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Solar Power Monitoring and Billing through SolarCity
After experiencing some growing pains with my SolarCity installation, I’m happy to say that I’ve been up and running since February 23rd of 2015 and ready to share my experiences with how the system is monitored and billed.
Savings
The savings on your electricity bill begin immediately after installation of your SolarCity system, and affects both the supply and delivery portions of your bill.
Savings can be pretty dramatic depending on the size of the system and, obviously, how much sunshine your region experiences. The following utility bill is a great example of how I was able to reduce my energy dependence from the grid by over 90%.
However, despite the reduction in energy needs from my utility company, the cost is not directly proportional to the amount of energy used. Here’s why.
Billing
Having such a drastic reduction in kWh needed from the grid actually comes with a price. Almost everyone who signs up with SolarCity opts-in to a Power Purchase Agreement (PPA) which means you pay nothing upfront (for the gear, install etc.), but you pay SolarCity for every kWh their system generates. That rate can be variable or fixed. I pay a fixed rate of $0.1420 per kWh generated for 20 years. That may sound high to you but considering my local electricity rate is $0.2470, I’m saving 43% per kWh.
It takes SolarCity some time to get up and running with their billing system. For me it took them 3 months to send me the first bill and because of that I received a hefty bill (thankfully late winter months) for all 3 months in one shot. After that, the bills arrive monthly (note that SolarCity requires EFT/Autopay to be set up).
The bills are simple and only state the amount of kWh generated, the rate you pay, and the total amount owed.
SolarCity collects data generated through their system via a standard internet connection, which they also use for billing purposes. On the first (large/3 month) bill I received, I noticed a difference of 10% (additional cost for me) between the billed amount and the amount the system had reported being generated so I naturally brought this to their attention. The customer service folks that I spoke with weren’t of much help and just told me to read each the meters at the beginning and end of each month if I truly want an accurate reading of how things get billed. So, that’s what I did.
Since inception I’ve saved $320 (over roughly 3 months) or about 42% off what I would have paid National Grid. And the system cost me nothing to install (I actually got a $1,000 Tesla-owner check from them).
They also have an estimated cost savings on the front page when you log in but it’s totally incorrect:
The mistake they made here is that they’re assuming your electricity rate doesn’t change over time. My electricity rate rose significantly after I signed up for SolarCity and because of that I’m getting a larger savings than what they’re reporting.
Monitoring
Monitoring happens online through MySolarCity.com. The interface is geared more towards new referrals than for actual owners of their system. The section I use most often is the Power Guide.
Power Guide gives an hour by hour break out of your energy generation along with the weather pattern for that day (ie. how much daylight, cloud coverage …). Hovering over each colored bar will show you the energy generated per inverter. The data can be downloaded in a CSV format and then imported into Numbers or Excel for your own post processing.
If you have multiple inverters, the CSV data for the day is a bit of a pain to analyze since it also includes the energy generated every 15 minutes per inverter.
Power Guide also includes a summary for the year.
The platform also provides a view of your energy generation as it happens in real-time which updates continuously.
Having this features allows you to watch the sun rise and set as viewed through the perspective of your panels which is kind of fun.
It’s not totally accurate as I’ll see data from certain days which look completely off.
API – Not
I’ve set up automated tweets for detection of Tesla Superchargers in real-time and decided to the same by sharing my SolarCity data through my home-grown program that fetches the data from Power Guide and then tweeting it.
It would be really nice if SolarCity decided to create a simple REST API that would allow owners to fetch their data.
Summary
SolarCity makes a lot of sense when it comes to cost savings and they’re able to provide this with no upfront cost to the owner. One needs to analyze the effective savings based on the cost incurred when generating energy through the SolarCity system versus your electricity cost, and then decide if the savings is worth the hassle. I’d recommend filling out their contact form and sign up for a consultation to get started.
The billing and monitoring side of SolarCity could definitely use some improvement, and hopefully this will improve over time as the business continues to grow.
I hope this post and series has been helpful. Let me know if you have any questions or thoughts in the comments below.
Elon Musk
Tesla’s secretive “Project Crystal Sun” gets a big green light in Texas
Fort Bend County approved four incentive agreements Thursday for Tesla’s proposed $10.1 billion solar factory.
Fort Bend County commissioners on Thursday approved a package of tax incentives for Tesla’s proposed $10.1 billion solar cell factory near Needville, Texas, giving the company one of the last local approvals it needs before it decides where to build. All four Tesla agreements passed 4 to 0.
The votes covered a property tax abatement inside Reinvestment Zone No. 34, a Chapter 381 economic development agreement, a foreign trade zone non-objection paired with payments in lieu of certain taxes, and a separate payment in lieu of taxes “true up” agreement, according to agenda notes from the Fort Bend Commissioners Court meeting.
The project, known internally as “Project Crystal Sun,” would make solar cells and finished modules on roughly 3,000 acres near FM 762 and FM 1994, south of the Brazos River. As Teslarati reported when the filing first surfaced in August, Tesla’s application under the state’s JETI Act splits the investment into $1.5 billion in real property and $8.6 billion in equipment, with 9,712 permanent jobs projected by 2033 and commercial operations targeted for the first quarter of 2029. The plant would handle the full chain from ingot and wafer production through cell testing.
Inside Tesla’s secretive $10 Billion “Project Crystal Sun” filing
Thursday’s approval does not lock in the site. Tesla has told the Texas Comptroller it is still weighing other locations, and site selection adviser David Dennison told Lamar Consolidated ISD trustees in September that the race had narrowed to Fort Bend and one out of state rival with a “very compelling package,” according to the Houston Chronicle. Tesla hopes to decide before the end of 2026, and the incentives still need sign off from the Comptroller and the Governor’s office.
Local officials have now done nearly everything within their control. Commissioners created the reinvestment zone in an August 24 special meeting, with Interim County Judge Daniel Wong formally withdrawing himself over his engineering firm’s past work with Tesla. Lamar CISD trustees voted 7 to 0 on September 15 to advance a JETI agreement that would tax Tesla’s qualifying property at 50 percent of its value for maintenance and operations from 2029 through 2038.
The plant lines up with a target Elon Musk set on Tesla’s Q4 2025 earnings call in January, when he said the company would “work toward getting 100 GW a year of solar cell production, integrating across the entire supply chain from raw materials all the way to finished solar panels.” In March, Tesla was reported to be negotiating a $2.9 billion purchase of Chinese solar manufacturing equipment bound for Texas. The Houston area already hosts Tesla’s Megafactory in Brookshire, where Megapack 3 production has started. Tesla said on its Q3 call that Megapack supply for 2027 is nearly sold out, and Musk wrote on X Thursday that the company is “increasing production of Megapacks as much as possible,” as demand from data centers climbs.
Tesla revealed plans to develop its own maps internally to fix Navigation issues and give owners more control over their routing.
On the company’s Q3 2026 Earnings Call, a question was asked about FSD Navigation issues, particularly speed limit recognition, parking, and routing. These are issues that surface from version to version and seem to be seriously challenging for Tesla’s AI team to resolve.
Tesla’s Head of AI, Ashok Elluswamy, said in response to the question:
“You’re totally right that we shouldn’t be depending on external people’s maps. So we are building our own maps, but not like the same way as OneMoreMap. We are building an entirely new architecture with essentially AI-based mapping and navigation.”
He continued:
“It’s going to be super awesome. It’s going to be integrated with voice. You can talk to it, ask for different routes. It’s going to learn your personalized preferences, plus the fleet preferences. The collective intelligence of all the cars is going to flow into making the maps and navigation super cool.”
Elluswamy said this issue should be confronted, and the mapping should be available for people by the time the v15 release starts deploying to customers.
“And over the next several months,” he added, “it’s just going to take over all of the navigation functions, parking, destination handling. And it will know you better than you know yourself in some regard for the driving task, and then handle it fully.”
Tesla Summon got insanely good in FSD v14.3.2 — Navigation? Not so much
Navigation is perhaps the most notable complaint with FSD, and although it has gotten better, it is still flawed. Much of the time, FSD will take people on routes that are not preferred by the driver, but Tesla tried to combat this with a routing feature in the Summer 2026 Update.
Tesla currently relies on Google for map data, but it is sort of counterintuitive to believe the company would rely on a third party for this. These improvements will be welcome, as routing and navigation have been such a pain point for so many owners for so long.
Quotes via Motley Fool
Tesla Full Self-Driving (Supervised) showed a record attach rate at delivery for new vehicles in the third quarter of 2026.
75 percent of new vehicle deliveries in North America included a subscription to FSD software, up from 55 percent in the prior quarter, a 20-percentage-point sequential gain in the company’s most mature market.
Tesla Q3 2026 Earnings results: in-line revenues, slight beat on EPS
Tesla shed light on the Q3 Shareholder Deck that 75 percent of new deliveries came with an FSD subscription:
“FSD (Supervised)⁴ attach rate continued to grow, reaching over 75% of new vehicle deliveries in North America – our most mature market – a nearly twenty percentage point sequential increase. We believe that FSD is driving demand in markets where it is available, and we continue to work with regulators to get it approved in other markets. “
The higher attach rate accompanied strong growth in the overall FSD consumer base, as active subscriptions rose to 1.75 million, a 67 percent year-over-year increase. For the first time, more than half of paid customers are on the monthly subscription, which is priced at $99 per month in the U.S.
People are buying FSD with a car attached, not the other way around
— Elon Musk (@elonmusk) October 21, 2026
The transition to subscriptions has accelerated since Tesla discontinued the one-time purchase option in most markets earlier this year. The recurring model improves revenue visibility and margins compared with large upfront payments. With three-quarters of North American deliveries now including FSD, the software is now an evidently large contributor to Tesla’s economics and ancillary revenue.
Geographic expansion remains important for further gains. FSD is now available in nine countries in the EU, and more than 100,000 customers have driven over 160 million kilometers. Tesla is pursuing broader EU-wide approval, with a related vote expected in December. Similar progress in additional markets could support higher attach rates beyond North America.
These results came as Tesla had a strong quarterly delivery performance of 486,532 vehicles in the quarter, which came with its largest passenger-vehicle backlog in four years. Battery supply continued to limit volume, but the company has pointed to FSD as a clear difference-maker that is helping sustain demand. As supervised capabilities improve, the attach rate will likely continue to improve.
At face value, it is a key measure of how Tesla is converting sales into autonomy progress.
Tesla’s secretive “Project Crystal Sun” gets a big green light in Texas
Tesla is building its own maps to fix Navigation issues
