Published on January 26th, 2020 | by Kyle Field0
What You Should Know Before Signing Up For A Tesla Solar Roof
January 26th, 2020 by Kyle Field
The Tesla Solar Roof finally makes solar beautiful and easy to look at for folks who don’t appreciate the look of conventional solar panels. I for one love solar and have always enjoyed the look of solar panels on a roof, but I also think the Solar roof tiles are more beautiful, more functional, and more durable than most traditional roofing surfaces.
We unfortunately lost our home in the 2017 Thomas Fire that blazed across Southern California, but were fortunate enough to be selected as part of Tesla’s pilot program for installing the Solar Roof on a new home after putting down a $1,000 deposit on Tesla’s Solar Roof webpage.
Installing a Solar Roof on a new home is similar to the process for installing a roof with a bit of solar tech blended in for good measure. With this being one of the first new homes built with a Solar Roof (if not the first), I’m unpacking the process of the installation here for everyone to learn from it. It’s worth noting that our roof is a Solar version 2/2.5, so the process for installing the current version of the Solar Roof version 3 will be a bit different.
Purchasing a Tesla Solar Roof is very similar to the process of installing traditional solar on the roof. It starts with an initial phone consultation. As a new build, Tesla looked at our approved plans to map out the complexity of the roof, where it made sense to install photovoltaic tiles versus glass tiles, and the like. This is a unique variable that does not exist in the traditional solar or traditional roofing industry. We first engaged with Tesla via a phone call to talk through our project, the installation, size, requirements, etc., to give Tesla an idea of where we were in the process, as well as a chance for us to ask questions of Tesla directly.
The look and feel of a Tesla Solar Roof is the same regardless of whether the individual tiles themselves contain the photovoltaic cells or not. The number of tiles containing photovoltaic cells in a Tesla Solar Roof can be fine tuned to meet the needs of the customer, up to the maximum capacity of the roof based on its size, shape, pitch, etc. For our roof, we opted to install the maximum number of photovoltaic tiles, which translated to 10.59 kW.
We did this because our new home is fully electric, with no fracked gas even piped to our house from the curb. Why pay for it if we are never going to use it? The Powerwalls and solar provide a resilient, durable, sustainable source of energy regardless of what happens on the grid in the event of a grid failure. We also have two electric vehicles, so the ability to generate all of our own power for our home and both vehicles was one of the foundational objectives of the rebuild.
Tesla put together a useful sales kit that rolled all of the key facts into a single PDF document. For our home, Tesla was able to squeeze a 10.5925 kW Solar Roof into the 1,881 square feet / 175 square meters of roof surface. They estimated it would produce 13,126 kWh year. It’s worth noting here that we could have achieved a higher total kilowatt-hour output with traditional panels, but the aesthetics of the Tesla Solar Roof outweighed the benefit of the additional production.
The Tesla Powerwall can be hardwired as either a whole home backup if there is enough capacity, or to backup only essential loads. In this configuration, homeowners are able to select a few circuits that will be powered by the Powerwalls when grid power goes down. With our home being fully electric, with lots of high-power appliances, three x 50 amp EV chargers, and a future run for a hot tub in addition to our other base loads, our home simply had too many things to back up for us to cover it all with two Powerwalls.
We split out the highest-draw items from the list of circuit breakers in our panel — Tesla worked with our electrician (remember, it’s new construction) to map out the split of which circuit would go where. We were able to back up the majority of our home with the Powerwalls, including a single 40 amp EV charger for us to run off of a Powerwall just in case. It’s better to have the option than not, but it is not likely that we will be charging a 75 kWh Tesla Model 3 off of just 27 kWh of Powerwall storage capacity if the grid is down.
All of the finances are also included in the quote, with a comparison of how the Tesla Solar roof stacks up against a traditional roof + solar panel installation. With version 2, our Solar Roof install was a bit more expensive than the new version 3, but it still wasn’t a bad financial decision. Imagine how much better the financials are going to look when we starting seeing some actual pricing rolling out for version 3.
After signing the contract, Tesla requested a $2,500 payment to cover a site visit. For us, building from a dirt lot on up, this was comprised of reviewing the plans and building out an actual system layout for our house on blueprints. Solar systems here in California must be permitted and having a good set of plans is foundational to that.
For some homes, Tesla will come out with human inspectors, and for others, they will send humans equipped with drones to give them a better idea of what’s up on the roof. It is a great way to leverage technology to get better information than humans on the roof can, and in a safer way.
Let The Install Begin!
In parallel to the site visit, Tesla started ordering materials for the installation and worked with us to schedule the installation date. We connected their project lead with our general contractor, who coordinated the specific timing of the different phases of the installation. As with most construction, the schedule is a bit fluid, so communication was key and they worked together to keep the timing as tight as possible.
As soon as the first Tesla materials arrived on site for the installation, they sent over an invoice for half of the remaining balance. We paid with a credit card because that’s a lot of points. Most contractors require payment via check to avoid the fees, so it was a welcome surprise. Though, it is something I would expect will change as they tighten up the financials.
For standard rip-and-replace roof installs, Tesla estimates their work to take 2 weeks for a version 2 roof install. That should be down to less than 1 week with the Tesla Solar Roof version 3 with no glass cutting required, larger panels, and streamlined wiring. The bulk of our installation happened up on the roof of the second story. That took nearly a full two weeks by itself, with only 2 or 3 additional days of work needed down below to install a few more sections of roofing and the Powerwalls as well as to button everything else together in the garage.
Powerwalls & System Check
These later stages of work happened toward the end of our home rebuild, with the trim pieces of roof over the garage going in after the stucco was up on the rest of the house. The Powerwalls were installed after the electrical was roughed in, giving Tesla enough to work with as they added their Gateway (version 1 for our house, though the much better looking Gateway version 2 is already starting to trickle out to some lucky customers), the auto transfer switch, another subpanel for solar, the Powerwalls, and a large fused disconnect.
At that point, Tesla’s team tested out the functionality of the system, connected it up to the internet over the integrated cell connection, then proceeded to turn it off. During their commissioning of the system, it was active on the network and even showed up on my Tesla app for all of five minutes. As we did not yet have a meter from our utility installed on the house at the time, Tesla had to shut the system off until the meter was installed.
I personally think it would have been awesome if Tesla could have enabled the system at that point and simply let us run off of our rooftop solar plus storage system until grid power was ready, but that’s just not their process (yet?).
A few weeks later, they came back out for the final inspection to get the permit from the city. In advance of the permit meeting, Tesla’s technician double checked the power flowing through each of the rapid shutdown devices (RSDs) just to confirm everything was still humming along nicely. It was. I was surprised at how manual the process was and expect Tesla to add intelligence to these RSDs in the future to further streamline the installation. If technology can speed the process or make it more cost effective, or both, then apply technology. It’s the Tesla way.
They looked over the plans and confirmed the system was installed per the plans and greenlighted the system.
Permission To Operate
From there, the system is effectively punted over the wall to the local utility. Here in Southern California, where rooftop solar systems are a dime a dozen, they take interminably long. The local utility, Southern California Edison, takes an estimated 6 to 8 weeks to review things on their end and give a green light to the system. During this time, the system is fully built, ready, permitted, etc., but it needs the stamp of approval from the local utility before it can officially push power back to the grid as part of the local net metering scheme.
If this were a system purchased a few days ago and rapidly tossed up on the roof, I could understand the time frame, but for a system they knew was coming for nearly a year, an additional delay of nearly 2 months is inexcusable.
Learnings is a word I gleaned from my nearly two decades working at Procter & Gamble. In my corporatized brain, it speaks of lesson learned, of thinking back on what could have been done better, and of what worked well. It’s a positive word that embodies the notion of continuous improvement.
Tesla’s Solar Roof is a beautiful product that makes residential rooftop solar palatable and financially attractive to mainstream consumers and builders around the world. For our install, the cost was okay for us, but it has significantly improved with version 3.
The Solar Roof is a good looking roof! After watching it be carefully assembled, the blue-black tones of the roof look really sharp. Being glass, it also has an occasionally reflective personality that I simply love. The only thing I’m bummed about when it comes to aesthetics is that because our house is so tall and awkwardly placed in our neighborhood, we don’t get to see the roof as much as we’d like, and that speaks volumes about how nice it looks. I don’t remember saying that about our old comp shingle roof…
The Solar Roof is sure to be a fantastic new market segment for solar, but we need more solar panel builders to move towards building-integrated photovoltaics. Tesla can’t do it alone, but if the company’s automotive story is any indicator, we can be sure that Tesla staff will work their tails off to consume the entire market if nobody else will.
Version 2 of the Solar Roof was clearly not optimized for high volumes, as made clear by the extreme complexity of the mounts that underpin the complex network of tiles, the manual wiring between each tile in a brick, and the need to cut the glass tiles on site to match up the Solar Roof to all the various angles of the roof. Cutting glass is painstaking and tricky, and inevitably induces invisible cracks that I’m sure will manifest over time.
This issue has been addressed by Tesla already with Version 3 of the Solar Roof, which fills me with hope for the future of residential rooftop solar. Aesthetics aren’t everything, but they are important for many people, so why not address that segment of the market with a great product. The Solar Roof does this in spades.
Optimizing the new roof for scale gave Tesla the ability to produce even more Solar Roofs at a lower cost that’s attractive to many more homeowners. The amazing thing is Tesla was able to not only optimize the cost of the system, but also improved the time to install a system with the new design. That means less disruption to homeowners and less money that goes into putting a system on the roof.
Glass is awkward to walk on. A firefighting video we talked about months ago addressed this specifically for firefighters, but the same holds true for homeowners, contractors, and the like. I don’t go on my roof very often, but when I do, it would be nice to feel safe up there. As it stands, walking on the tiles feels much like you would imagine — the layers of glass creak and moan under the strain. They are also super slippery when wet, so I don’t recommend walking on them if your shoes are wet. I’m hoping this has been improved in version 3 of the Solar Roof, but if not, perhaps Tesla can work on it for future products.
To run the numbers on a Tesla Solar Roof, Solar, or Powerwall for yourself in about two minutes, use my referral code (https://ts.la/kyle623) and you can save $100. Tesla is just one of many solar providers out there, so don’t go with Tesla just because I did. Remember, I compared offerings from Sunrun, Sun Power, sonnen, and Tesla before making what I felt was the best decision for my family and recommend you do the same.
Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.