First launched in 2016, Elon Musk’s Solar Roof system has taken the photovoltaic (PV) world by storm. Tesla’s Solar Roof is not the only solar roof tiles on the market but is some of the most attractive and most expensive.
Solar tiles offer a completely different approach to solar PV installations, the final product is, inarguably, far superior in aesthetic terms to traditional solar PV installations, and seeks to add a “cool” factor to generating your own power.
While Tesla claims its Solar Roof is competitive in terms of providing a two-for-one solution (you do get a new roof after all), ultimately, the proof of the pudding is in the eating.
So, is Tesla’s Solar Roof all it’s cracked up to be? Let’s take an honest look.
What is Tesla’s Solar Roof?
Tesla’s Solar Roof, like other solar roof tiles, is an innovative system of specially engineered roofing tiles or shingles. Unlike conventional solar PV panels that are mounted onto an existing roof, a solar roof acts as a direct replacement for existing roof coverings. The system allows potential customers to benefit from generating their own power without unduly affecting the aesthetics of their homes. Win-win.
Tesla’s Solar Roof consists of two main types of textured glass tile shingles. The first is purely decorative and is termed “inactive.” These look exactly the same as the second kind, called “Active”, to ensure a uniform look of the finished roof.
The “Active” shingles are effectively small, shingle-sized solar panels that are integrated into the main roof surface in strategic places to maximize their efficiency. In most cases, most of the south or west-facing areas of a roof will consist of “Active” shingles, with the rest of the surface consisting of the visually similar “Inactive” shingles.
“Active” shingles, like conventional solar panels, will also be fitted as close to the best angle of incidence to the Sun’s rays throughout the year. In the northern hemisphere, this is as close to a 60 degrees inclination as possible, which, on most domestic homes is around 30-45 degrees, depending on the pitch of your existing roof.
Of course, if you choose to install a Solar Roof, your old roof will need to be stripped and replaced in totality.
The system can also be used with a Tesla Solar Inverter to convert the direct current generated by the shingles to useable alternating current in your home. While non-Tesla inverters can also be used, the use of Tesla’s own proprietary equipment ensures the systems will run with fewer potential snags.
This inverter also enables you to tag on a Tesla Powerwall battery to store excess energy, if desired.
The system was developed in a collaboration between Tesla and its subsidiary SolarCity and was first announced in 2016. It wasn’t until 2018 that Tesla and SolarCity were in a position to begin the manufacture and delivery of their first Solar Roofs, however.
Since then, Tesla has continued to make improvements to the technology, with its latest variant, Solar Roof V3, boasting the best efficiency and durability to date. The product comes with a generous 25-year weatherization warranty.
Great, but what are some of the downsides? One is whether Tesla actually serves your geographical area.
For the most part, Tesla should be able to provide an installation in most of the continental United States. However, in some states, they may use authorized installers to do so.
The same is true for other parts of the world, with the rollout continuing around the world. If you are interested in finding out if they serve your area, the best thing to do is contact Tesla, or try to get a quote, and they will tell you.
How much does a Tesla solar roof cost?
According to data from actual Tesla quotes, their Solar Wall system costs approximately $1.80 per generated watt of electricity for their “Active” shingles. The cost of their “Inactive” shingles then varies depending on the complexity of the roof in question.
For “simple” roofs, i.e., basic pitched roofs start at around $13.30 per square foot. For more tricky roofs like hipped roofs or multiple-level roofs, these shingles should cost about $15.30 per square foot. For more complex roofs (i.e. cross-gabled, steep or variable pitched, multiple heights, or lots of obstacles), costs could be as high as $18.54 per square foot.
You will also be charged for the removal and disposal of your old roof at a rate of around $3.55 per square foot.
Just like any solar energy installation, the actual cost will vary depending on the size of roof coverage, location, and construction of the building. Smaller pitched roofs on a single-story home will be considerably cheaper than a large complex roof on a multi-story building, for example.
This is for a variety of reasons, but chief among them are additional costs for access equipment to higher roofs or increased time in labor to design and install the roof on larger and more complex roofs like cross-gabled roofs.
Tesla may also require customers to upgrade their electrical systems in order to actually work with their Solar Roof system. Upgrading elements like electrical panels can cost anywhere in the region of $5,000 and up.
However, to give you a rough estimate, using Tesla’s own calculator, a good-sized family home would cost around $70,000 dollars to install an 8.05 kW system before tax incentives. This quote is based on a home in Nashville, Texas, with a floor area of 2,500 feet2 (232 m2) and using an average monthly energy bill of $115 (this was the U.S. average in 2019, according to the EIA).
This, according to Tesla’s estimates, should be able to produce for this hypothetical home, somewhere in the order of 12,800 kWh/year, or roughly 100% of the building’s electrical energy consumption. You also get the added bonus (for additional cost) of energy storage with this system, which is a considerable advantage over some conventional domestic solar panel arrays.
If this estimate is accurate, that should provide a payback period (the time taken to recover your initial investment) of about 50 years, give or take. This will likely be closer to 40 years after tax incentives are factored in to reduce your initial capital outlay.
Another estimate for a 1,700 ft2 (158m2) roof in California with an electrical bill of $150 per month came in at $39,000 before incentives for a 6.13-kilowatt system. It should be noted that this quote was generated in 2022 and for a different state, so costs likely vary for that reason.
You should also remember that energy costs from the grid are likely to rise over time, so the “true” payback will likely be much shorter, ignoring any maintenance and cleaning costs of course.
We’ve chosen this square footage as it is about the average size of a new family home in the United States.
To put that into perspective, installing a similarly sized conventional solar panel array would cost around $26,000 before incentives. Using the same statistics as above would give you an equitable payback of between 15 and 22 years, depending on tax incentives.
However, remember that the estimated lifespan of conventional solar panels is also roughly 25 to 30 years, so you would probably need to replace the array after a few decades.
It should be noted, however, that such estimates should be taken with a pinch of salt. The final figures will likely vary widely depending on where your home is located if you were to actually order an installation.
You should also note that costs are likely to vary over time as labor, consumable, and material costs will fluctuate, given the current economic climate. There may be other costs, too, such as various local authority planning requirements, where relevant.
Solar panels vs. Tesla solar roof: which one is better?
Generally speaking, on a per watt average cost, Tesla’s Solar Roof is actually pretty reasonable, all things considered. According to some estimates, in the United States, Tesla’s come in at around $1.80 per watt. Traditional solar PV panels tend to cost around $3.00 per watt.
However, any direct comparison between the two is complicated by a few factors. The first is that Tesla’s Solar Roof is not just some PV solar panels but actually a new roof and some PV panels in one package.
Traditional solar PV panels are where your roof can handle it, simply mounted to an existing roof without needing to replace it. So, in order to provide a fair comparison, we’ll need to do a like-for-like summing up.
For the second example we gave above, a similar install would require the old roof to be removed and replaced with new roofing. This would cost around $935 for the tear-down and $11,900 for the new roof. If a 6.14 kW solar panel array was then also added at a cost of $3.00 per watt, the total cost for all works should be in the order of $18,420, give or take.
Based on this kind of comparison, the Tesla Solar Roof is clearly quite a bit more expensive – just under 40% more in fact.
However, remember a large part of this additional cost is Tesla’s relatively higher rates for roof tear-downs and disposal. Additionally, the replacement roof material is much more expensive than something like asphalt shingles.
While you could obviously get your old roof removed and replaced for much cheaper than Tesla offers, you also wouldn’t benefit from the complete Solar Roof package.
All is well and good, but the initial investment in the installation is only half the story. Both a traditional PV panel array and a Tesla Solar Roof will generate “free” power for years to come, saving you a pretty penny on your electrical bills.
After all, that was the entire point of doing the work in the first place, right?
So, how do they stack up on the payback front?
Well, a traditional 6.14 kW solar array in California would be expected to produce about 10,204-kilowatt-hours (kWh) of electricity per year. With current electrical rates of $0.19 per kWh, this traditional PV system should save around $2,000 per year and roughly $52,000 over the 25-year lifetime of the system (credit to SolarReviews for the figures). According to a report by Consumer Reports, however, a traditional 5.55 kW solar system will save about $64,000 over 25 years, with a payback period of around five years.
Tesla’s system, on the other hand, would generate savings of about $1,800 and a lifetime savings of $50,000. This includes a 30 percent Solar Investment Tax Credit but not state and local tax incentives, which could make the savings much greater.
This discrepancy is mainly the product of the fact that Tesla’s Solar Roof panel’s orientation to the Sun is determined and fixed by your existing roof pitch. A mounted PV system can be angled to maximize the amount of energy the system can generate, resulting in better electrical generation.
So, based on this, you could actually install a smaller traditional solar panel system, generate more power, and save quite a bit of upfront investment!
Although, again, this depends a lot on the situation. Consumer Reports also estimated that for a three-story, 2,700-square foot house in New York, Tesla’s system would save the homeowner almost $14,000 over 30 years; while installing the system on a 2-story, 4,500-square foot house in Texas would end up costing the homeowner £12,700 over the same period.
However, Tesla’s Solar Roof system is admittedly much more aesthetically pleasing than a bolted-on array of solar PV panels. But is that really worth the difference in cost?
This content was originally published here.