Tesla Solar Panels

I made the decision to purchase solar. With a pool pump and solar pool heating and A/C my electric bill has climbed substantially.

There is a world where I may plan to move in about 12 months so debated whether to move forward with solar. There are some studies that suggest owned solar will increase the value of a home. https://www.zillow.com/research/solar-panels-house-sell-more-23798/ I’d only need the value to increase by 1-2% to recoup the costs. I went for it.

My usage

Average Electric Usage per month over the last 12 months – 714 kWh with average total electric charges of $214 (includes delivery, generation, bonds, taxes and fees).

Total is 8568 kWh for the last 12 months (Important for later)

Bill PeriodTotal Electric UsageAvg. kWh/dayTotal Electric ChargesAvg. $/DayAverage Cost

Using the Tesla Solar calculator for my home address and an average electricity bill of $214 Tesla indicates I need 8.16 kW panels but that will only cover $184 of my bill.

This doesn’t compute with other solar quotes or Project Sunroof. Project Sunroof indicates for a $200 average electric bill a 4.8 kW system will cover 100% of my electric bill.

Using EnergySage solar companies are quoting 5 – 6 kW systems to cover my energy usage.

Using pvwatts default settings for my location suggests a 5.3 kW system will cover my annual electric needs.

However, since Tesla solar was price competitive I decided to proceed and figure it out late.

Sunday Nov 1st – Order online

I initiated the process and complete the process of taking photos of my roof, electrical panel etc. this included reviewing a design that showed the 24 panels (340W each). Sixteen panels on the south-facing roof slope and 4 panels each on west and east facing slopes. These are mounted below my solar pool heating. I’m unsure if it is wise to install electric solar below a water solar system.

Friday Nov 6th – Checking in

Texted to ask what next steps are. Rep indicated permits were submitted on November 2nd with an estimated timeline of 5-7 business days. I was given a number to call to schedule a home assessment, which I did although my earliest availability was November 19th.

Cumulative time: 5 days

Wednesday Nov 11th – Received update

Rep texted me to indicate permits were submitted. Meanwhile… I wanted to query the system sizing.

Texting with rep she indicated the 8.16 kW system for my house would generate an average of 1023 kWh per month. This is 43% more than what I actually need.

The only thing I can think is that their calculator is using a cost per kWh much lower than my actual costs. Do they consider baseline usage? Summer versus winter charges? TOU costs?

By my calculations I can cover 100% of my electric needs on average with 16.5 panels. Since I can get 16 panels on the south-facing portion of my roof that seems like a sensible approach.

Thursday Nov 19th 2020 – Home Assessment

Spoke to the assessor and queried the system sizing and the location of the panels. I indicated I’d prefer to simply have 16 panels on the south-facing portion of my roof and forgo the other 8 panels on the east and west portions. He agreed to record this on his assessment.

I know my electrical panel will need upgrading. It is original to the 1979 portion of the house, is 100 amp and totally full. I asked about that and he said engineers would review.

I won’t count the time it took me to schedule the assessment as elapsed time.

Saturday Nov 21 – Check in

The status had not changed on my account, so I queried my customer support rep to ask for next steps. She indicated waiting on permitting (although I thought that was done?). Did not indicate anything about the electrical panel.

I also mentioned my HOA Architectural Review Board. As part of the intiail process they asked for the name of the HOA but did not ask for any contact details.

Cumulative time: 7 days

Tuesday Nov 24 – Received blueprints

Received blueprints for system. Updates for the 16 panels on the south-facing portion of roof only for a 5.44 kW array. I’m asked to submit to my HOA architectural review board and email Tesla when permit is received, however I’m not expecting this to block installation date.

I texted again to ask about electrical panel and any upgrades and costs associated with that.

The design indicates Tesla’s estimate for system production: 8832 kWh. This is in excess of my actual last 12 months electricity consumption. I’m comfortable, then with my decision to downsize to 16 panels. It begs the question what Tesla are doing on their website estimator to suggest that a much larger system would only cover a small portion of my bill.

Wednesday Nov 25 – Received new document notification

I received a document indicating the roof was not suitable as-is for installation. I don’t get a specific reason but a list of possible reasons. It includes a $5,280 pre-construction cost to re-roof the portion on which the solar panels will be installed.

I queried whether there were going to be any other pre-construction costs, such as electrical work. The rep indicated she would get back to me.

Cumulative time: 11 days

Monday November 30th – Received multiple notifications to review documents

Receiving reminders to review and sign the layout and pre-construction documents. I queried the rep again to ask if there would be any more pre-construction costs, I do not want to sign up for work without knowing the full costs.

The next day the rep indicated there was no other pre-construction work. I signaled my surprise since I’d been told previously I would need an electrical panel upgrade to install solar and since then I’d had A/C installed which required some hoop jumping and re-purposing of a disused electrical dryer circuit.

The next day (December 2nd) the rep said she would review with Project Management team.

I’m going to count this time since I have open questions I am waiting for response for.

Cumulative time: 16 days

Monday December 7th – Queried rep again

I’d received multiple notifications to review my documents but since I was expecting a response on the electrical panel I took no action. So I queried the rep again to find out when I’d get an answer.

Same day she replied and indicated that they can move forward with my current electrical panel.

Cumulative time: 23 days

Saturday December 12th – Decided to proceed

I decided to move forward. While the partial re-roof was an unfortunate additional expense, with the smaller system, the total costs were still in-line with what I had originally budgeted.

I signed the documents.

Soon afterward the website updated to indicate:

Installation: Coming Soon

We’ll reach out to you when your installation is ready for scheduling.

I won’t count the time it took me to make a decision.

Cumulative time: 23 days

Monday December 21st – Queried when installation would be scheduled

Since I hadn’t heard anything I queried the rep to ask when I could expect to be contacted or how far out installation was running. She told me she could not tell me anything about installation and I would be contacted “once approval is received to move forward”.

Cumulative time: 32 days

Tuesday December 29th – Queried again

I asked again when I’d get an update on approval to move forward and contact from scheduling team. The rep said she would look into it.

Cumulative time: 40 days


So far almost 2 months in and 40 days of time spent on the Tesla side.

It really only took 11 days (not counting time to schedule Home Assessment) to get to documents.

However it took 12 days to get to a final answer on the electrical panel.

It has now taken 17 days since I signed and no installation scheduled (Christmas period in there, but I imagine only a couple of days off?)

Tuesday December 29th – Roofing Update

Coincidentally I received an email from a project coordinator on the roofing team, copying in a roofing contractor in my area indicating

  • you can be expecting word from our scheduling department to help coordinate your construction schedule within the next 5 business days.
  • You will also be contacted by a representative of ACCI Roofing, to discuss the specifics of your re-roof

Thursday January 7th – Queried

I waited a full 9 days (it was over New Years) but did not receiving any contact from the scheduling department. I sent an email.

I did receive a reply same day indicating someone from the roofing contractor will contact me to schedule and the installation would be scheduled following that.

Cumulative Time: 49 days

Wednesday January 13th – Roofing Contract

Finally 15 days after receiving the Tesla email I received an email from the roofing contractor with a contract to sign indicating that their schedule is 4-6 weeks out. I had a question about the tile selection since this is a partial re-roof.

Cumulative Time: 55 days

Thursday January 14th – Queried

Responded to roofing contractor email with questions about tile selection / color matching.

Wednesday January 20th – Roofing Scheduled

Emailed follow-up to roofing contractor. They called back and explained that they don’t actually replace the tile, rather prepare the roof, flashing, put down shingles and then once solar is installed place the original tile around the solar installation.

Contractor indicate they had a short-term availability and could come next day which I accepted.

It basically took 22 days from the Tesla email to scheduling the re-roof. If they didn’t have the short-term opening, I might have been waiting another 4-6 weeks.

Thursday January 21st – Roofing Project

Roofing contractor came and did the partial-re-roof.

Following that I emailed Tesla roofing project manager to query when they’d schedule installation.

Friday January 22nd – Install Scheduled

Received a call from Tesla scheduling indicating they had an opening tomorrow. Since the weather was showing an 80% chance of rain I asked what would happen if it rained. The person indicated they’d still come out and attempt to install as much as possible or would reschedule hopefully within the next couple of weeks. Seems like a bit of a risk to try to bring the installation in by 4 days for it potentially to be delayed by a couple of weeks. Decided to take the risk and accepted that opening.

Later in the day I received a text from my usual rep indicating due to potential for rain, they’d reverted to my original installation date of Wednesday 27th…

And then on the 25th they called me to say they could do it on the 26th…

Cumulative Time: 54 days

Tuesday January 26th – Install

Tesla team installed the panels and system. They were here for about 6 hours. I later received an email that inspection was scheduled for tomorrow.

Wednesday January 27th – Inspection

System was inspected and passed. I received a note that final payment for the system was due. I paid from my bank account.

Instruction was that I should receive contact from my electricity provider (SDG&E) within 10-12 days for approval to turn on. Reading SDG&E website indicates that it could take 5 business days for permission to operate. They mention a fast-track process but I don’t know if that was followed or how “fast” fast-track is.

I also emailed roofing contractor to ask for next steps for finishing the roof.

Cumulative Time: 59 days; Calendar elapsed Time: 88 days

Friday January 29th – Receive PTO

Received an email with Permissions To Operate from Sempra Engergy (owner of SDG&E).

I went outside to flip it on. Panel breaker was already on, the disconnect was already on, turned on the inverter.

The website “how to” indicates it could take up to an hour to see data in the app. However, am concerned that the gateway box is too far from my inverter to work.

Data was not showing up. I texted my Tesla rep to find out if I needed to do anything but all I received were instructions to turn the system on. I rebooted my gateway box. A few hours later once the website changed to indicate it was time for me to download the app, the data began to show up. So I do think Tesla had to enable something on their side.

Cumulative Time: 61 days; Calendar elapsed Time: 90 days