As more and more people become discouraged by their electric bills, they are considering going solar. Not only does it help with energy savings, but it is a source of clean energy that is good for the environment. Since the advent of Tesla’s solar roof many people are now wondering: solar roof or solar panels?
There are many important factors to consider when deciding whether or not to go with a solar roof or stick with traditional solar panels:
- Personal value
Solar Roof Vs. Solar Panels: What is the Difference?
Solar roofs and solar panels are fighting on the same side, so to speak, but they are using different tactics. Aesthetics play a big part in the difference, but that also results in a compromise of value for solar roofs.
You can think of solar panels as the more traditional method of solar energy. Solar panels became a mainstay in the space industry in the 1950s and have been slowly working their way onto homes since the 1970s. With the advent of the Solar Investment Tax Credit in 2006, the solar industry exploded.
By contrast, Tesla’s solar roof is fairly new. Mockups were unveiled in October 2016, just prior to Tesla’s buyout of SolarCity, and since then the solar roof has had three product versions, with the third being scalable and put into production. But it was not until 2018 that installation of version 2 began with version 3 beginning in late 2019.
It is unclear as to how many installations Tesla has made of the solar roof since version 3 rolled out of the Gigafactory in Buffalo. But the reviews of the roof, as well as its installation process have been mixed.
As noted in the introduction, the evaluation points for this article are:
- Personal value
A close look at the solar roof versus solar panels in terms of these four categories will reveal all the major considerations when making a decision between the two.
The question of which costs more, the solar roof or solar panels, is going to be on most consumers’ minds. Closely linked to that is going to be efficiency. The more efficient the unit, the greater the savings. Durability is also an important financial factor given the size and impact of the investment.
Finally consumers must consider the personal value of a solar roof versus solar panels. Ultimate value simply means which is best for you. There will be considerations under which you may want a solar roof and some under which you will likely choose solar panels. Understanding your own situation will help determine this value.
Solar Roof Vs. Solar Panels: Cost
Solar roofs and solar panels are after the same goal, converting sunlight into energy, but they are really two different products. Solar panels are grouped together and added onto your roof, covering the sections of it that are ideally suited to receiving sunlight.
Solar roofs, on the other hand, cover the entire roof. They are the roof. Photovoltaic sensors are placed into the glass tiles that make up the roof. But not all the roof collects solar energy. Some of the tiles are just tiles. How many tiles have photovoltaic sensors depends on how big the system is.
What throws off a direct price comparison is the fact that Tesla’s solar roof tiles are roughly $2 a foot while the inactive tiles are $7.65 a square foot. So in order to draw an accurate comparison for cost, you have to think about solar roofs and solar panels in a couple of different situations.
You will either be looking at going solar without needing to get a new roof in the next three or five years, or you will be looking at going solar and also needing to replace your roof in the next three or five years.
Cost Comparison if You Do Not Need to Replace Your Roof
This situation will probably represent most people who are considering going solar. Because roofs can last anywhere from 30 to 60 years depending on the material, there is plenty of time to add solar efficiency without replacing your roof.
In a straight comparison a solar roof is more expensive than solar panels. The reasons should be fairly plain. Solar panels are simply attached to the roof. The solar roof involves removing the old roof and installing a new one that receives solar. This means more:
To put it in concrete terms, a house in California with a 2,500 square foot roof and an average monthly electric bill of $250 would qualify, according to Tesla’s calculator, for a 10.2 kW solar roof system at $45,286 before ITC. Whereas the closest comparable solar panel system of 12.2 kW would be $24,600 before ITC.
Cost is the clear incentive in this situation. If your roof is fine, you can get a better solar system for significantly less by going with solar panels as opposed to the solar roof.
Cost Comparison if You Do Need to Replace Your Roof
In this situation, the cost comparison of a solar roof versus solar panels actually comes out somewhat comparable. Tesla’s marketing promise of having a solar roof that costs about as much as it would to replace your normal roof and put on solar panels, seems to be more or less true.
You will recall in the example from the previous section that for a home with a 2,500 square foot roof a 10.2 kW solar roof system would cost around $45,286. Now take our 12.2 kW solar panel system at $24,600 and add the cost of an asphalt roof at around $5 a square foot. The total becomes $37,100.
The overall price of each could change given the depending on the square footage and the size of the system you want to go with, so clearly these numbers are only by way of example. In some examples online, the cost is almost even depending on how it is calculated. But even in the example above the cost is at least in the same ballpark.
Solar Roof Vs. Solar Panels: Efficiency
Closely related to cost is the question of efficiency. The question of which system is the best at generating solar energy is going to have an impact on the cost of your system as it relates to the ultimate savings it will provide you in the years to come.
The solar roof, again, is at a disadvantage to solar panels. You probably noticed in the examples above that the solar roof costs more for a system that produces less. On average, solar roofs produce about 23% less solar energy than their solar panel counterparts.
The reason for this is the nature of the solar roof itself. The glass tiles that make up the roof can only support so many photovoltaic sensors in each one. Given the fact the roof is made up of a mixture of functioning and nonfunctioning tiles, the system can only be so large for any given house.
Solar Roof Vs. Solar Panels: Durability
The question that follows the others most closely is that of durability. It too is somewhat related to cost. You do not want to have to replace your roof or solar panels anytime soon. Furthermore, you do not want to have to pay for replacement or repair costs.
Fortunately for both products, Tesla offers great warranties. For solar panels they offer:
- 10 year complete warranty
- 25 year manufacturer warranty guaranteeing at least 80% of the panels’ power capacity
For the solar roof Tesla offers:
- 10 year warranty on the inverter
- 25 year warranty on the tiles, weatherization, and power
So if either Tesla product fails in any way, you can rely on a pretty good warranty from Tesla on their products. However, just because it will likely be covered, does not mean that you want to go through the hassle of repairs or replacement. So how durable are Tesla’s solar products?
Solar Panels Durability
One thing to note about the durability of solar panels is that the technology of panels has been around for more than twenty years, so while the panels themselves have changed in look and manufacturer, early generation panels have lasted for more than twenty years.
That is good news if you want to go with solar panels instead of a solar roof. The problem with new technology is always the track record, so at least solar panels have one.
Tesla Solar Panels in Question
Tesla solar panels are currently manufactured by Panasonic, which is another long lasting company with a reputation in the technology market behind them. Probably this is why Tesla has partnered with them for their product. But in the last couple of years, the durability of Tesla’s solar panels came into question.
Near the end of 2019, there were several incidents involving solar panels in Tesla installations. In a home in Massachusetts and another in Maryland there were fires, both relatively small, that caused damage to the homes and appeared to be caused by solar panels that Tesla owned.
In both cases maintenance that should have been carried out by the solar company was not accomplished because of poor communication with the customer. It did not help Tesla that around this same time, Walmart sued the solar company for negligence because of fires in several of its installations.
To be fair to Tesla, most of these problems seem to have been related to older panels installed when Tesla’s solar division was actually SolarCity (Tesla bought the solar giant in 2016). In the context of 400,000 SolarCity these incidents seem to be isolated. And, as noted above, Tesla installs a different panel system now.
Solar Roof Durability
One of the downsides to the solar roof is that there has not been a track record established to tell you about the durability of the roofs. This does not inspire confidence which is unfortunate because confidence is what the consumer usually wants when making a decision that is both expensive and enormous in scope.
That said, there are several indicators that you can look at to get an idea of what the durability of the solar roof is likely to be:
- Roof ratings including wind, hail, and fire
- The track record of the photovoltaic sensors in general and the Panasonic products in particular
Evaluating these categories can give you an idea of what the solar roof is rated to be capable of in terms of durability.
Durability of Solar Tiles as a Roof
When you are having a solar roof installed, it is important to note that the Tesla shingles are not just tiles that have solar cells in them. They have to function as a roof would function. For this the tiles have been rated by the third party organizations that rate all the roofing materials before they are used, and have received the highest ratings.
In the category of wind, the solar roof has a rating of Class F according to the ASTM D3161 standard, which means that the tiles can withstand winds of up to 110 miles per hour. This rating is achieved through independent tests of the tiles that create sustained “winds” (from high powered fans) against the tiles in a mock setup.
For the category of fire, the solar roof has been rated as a Class A material according to the UL 790 Standard. This means that the tiles resist fire in the most severe tests that they can stand up against in a test setting. This includes:
- Fire of intermittent flames and wind
- Sustained fire from a burning material (or “brand”)
- Fire from direct and sustained flames and wind
For the category of hail the solar roof has proven durable according to the ANSI FM 4473 Standard and received a Class 3 rating. This means that the tiles withstand simulated hail the size of 1 and ¾ inches directed at them at high velocities.
Durability of Solar Tiles as Solar Systems
For this you have to look at the warranty that Tesla provides, which was discussed above, and the track record, not of the tiles, but of the technological aspects of them, their guts, if you will.
Panasonic has provided Tesla with quality solar panels which include the photovoltaic sensors and the string inverters among other things. This has resulted in a solid product that Tesla has delivered to many homes in the form of solar panels. With the same “guts” at work in the solar tiles, this speaks to their durability.
However, you should note one thing. The roof tiles are warrantied according to their different functions. Specifically the warranties are broken down by:
- Tile Warranty
- Power Warranty
- Weatherization Warranty
- Inverter Warranty
One thing to note about these warranties is that they are all for 25 years except the last. The inverter warranty is for exactly half that time. It is hard to know why this is the case, but it is worth pointing out that the whole system is worthless without the inverter.
This means that the potential exists for you to have a solar roof that does not work and that you cannot afford to fix because the inverter has kicked the bucket even though everything else is just fine. There is not any documentation that this has actually happened, only that it is possible which makes it something to consider.
All this brings us to a comparison of the personal value of the two products. In the personal value of something, you are not only comparing the products, but what you want the products for. There is a difference.
The personal value of something can be figured like this. After you have gone through all the considerations detailed above (cost, efficiency, and durability, all of which are financially related), you add to it your considerations that do not necessarily have a financial component. These considerations generally fall into two categories:
- Bragging rights
Aesthetics is a pretty straight forward category. You care about how something looks, and how an appearance makes you feel is not something that you can necessarily quantify. Bragging rights is a little complicated, but no less a consideration.
Especially in the tech realm, some consumers like to own certain items because owning certain items gives them the ability to say that they own certain items. The solar industry itself had a strong element of bragging rights back in the day. If you had solar you could claim to have been on the cutting edge before almost everyone else was.
Aesthetic Value of the Solar Roof
For those who are saying right now that aesthetics do not matter, please consider the fact that one of the biggest motivators for the development of the solar roof was aesthetics. Elon Musk is the record (many times over) for expressing his displeasure over the appearance of solar panels.
So one of the biggest motivators for consumers who buy the solar roof is the fact that it is the roof and it looks sharp. The glass tiles can look pristine and hold their own functionally against normal roofing materials. For some people not having to have the typical solar panels on their roof is a big plus.
One negative to take note of in terms of the appearance of the solar roof is that when the tiles are dirty they look dirty. This may sound obvious, but take a moment to go outside and look at the roofs in your neighborhood. Do they look dirty?
Normal asphalt or tile roofs tend to be made of a material that already has an earthy appearance. Dust, dirt, and (if you live on the west coast) soot from fires tends to blend into the materials. Not so, the solar roof. The pristine black glass tiles show the dirt. But the good news is that a simple rain shower is enough to clean them.
Aesthetic Value of Solar Panels
Given the previous section, solar roofs would seem to have the edge in terms of aesthetics. Yes, they do, but with Tesla’s new solar panels the gap is shrinking. Tesla has carried its desire for aesthetics into the old products of the solar world, so now solar panels can even look sharp on your roof.
Consider the aesthetic problems of the old panels. They were:
- Bulky, rising above the roof at least 4 inches (not to exceed an astounding 18 inches in some localities)
- Ugly, being presented in utilitarian shades of grey and beige
- Industrial looking, meaning that the hardware for solar panels is clearly visible
While all of these problems are addressed in the solar roof, Tesla’s new solar panels take a worthy stab at it. They are black, streamlined with an aerodynamic feel, and have a low profile that hugs the roof. The new panels look like they are a part of the roof, not just sulking on top of it.
So if you decide to go with solar panels, you are not any longer settling for less of an aesthetic statement. Tesla solar panels may not have the edge over the solar roof, but they certainly have it over other solar panels.
Bragging Rights of the Solar Roof
Once again, bragging rights may seem a silly or even made-up category when making a purchase, but the reality is there are some people who want the status that goes along with owning something, and this can be particularly true in the tech world.
It is not necessarily a bad thing. If it weren’t for this market, many innovative products would not be around today. The solar roof may well end up becoming one of those products because bragging rights for solar roof owners are about as big as they can get and generally occupy two areas:
- Clean energy
In the realms of both technology and clean energy the solar roof represents a paradigm shift, which means that it is more than just an advancement on the order of putting solar panels on your roof. It is a fundamental change to an accepted way of doing things.
The accepted way of doing things is that a roof keeps the elements off your head. The solar roof means that the roof has more to do for your home than that. It runs your home by providing energy. Those who go with Tesla’s solar roof get to be at the forefront of this change.
Bragging Rights for Solar Panels
The problem with bragging rights is that you can lose them faster than you can say “AOL.” If the solar roof ends up being a non-starter then those who bought the solar roof have an emblem of shame sitting on their homes.
To talk about the bragging rights of solar panels is the same as saying that for most people who go with solar panels, bragging rights are not going to matter. It is enough to have a good product that runs well, has an established infrastructure, and lowers the energy bill.
As an added bonus you get to invest in clean energy and stick it to your local or state energy company (especially if you have a Powerwall or two). And on top of all that, if the solar roof bombs the bragging rights of the former default to the latter.
Solar Roof Vs. Solar Panels: Final Analysis
So here is a snapshot of Tesla’s solar roof in comparison with their solar panels.
|Solar Roof||Much more expensive if you do not need a new roof, comparable but still more expensive if you do||Less efficient than traditional solar panels||No track record, though it has the highest ratings as a roof|
|Solar Panels||Less expensive than the solar roof||More efficient at producing energy||Solar panels last longer than 20 years|
In terms of the personal value of solar roof versus solar panels, it simply depends on what you want. If you do not mind that a solar roof costs more and you are fine with their level of efficiency and the promise of the warranties covering the product, then you are probably the type of buyer who places a high value on aesthetics and bragging rights.
In that case, the solar roof is an easy win. The product looks great and it is at the forefront of what may well be a paradigm shift in the building and energy industries.
But if the cost, efficiency, and durability of solar panels is good enough for you, rest assured that, even if the solar roof takes off, solar panels are not likely to disappear any time soon.
Whether you go with Tesla’s solar roof or their solar panels, the important thing here is that you are going solar. Solar energy is one of the most viable sources of clean energy and worth investing in and expanding.
That said, it may not be the right time for a solar roof product. Companies prior to Tesla have tried to get a similar kind of product going and have failed. That does not mean that a similar fate awaits Tesla, but it may mean the market for this product is not quite ripe. If you are new to solar, there is no shame in going traditional.