of cells are being exported, and whether they are the same ones intended for use in the Tesla solar shingles. In fact, Elon Musk has acknowledged in tweets that technical difficulties with the Solar Roof have slowed delivery to the market. He also addressed this in Tesla’s 2019 Q1 earnings call, acknowledging that Tesla’s energy division took a back seat while the company’s resources were focused on ramping up their Model 3 vehicle production. Now that the company has seemingly survived the “production hell” of the Model 3, Musk stated in the earnings call that 2019 would be the year of the solar roof.
If the Reuters story is true that most cells are being exported, that’s not necessarily a death knell for the Solar Roof as some media reports have stated. Building integrated photovoltatics, like solar shingles, are a complicated product that differ entirely from conventional solar modules in terms of wiring, electronics, materials engineering, assembly and manufacturing. The solar cell is only one component of the overall product. It remains to be seen whether Tesla can actually bring this product to market, but I do think that it’s premature to say that the product is dead.
In any case, they have another deadline they are running up against. Tesla has a deal with New York State, which incentived Tesla to the tune of $750 million to build out the Buffalo factory. According to the Buffalo News, the factory currently employs about 700 people, but its deal with New York state requires it to directly employ 1,460 people by April 2020 or be slapped with a $41 million annual penalty.
If you’re interested in the Tesla Solar Roof and haven’t seen it already, definitely take 19 minutes to watch the 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:
That’s the textured glass tile, which also comes in a smooth version. Here’s what the slate and clay tiles look like:
Not every tile incorporates solar cells. Each design includes tiles with and without solar cells. Tesla explains that, just like any standard solar photovoltaic system, they will size your system so that it generates no more than 100% of your average annual electricity use. The rest of the roof is covered with non-PV tiles so that the roof has a consistent appearance.
Tesla Solar Roof pricing
As Tesla explains, the Solar Roof installation involves tearing the roof down to the sheathing, so this is something you probably only want to do if you roof is already in need of replacement. A per-tile cost isn’t listed on the website. They do give an approximate total cost (materials and labor) of $21.85 per square foot, which they claim is cheaper than a non-solar slate or clay roof, and somewhat more expensive than asphalt shingles.
One Solar Roof customer in California gave some more specific numbers: a roof replacement with a conventional PV system added on top would have cost him $70,000 before incentives, while a Solar Roof with three Powerwall batteries cost him $100,000. Given that the price of three Powerwalls is $21,200, this means that the Solar Roof cost him $8,800 more than a conventional roof tearoff and standard PV installation.
If this price holds true, that could be considered a pretty cost-effective solution in the long run. The tiles are warrantied to last as long as your house. This means that if your attic is ventilated properly so that rot doesn’t set in on the sheathing, this roof could be your last one you need to install.
Be aware that the infinite warranty covers the glass, but not the solar cells, which come with a 30 year power warranty - which is still very good.
From a cost point of view, the delayed delivery is an important consideration because the federal tax rebate drops from 30% to 26% in 2020. This means that waiting for Tesla to get through its backlogged orders will likely mean that you will miss the 30% rebate, resulting in a higher total cost.
Still, if appearance is paramount and the warranty is attractive, you might decide the wait is worth it.
Update: the website Electrek obtained a copy of a Tesla Solar Roof proposal. For a 9.45 kW system, the Tesla Roof will cost about $65,000. This is extremely high if you look at this as a standalone solar photovoltaic system, but the cost does become more attractive if you consider the cost of doing a roof replacement at the same time, which is part of this Telsa solar installation. Even so, the price is high even when comparing to a convetional system with premium solar panels.
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 attractive as the Solar Roof, nor is it offered in a variety of appearances that mimic conventional high end roofing products like slate. Still, the Apollo tiles are undeniably more atractive than a standard solar module. 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 it appears to be quite smoothly integrated into the roof. The installation video below gives a closeup look.
Each product is approximately 47 inches by 17 inches in size, has an STC rating of 63 watts, and a PTC rating of 53.5 watts. Both utilize monocrystalline cells.
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.
Apollo II pricing
Current pricing isn’t advertised, but you can find discontinued Apollo tile products for sale online. One site lists them at $178 per tile. If their current products are about the same price, this would translate to a price per watt of $2.82. For comparison, conventional premium monocrystalline panels cost start around $1.50 per watt, so you are paying about double the cost of a premium solar module, and even more in comparision to a budget solar module.
On the other hand, if you are doing a roof replacement anyway, using the CertainTeed Apollo II Tile does mean you have to purchase fewer conventional shingles for your roof, which reduces that cost somewhat. However, unlike the Tesla Solar Roof, the Apollo II Tile does not have non-solar shingles in the product lineup, so you will still need to install standard materials on the non-solar areas of your rooftop.
The Apollo II shingles are rated to a mechanical load of 250 pounds per square foot, which means they should be able to withstand severe storms and hail. Both Apollo II products come with a 25 year power warranty and a 10 year product warranty.
CertainTeed is owned by the giant French multinational Saint-Gobain, which means there are pretty good odds that the company will be around in a couple decades to provide warranty service if you need it.
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.
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.
Luma is a privately held company, so financial information about the health of the company isn’t readily available.
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.
Similar to the CertainTeed Apollo II Tile, POWERHOUSE is a roofing shingle that takes the place of a conventional asphalt shingle. RGS claims a cell efficiency of 17.1%. The dimensions of one shingle is 41.6” x 31.5”, and each generates 60 watts. This is the STC rating. RGS doesn’t provide a PTC or NOTC rating on their spec sheet.
The POWERHOUSE comes in one style, which is an all-black appearance similar to the Apollo II Tile. The solar cells are clearly visible when viewed from above, but are not apparent when viewed from street level.
They are nailed into place like a traditional single and use proprietary connectors and a racking system that frames the shingles in place and provides a conduit for the wiring system.
The video below gives good closeup view of the shingles and the installation process.
These shingles come with a 24 power production warranty and an 11 year product workmanship warranty.
Pricing is difficult to come by. They did publish a press release that claims the installed cost for a 6 kW system is $3.30 per watt, including labor and materials. They also recommend that POWERHOUSE should be installed with a new roof at the same time.
Is the POWERHOUSE a product we would recommend? If you read our guide on solar panel specifications, you’ll know that one of the important things when evaluating warranties is predicting whether the company will be in business a decade or two decades from now to actually provide service and replacement parts. RGS Energy is a publicly-listed company, and their financial statements indicate a significant net loss for at least four years running.
RGS used to be a high-flying stock that has lost nearly 100% of its market value, and was delisted from Nasdaq. The company is currently exploring “strategic alternatives”, has exited its traditional solar business, and is betting its future on the prospect that California’s mandate that new homes must include solar will boost it’s POWERHOUSE product.
Because of this, we think it would be risky to install this product on your home. If you do go ahead, it would be a good idea to stockpile some extra shingles in case the company goes under and isn’t around to provide replacements.
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.
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.
These panels come with a 25 year power warranty and a 10 year product warranty. SunTegra is a private company, so no company financials are available.
This is a list of other solar roofing products that are either still in development, or are not yet readily available in the United States.
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 availabe in a range of colors. X-Roof is available now, while X-Tile is expected to be available in the fall of 2019.
You can visit their website (in Dutch) to learn more: https://exasun.com/bestellen/zonnepanelen/x-roof/
Forward is a startup that used a Kickstarter campaign to develop their solar roofing project. Similar to the Tesla Solar Roof, the Forward line 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. Like Tesla, customers can make a reservation for $1,000. No word about when the product will hit the market. https://www.forwardsolarroofing.com/
Hanergy is a San Francisco-based company that specializes in thin-film solar. Their Hantile product mimics a dark terracotta roofing tile, and integrates thin film PV. Not much information is available at this time. Their website is: https://www.hanergyamerica.com/hantile
Sunflare announced a prototype of a solar shingle based on thin-film PV. Apart from some mockup images, no product information is available at this time.
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.
- (Probably) 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
- They cost a lot more. Clear pricing is hard to come by, but you should expect to pay at least twice as much on a per-watt basis compared to a conventional premium solar module. The one case where it may make more financial sense to use a solar shingle is when you need to do a complete roof replacement already.
- 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 that 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 because the connectors will be incompatible. 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.
- Product delay may mean higher cost. Because many of these products are still in development, you may miss the 30% federal tax credit this year and receive only the 26% credit that will be available in 2020.
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 better aesthetics, but if you’re willing to consider conventional solar panels, there are choices that look a lot better and sleeker than standard panels. Depending on the color and style of your roof, they won’t stand out as much from the street.
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.
Here’s a guide to these products, starting with an explanation of the technology.
Three major reasons why solar panels look different
Let’s go into some background information about what makes some solar cells look different from others. There are three major design aspects to a solar panel that affect its appearance:
- Whether polycrystalline or monocrystalline silicon is used
- The color of the layer that the silicon cells are mounted to, known as the backsheet
- The color of the frame, or whether the panel is frameless
We’ll take a look at each of these in-depth.
Color differences between monocrystalline and polycrystalline cells
There are two types of silicon cells that you will find in solar panels for the residential market: monocrystalline and polycrystalline. You can read our guide to understanding solar panel specifications to learn more about the advantages and disadvantages of the two types, but when it comes to appearances, polycrystalline cells tend to have a blue color and are often iridescent.
Monocrystalline cells, on the other hand, usually have a very dark or black appearance. Instead of iridescence, they have an even color because monocrystalline cells are cut from a single, continuous crystal of silicon, while polycrystalline silicon is made from blocks formed from smaller grains of silicon.
This difference in color is one factor that may sway your decision between mono and poly panels. Keep in mind that other design factors cause panels to look different, such as the color of the backsheet, how prominent the wires between the cells are, and the type and color of the frame – but the color of the cells is the biggest factor in the overall appearance of a panel.
To illustrate this, take a look at two different panels from Jinko Solar. Their Eagle line comes in mono and polycrystalline models, and the only difference between them is the use of monocrystalline in their Eagle PERC line, and polycrystalline in their standard Eagle.
If you have asphalt shingles, which is the most common type of roofing material used in the United States, the darker color of the monocrystalline panel will probably blend in better with the color of the roof.
Keep in mind that monocrystalline cells are also more efficient, generating more electricity in the same square footage. You pay a higher price tag for this, though.
The effect of the backsheet on solar panel appearance
You’ll notice with the Eagle panels that a white grid is visible in both the poly and mono panels. That grid is there because each panel is made up of 60 individual solar cells that are wired together and mounted on a layer called the backsheet.
The backsheet of a solar module is usually white for a couple reasons. One, the lighter color reflects light, which helps to keep the panel a little bit cooler, improving power efficiency. Also, some of that reflected light can make it back to the surface of the cells, again adding a little bit of power gain.
However, that white grid does draw attention to itself. To make that grid disappear, many manufacturers sell panels with black backsheets. When combined with black mono cells and a black frame, you can have a photovoltaic system that looks like a continuous slab of black. If you have a dark roofing material on your house, these all-black solar panels can blend into the roof very nicely.
However, the tradeoff for going with a black backsheet is a small loss of efficiency.
For example, the NeON 2 line of solar panels from LG is offered in both a white and a black backsheet. Both use monocrystalline silicon, giving them a cell color that is nearly pure black, but the black backsheet of the NeON 2 Black makes the panel uniformly dark. The standard NeON 2 line is offered in panel efficiencies up to 19.6%, but the Black line only goes up to 18.7%. This ends up being only a 15 watt difference per panel, which really isn’t very much power. For many people, the improved appearance is well worth it.
It’s also worth noting that some panels eliminate the gap between cells, giving you a continuous field of color regardless of what the color of the backsheet is. An example of this is the Sunergy DMWA1. You can see an image of it below.
Framed and frameless solar panels
The last consideration is the color of the frame, or whether the panel even has a frame at all.
Conventional solar panels are made of several layers held together with an aluminum frame, which is typically silver or black. This is an important detail, because even if you choose a mono panel because of its dark color, the manufacturer still might pair it with a light colored frame, which may not be what you want.
For example, look at the Jinko Eagle panel above, which uses mono cells but has a silver colored frame. Compare that to the LG NeON 2 series, which also uses dark mono cells but instead has a black frame. If the appearance of the panel is important to you, this is another detail to pay attention to.
Frameless solar panels
However, some panels forgo the frame completely. These are called frameless solar modules, and are held together in a sandwich either between glass and a sturdy backsheet, or with glass on both the front and back (known as glass-on-glass).
Glass-on-glass frameless models can even use clear backsheet, which results in a panel that is transparent between the individual cells of the module. This makes for a pretty unique look. This type of panel is usually marketed for special applications, such as awnings, carports, and greenhouses.
This opens up design possibilities that wouldn’t look nearly as pleasing with conventional framed panels.
However, frameless panels aren’t widely deployed yet in the residential solar market. The main reason is that they don’t use conventional racking systems, which limits your choices when it comes to installation. Companies that do make frameless panels, such as Lumos Solar, sometimes also develop custom mounting solutions, but that means you’re tied to a proprietary product. However, if you’re looking to do something unique, such as a back porch awning that also generates electricity, the tradeoff may be worth it.
It’s certainly also possible to use frameless clear glass-on-glass panels on a rooftop, and this can look great. The main issue would be finding a compatible mounting system, which is something your solar installer can advise you on.
Choices for all-black and frameless solar panels
For the homeowner who wants to go solar and have their photovoltaic system look as good as possible, the good news is that there are a lot of alternatives. Solar shingles are one choice, but going with conventional panels have a lot of advantages.
Below are a list of some companies selling all-black and frameless solar panels.
Black solar panels
Here’s a partial list of companies and their models of dark solar panels. In some cases, there are two models listed, such as Hanwha, which offers both the Q.PEAK and Q.PEAK DUO in a black model.
One thing you’ll notice with some of the product images is that even though these all use dark monocrystalline cells and dark frames, many still have a faint pattern over top of the cells. These are wires called busbars, and they carry electric current from the cells. Companies use different busbar counts and widths, which is why you see different patterns among these manufacturers.
One exception is SunPower, which actually has found a way to place the wiring on the backside of the solar cell. The result is a solar panel that is a very pure black.
|Hanwha Q CELLS||Q.PEAK DUO BLK-G5|
|LG||NeON 2 Black|
|Solarworld||Sunmodule Plus Mono Black|
|Trina Solar||ALLMAX M PLUS|
Frameless solar panels
The list of companies offering frameless solar panels is much smaller. It’s simply a niche product, and so the market for this category is quite small. Still, there are some choices, including products from Canadian Solar and Trina Solar, which are two of the largest solar manufacturers.
Given that the list of cons is much longer than the list of benefits, we think that solar shingles are a poor choice at this time for the majority of people. There’s a lot of risk in going with a proprietary technology, a lot of these products are unproven, and pricing is very high.
This could change. Of all the products on the market, the Tesla Solar Roof appears to be the best choice due to the wider range of options and very robust warranty. Unfortunately, its not widely available on the market, making it difficult to evaluate properly. Given the big interest in this product, we’ll be sure to update this article when we know more.
Working with your solar installer
If you’re ready to make the leap and go solar, it’s really important to make it clear to your solar installer that aesthetics are important to you. This is why it’s a very good idea to work with installers who actually come to your house and meet you in person, rather than simply give you a quote over the phone or online.
The installers than The Solar Nerd work with all offer this type of personal service. If you’re ready to go solar now, fill out our form to get started.