Solar Panels Vs. Tiles – Apples or Oranges?
Elon’s enthusiasm for the category of solar tiles, sometimes called shingles, has definitely raised interest in residential solar, for which we’re all grateful, but how do they perform when compared to conventional photovoltaic (PV) solar panels?
Let’s look at cost, choice of vendors, and other factors that might help with making an informed choice.
Cost of Panels Vs. Tiles
Solar power system costs will vary widely based on available space, how much power a home needs, but for this example, let’s compare a typical sized installation.
A solar power system size of 6.38kW will cost around $20K to install when using solar panels. Recent studies have shown that the price tag on a 5.57kW system can amount up to $58,000 when opting for solar shingles. That’s an instant upfront cost difference of nearly 200% more.
Whether you’re in the market for a new roof or not, when installing solar shingles you will need to replace your existing roof with a blend of non-solar glass tiles and solar-enabled glass tiles. This elegant product definitely comes with an upsold price. The average cost of a new roof can range from $8,000-$14,000. Even when bundling a brand new roof with your PV solar panel system (which is not typically needed to install solar) you will still get quite the savings, costing an average of $33,778.
Looking beyond upfront costs, one of the main reasons homeowners choose to invest in a solar system is to save money in the long run. The ROI (payback period) for an average solar panel system is 5.15 years. It will take a whopping 19.49 years to see your return when investing in solar shingles, giving solar panels a 74% quicker return on investment than solar shingles. Modules will put you in the black for 10 extra years before the end of your warranty as opposed to shingles.
And final thing to consider around cost is upkeep. Golden Bear’s Solar Installation expert Rob Davy weighs in “Tiles have a 10 year warranty or less compared to 25 years on regular solar panels. Tiles are not as productive due to the material they are made of and the fact that they are nailed down to a roof and there is no air circulation under the tile for cooling. Between overheating and the material they are made of, they just don’t last.”
Who makes Solar Tiles?
Solar Panels are made by hundreds of leading companies; with tiles also called shingles, there are only a few currently known to be entering the market. In addition to Tesla, here are other companies currently promoting, and in some cases, offering options.
Certainteed’s Apollo II (Note: Golden Bear is a Master Certified CertainTeed Installer.)
CertainTeed is an old company with a new name; it was originally (in 1904) General Roofing Manufacturing Company. Now, CertainTeed is a subsidiary of building product company Saint-Gobain, and it specializes not just in roofing but in “siding, fencing, decking, railing, trim, insulation, gypsum, and ceilings,” according to the company website.
One advantage that CertainTeed has on its competitors is that its Apollo II solar shingles have been available for about five years now, and it’s possible to buy said shingles through an installer. Each shingle or tile contains “14 high-efficiency monocrystalline silicon solar cells” that “provide a power rating of 60 watts per solar shingle,” CertainTeed says.
CertainTeed’s product manager is upfront about the fact that his company’s solar shingles are four- to seven-percent less efficient than traditional rack-mounted solar panels because without air circulation under the shingles, the solar cells have to be able to work at higher temperatures (this is common to most solar shingles). (EnergySage says that, according to solar installation data, their cost is approximately $4.90/Watt, compared to $3.14/Watt for an average rack-mounted system and $6.40 for an estimated Tesla installation).
Luma Solar
Luma’s solar roof varies by the complexity of the system. According to their sales director, if a customer just wants a portion of their roof solarized, then it costs about $4.50 per Watt, although an “edge-to-edge” custom solar system can run up to $38 per square foot. Custom roofs take into account the customer’s future energy use, their roof’s sun exposure, and the customer’s overall budget.
Luma also advertises a higher efficiency rate for its solar shingles. The company says that because its patented shingle design allows for airflow underneath the shingle, its system has a 21-percent solar-to-electricity conversion efficiency, which is high even for rack-mounted panels.
Suntegra
In its recent press release, Sunrise Solar stated that it had already installed 55, 105-watt SunTegra shingles on a home in Connecticut one year ago, presumably as a pilot project.
SunTegra’s website says its solar shingles are lightweight and use 50-percent less wiring than rack-mounted solar panels.
RGS’ Powerhouse 3.0
Powerhouse solar shingles were developed by The Dow Chemical Company, which installed early versions of the shingles on approximately 1,000 houses starting in 2011. RGS Energy came on the scene later, becoming the exclusive manufacturer of Powerhouse shingles as well as the warranty servicer for existing homes with the shingles.
The company is still in the process of certifying its shingles for roof installation, and it expects reservations to increase after all necessary certifications have been acquired.
Like the Apollo shingles, the Powerhouse shingles are literally the roof (they’re not pasted flush against asphalt shingles below), and RGS expects that a Powerhouse-shingle-plus-asphalt-roof system will run $4.15 per square foot, including installation.
Powerhouse says its 60-Watt shingles will have an energy conversion efficiency factor of 17.1 percent, which is on par with many rack-mounted solar panels today.
Performance, advantages and disadvantages of solar panels vs. tiles
Although both solar panels and solar shingles will have the same end result of producing solar energy for your home, when closely observing their performance capabilities, it’s like comparing apples and oranges.
A top advantage of using solar panels is the ability to monitor energy generation at a module level. Real time monitoring is a capability that comes in handy. This is a feature that is not available when working with a solar shingle installation.
Another thought to consider is that the average solar panel system will have 22 interconnection points. Solar shingle systems have anywhere from 220 to 660 connection points. Why is this relevant? Think of each point of connection as a potential point of failure during installation and operation. This means your install will have 10 to 30 times more chances for system failure which can lead to lengthier troubleshooting and repair time. A system repair potentially compromises the roof integrity.
The last thing you want to think about when comparing panels and shingles is the affect on other systems in the home – like air conditioning. Because solar shingles rest directly on your roof, since they are the roof, they have been known to generate heat and that hot air which will end up in your attic and heat up your home. This will cause your air conditioner to work harder and lower the overall energy efficiency of your home. To combat this issue, solar panels, since they are not part of the roof, are installed to be lifted off the roof to provide air flow and minimize heat transfer into the home.
Which is better? Solar Panels vs. Solar Tiles
Long story short – your best cost option will be panels, despite some very assertive promotional hype. However, if you are intrigued with the aesthetics and being on the leading edge, there are tile/shingle options that are available now.