Will talk of Tesla's Solar Glass Tiles renew interest in Solar Shingles and building integrated photovoltaics
The announcement by Tesla Chairman Elon Musk in August 2016 that Tesla Energy would begin selling solar roof tiles this year (2017) has kicked off the debate again about the future of solar pv technology and the role of building integrated photovoltaics.
What is BIPV?
Building integrated photovoltaics is a name given when a solar panel that is also able to function as a normal building product such as a roof or a window. The idea is that rather than a roof and a solar panel attached to it the solar panel is the roof. Although we have seen quite a few solar carports where solar panels are used to provide shading and weather protection in car parks widespread usage of BIPV applications has not happened yet. As Elon Musk explained on his announcement, "It's a solar roof as opposed to a module on a roof." I think, this is really a fundamental part of achieving a differentiated product strategy – it's not a thing on a roof, it is the roof.
The vision is clear and beautiful, a world in which common building materials such as windows and roof coverings are made out of solar panels such that clean energy generation capacity grows in the process of normal building or renovation activity.
This could lead to a massive increase in solar capacity and lower the cost of solar and of energy generally. However, the gap is large between between current reality and this utopian vision. Both technical and financial factors have meant the neither solar shingles or any other BIPV application are anywhere near ready to be cost effective or scalable. As with the announcement of the Tesla Powerwall in mid 2015 the announcement that Tesla would be selling solar roof tiles was short on detail and long on vision. It is also worth noting that Tesla recently announced the canning of its much hyped DC Powerwall and the delay in the release of an AC version. There was no mention of how much, what wattage, or how they will in any way go close to competing with the cost of current mass produced solar panels (that can now be bought in container qualities from some manufacturers at 60 cents per watt) or how they will deal with any of the engineering challenges that need to be overcome to deliver a clean solution.
What solar shingles are out in the market now?
Two large manufacturers lead the field in this industry: Dow and CertainTeed. But new competitors include GAF and Corning, plus a slew of Chinese manufactures.
Disadvantages of solar shingles or solar roof tiles
They are expensive at up to five times the cost of current mass produced silicon solar panels.
They do not match other roofing material meaning although you have a slick looking section of solar panels it still contrasts to the rest of the roofing materials.
There is nowhere near enough history in the market to suggest that all of the engineering challenges inherent in these products have been dealt with.
Building-Integrated Photovoltaics (BIPV): what are they?
Even before the latest Musk upheaval, building integrated photovoltaic (BIPV) technology has been garnering attention as part of solar’s gradual expansion into broader markets like sustainable roofing design and green building.
Do we give Tesla another chance and believe in their roof tiles?
While throngs of media salivated over the 2015 announcement of the Powerwall its recent demise should remind us all that Tesla has a track record of making big announcements. A friend of mine Finn Peacock, an Australian ex-CSIRO electrical engineer and owner of this great website www.solarquotes.com.au wrote a very educated article about the DC Powerwall in 2015 that irked Tesla so much they threatened legal action against him for using information and an image from their own press kit. How dare he point out that they hadn't given any details of the electrical and engineering specifications and that this was unusual for a product that was only supposed to be six months away from release. The recent hype about the Tesla roof tiles seems a lot like this. Big on hype short on details and so for now I choose not to believe.
Having said that I do agree with Musk that a solar panel that actually is aesthetically more appealing than other roofing choices could change the whole solar game from a cost per watt game to a fashion trend.
At this point solar may end up installed in places where the economics alone would not justify it and this can't be a bad thing for the planet.
Tesla solar glass tile and roofing product materials
The asset most important to Musk's solar glass roof will be Panasonic's impressive panel efficiency and the durability of the tiles and shingles being made. Musk demonstrated in the launch the strength of his new roofing product, testing heavy weights on three common roofing shingles as well as his own. Sure enough, the Tesla roof was the only one that could withstand the weight and pressure. "It's made of quartz" explained Musk. "It has a quasi-infinite lifetime." This shingle and roof durability will be important to the success of this product. To succeed Tesla need to produce a product that is a better roof material than conventional roof materials and at least as good a solar panel as current conventional models. Solar panels currently have 25 year warranties, will the Tesla solar roof tiles be able to offer this level of guarantee?
The new roof will be offered in four model designs: Tuscan glass tile, slate glass tile, textured glass tile and smooth glass tile. This versatility and choice for homeowners will certainly change the consumer experience of "going solar." single most important innovation is this!
Going solar no longer involves accepting an aesthetic disadvantage
Cost will be an enormous challenge for this product.
At time of writing Tesla hasn't made any pricing information available. While some may say current solar panels are ugly (I don't share this view), they are also cheap.
Other engineering challenges also remain to be dealt with and I see the path for this product being best on all sides with difficulties.
However, it is an audacious play and I am one that hopes it works.