Tesla’s Solar Roof Tiles: Worth the Investment?

Both the renewables and tech communities have been abuzz this year about Elon Musk’s company Tesla joining forces with SolarCity, especially with their release of the Solar Roof. If you haven’t already heard, Tesla is releasing PV panels that can replace roof tiles directly, so instead of having panels installed on your roof, the panels would be your roof. It is certainly exciting to see so much attention brought to solar technology- Elon Musk is worshipped by techies, space nerds, and business gurus alike-  but like all new tech bombshells, there are serious risks involved.

Here is our take on the solar roof.

This Technology Isn’t New

Solar roof tiles fall under the category of BIPVs, or building integrated photovoltaics. In other words, the solar cells are incorporated directly into the structure of the building, and therefore are often a more aesthetic choice. This technology has been around for years and has been produced by many large manufacturers, including Dow, Sharp, Kyocera, Sunpower and Suntech. All these manufacturers ventured into the BIPV market but ultimately opted out, as BIPVs have three major flaws: efficiency, price, and maintenance/safety.  
Let’s break these down one by one:

Efficiency is Key

The efficiency of your solar system can mean the difference between a costly investment and a profitable investment. The shape and color of the solar roofing tiles will decrease the efficiency by up to 12%, but what will really impact the output of the system is, ironically, heat. Traditional solar panels are set several inches above the roof for this reason: it allows space for airflow underneath the panels to cool them down. Heat not only decreases panel output but can also seriously damage the system’s wires.

Investing in a Beta Stage Product

It is important to remember that solar is not like other tech markets in which products are quickly replaced. Solar is a long-term investment, and so is the roof over your home. You can’t just run down to Verizon for an upgrade when the iRoof 8 makes its premier. That being said, this first generation of Tesla’s Solar Roof has already sold out on pre-order. It’s quite likely that we will see a 2.0 version come out in the next few years. What if the new version is twice as efficient or a third of the price of the previous model? It’s assumable that Tesla will not exactly have a seamless “upgrade” policy.

Elon Musk has made the claim that his product will be less expensive than redoing your roof and installing solar, but not everyone needs a new roof. Many people are willing to pay the premium for such an attractive product, but it does not pencil out for everybody.

The Roof Over Your Head

Safety and maintenance are our biggest concerns with the Solar Roof product. By using these tiles versus traditional solar panels, you may have thirty times more electrical connections on your roof, and therefore thirty times more points for potential failure and electrical shortages. If these connections are not properly secured, which may very likely be an issue (who is installing these tiles, a roofer or an electrician?), this poses a fire hazard. These installations will require contractors with both electrical and roofing experience, which may not be easy to come by.

Tesla will be using string inverter technology to convert the electric current generated by these tiles, so it will be impossible to monitor output at the panel level. That means if a single tile or group of tiles aren’t working properly, it will be extremely difficult to pinpoint the problem, and it will affect the output of the whole system. Have you ever been hanging holiday lights and one pesky bulb is ruining your whole string? Imagine that feeling when it’s your home’s power source on the line and not your unspoken competition with your neighbors for the best Christmas display.

If something does go wrong, the solution may not be as simple as switching or removing a panel. This is the roof over your head. The potential consequences of these failures are much more serious and could be extremely costly. Tesla is making big promises in terms of warranty, but we get calls all the time about defective solar systems that were installed by a company that is no longer around to honor their warranty. Tesla is a very large and successful company, but anything is possible, especially with its acquisition of SolarCity.  Their track record is far from perfect, just recently they settled to pay $29.5 Million to the government for having overstated the cost of their installations to collect tax credits.

As thrilled as we are to see the attention and excitement being channeled into the solar industry, we advise solar shoppers to consider the risks involved with integrating a beta technology into their roof. Tesla is an amazing marketing machine, with an inspiring and voguish leader at its helm, but this may not the kind of investment to be the guinea-pig. There are many other options for aesthetic solar and the technology is only getting better. Please do your homework and consider all your options before making a decision. We’d be saddened to see bad press brought to the entire solar industry for a product that wasn’t ready for the residential market.