By Diana McKeown & Jessi Wyatt
Just as the Midwest has seen increases in on-site solar rooftop development, there’s been talk for several years about emerging solar technology as people become increasingly familiar with seeing roof-mount solar photovoltaic (PV). New on the horizon, through energy innovations from household names like Tesla and MIT, are things like Solar Skins and solar shingles, which are being included in conversations about the future of solar.
However, very few communities in the Midwest are thinking about solar shingles. Solar-readiness programs for communities, like SolSmart and Solar Possible–which help communities prepare for solar through best practices in zoning and permitting or help mitigate the soft costs associated with rooftop solar–still focus almost exclusively on ground mount and mounted roof systems. As we think proactively about the future of solar, we start to ask: what are these solar shingles all about and where might they make sense in an increasingly renewable landscape?
To get some local insights, we reached out to one of the few companies in Minnesota that is actively working on solar shingle installations, Litty Solar, to answer some questions on solar shingle technology and logistics.
What’s up with solar shingles?
Like conventional roof-mount solar photovoltaic systems, solar shingles also use the sun as a power source to generate electricity. Like a solar panel, each solar shingle is comprised of photovoltaic (PV) cells. This type of solar system is typically referred to as a building-integrated component, unlike a roof-mount solar system (whether on racks or not). Solar shingles are also referred to as solar tiles. The lifespan of the system is the same as a roof-mount solar PV, or around 25 years.
Are they in use elsewhere?
Solar shingles are in use in many parts of the country and around the world. Major players in the energy technology sector are experimenting and designing different types of building-integrated solar technologies. However, just as roof-mount and ground-mount solar PV are more prevalent in the Southern United States, and in states with more progressive solar legislation, like California, so too are alternative solar technologies, like solar shingles, more common. In addition to known brands like Tesla, there are two major solar shingle manufacturers in the market: CertainTeed, who make the Apollo II, and RGS who makes the Powerhouse 3.0.
When do they make sense?
Solar shingle technology appears very similar to a traditional roof shingle, making it sometimes difficult to distinguish a roof covered in solar shingles from a non-solar roof. This serves as a design or aesthetic benefit; especially in places where homeowners associations (HOAs) or other city zoning prevent larger roof-mounted systems, solar shingles may be the sleeker, amenable option to get solar energy generation. A similar size to regular shingles, solar shingles are often the same weight or only slightly heavier than typical tiles. This means that for building rooftops where structural weight-bearing is a concern for larger roof-mount systems, solar shingles may be a viable alternative.
There’s also a financial consideration. For many considering any solar installation, the federal solar tax credit or investment tax credit (ITC) allows all residential and commercial installations to deduct a portion of the cost of the system from federal taxes (30% in 2019, 26% in 2020). However, what qualifies as a solar installation under the federal tax credit varies by type of system installation. For regular roof-mount PV, the tax credit only applies to the system itself (not installation). For solar shingle installations, the cost of labor can be included. For some situations, this could result in economics favorable to a solar shingle installation versus a traditional system.
What else do you need to know about solar shingles?
The upfront cost of solar shingles is typically higher than roof-mount solar PV panels. The market for solar shingles, unlike more common roof-mount systems, is nascent in the Midwest. This means that there are few installers to choose from, and communities may be less familiar working with residents or businesses on any permits for the installation. Finally, weather is a consideration. Solar PV does run more efficiently in the cold. However, despite a handful of private residential installations across the metro, there is minimal public data on how solar shingle technologies operate during Minnesota winters. There is also some concern about reduced efficiency in the summer months, as the solar shingles lack air flow underneath (unlike a racked roof-mount system) which can help the module stay cool.
So, what do the economics look like for a typical homeowner?
Understanding that the cost of any solar system–roof-mount or shingles–will vary dramatically based on a suite of factors like size of roof, aspect, color, slope, material, etc., we asked Litty Solar to break down the financials and explain what a solar installation looks like for a regular PV system versus solar shingles.
| Item | Regular PV System | Life Span | Solar Shingles | Life Span |
| Asphalt Roof / Upgrade or Replacement | $20,000 | 30 years | $20,000 | 30 years |
| System (5-10 kW) + Install | $30,000-$40,000 | 25 years | $35,000-$45,000 | 25 years |
| ITC Fed Tax Credit | 30% (drops to 26% in 2020) of system ONLY = $9,000-$12,000 | One-time tax credit | 30% (drops to 26% in 2020) of system + roof (including labor) = $16,500-$19,500 | One-time& tax credit |
| Total Cost (System + Roof - ITC) | $41,000-$58,000 | $38,500-$45,500 |
The roof upgrade or replacement stays the same–although thinking about timing a solar install with a roof upgrade may make sense. The system costs for the solar shingles are more expense than a regular PV system. However, the ITC tax credit is where the solar shingles could make up some of that cost. The final range shows significant overlap, identifying that solar shingles may not be as cost prohibitive as their initial cost would appear.
Pros
- Aesthetics - amenable with HOAs
- Lightweight – demanding less infrastructure installed on the roof
- For some, financing is better than roof-mount (because you can get the tax credit on labor + tech, versus just tech)
Cons
- Cost for tech alone is higher than traditional solar PV roof-mount
- Nascent market; there are currently a limited number of installers in Minnesota
So what?
Thinking about the future of solar, there may be increasing applications where existing barriers to on-site solar–like homeowners associations, building or roof restrictions–can easily be mitigated by alternative solar technologies like solar shingles.
