News
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 Roadster’s new patent preps white-knuckle speeds, keeping it grounded
Ahead of its highly anticipated unveiling, Tesla’s upcoming Roadster received a new patent that aims to keep it grounded while enabling white-knuckle speeds.
The patent, which was granted on September 29, is titled “Electric Car Fan,” bluntly stating its design but not its purpose, which is further detailed in the text of the application. Interestingly, it comes two weeks before the Roadster event, which was delayed due to unfavorable weather on Thursday, which could cause issues, as Tesla revealed the event must be held outdoors.
🚨 The design uses electrically driven ducted fans, typically shown as a row of four at the rear, powered by the vehicle’s high-voltage battery.
The fans pull air from an underbody inlet, route it through ducts, and expel it from a larger rear outlet that functions as a… https://t.co/CHQB9u9UA3 pic.twitter.com/QVXmWTdggh
— TESLARATI (@Teslarati) September 29, 2026
The purpose is to solve a problem that is relatively unique to high-performance electric cars. Instant motor torque is useless if the tires cannot plant that force, and conventional wings and underbody tunnels generate downforce only when air is already rushing past the car. At launch, in slow corners, and under hard braking from modest speed, passive aerodynamic additions contribute essentially very little to downforce.
Tesla’s filing says that its fans can produce the downforce needed, independent of vehicle velocity, then ease off so the same hardware does not pile on drag at highway speeds, an issue that can come from excessive body modifications.
The hardware outlined in the patent is a ducted-fan package that is placed into the rear of the vehicle. An underbody inlet between the rear wheels feeds a duct that rises to a wide outlet in the diffuser. In that outlet are four axial fans, which are divided by vertical strakes. They will pull air from under the floor and press the chassis onto the pavement.
The language in the patent claims it can cut drag rather than add to it while simultaneously increasing downforce.
Tesla Roadster event requires restricted airspace, and the FAA obliges
The fans run from the high-voltage battery and a vehicle control system, so output can be modulated rather than left on as a fixed penalty.
There are additional strengths that can come from this design, like extra tire load at low speed, which can contribute to even more face-melting acceleration rates, decrease stopping distance, and sharper turn-in before a wing has air to work with. Adjustable fan speed lets the car add grip only when needed, so it can be catered to the force of a turn or acceleration.
These designs were previously used, and banned, in some competitive settings. The Brabham BT46B was banned in F1 competition for using a similar fan design and being labeled as too effective.
Tesla still lists the Roadster as having a sub-two-second 0-60 MPH time and a 250-plus-MPH top speed, and there are expectations for a SpaceX cold-gas thruster package that could not only increase acceleration but potentially cause the vehicle to hover.
It is important to note that a patent is not a production part, and packaging four fans in a rear diffuser, managing noise, and potential debris are all things Tesla must consider. With that being said, the patent being granted shows Tesla is designing the Roadster to go fast, but it is also attempting to use unique strategies to combat any issues it might have at those speeds.
Investor's Corner
Tesla showrooms picked clean ahead of Q3 end as demand looks strong
Tesla (NASDAQ: TSLA) showrooms have been picked clean ahead of the end of the third quarter of the year, as demand looks to be strong and delivery estimates for new vehicles are pushed into late 2026 and early 2027.
Tesla appears to have sold out of many of its Model 3 and Model Y trim levels in the United States, as only the Model Y RWD and Model Y All-Wheel-Drive are available for delivery before the end of the year.
Additionally, many showrooms are either completely empty or void of all but just one demo unit within the buildings themselves in an effort to bolster what could be one of Tesla’s best quarters in vehicle deliveries in recent memory.
I’m at Tesla right now and when I walked into their showroom I was shocked to see it basically empty.
I asked one of the people working there where all of the cars are “Gone – it’s the end of the quarter and we’ve sold out of everything… including the display vehicles”So… pic.twitter.com/rN7s3gE6sJ
— Devin Olsen (@DevinOlsenn) September 25, 2026
All the cars are gone from Tesla Century City!
All they have is Model Y L, a self-driving video playing on the background. I guess the best product is no product. Either that or they just sold the showroom cars. pic.twitter.com/mzCjWaXwww
— Whole Mars Catalog (@wholemars) September 26, 2026
Show room is empty. I asked and they have sold the demo cars too. Delivery numbers better be outstanding! pic.twitter.com/jq5N28Q6tZ
— Electric Brawl (@3lectricBrawl) September 22, 2026
Additionally, when I spoke to the guys at Tesla Mechanicsburg two weeks ago, when I returned the Model Y L, their third hauler of the week had just arrived, and every vehicle on it, along with every vehicle in their delivery lot, was accounted for and had a name attached to it for delivery.
Talking to the guys at the Mechanicsburg showroom on Friday, they couldn’t believe they had ANOTHER hauler coming in of cars for delivery—and each was accounted for
No car just sitting in inventory. They’re expecting a BIG quarter, and this is more than just the Y L https://t.co/ce801GkKVv
— TESLARATI (@Teslarati) September 21, 2026
Tesla saw a 25 percent increase in deliveries in Q2 compared to the same quarter the year before. The vast majority of the 480,126 units it delivered, 467,762 vehicles to be exact, were the Model 3 and Model Y.
In Q3 2025, Tesla delivered 497,099 vehicles, once again a figure that was dominated by the company’s two mass-market vehicles. Analysts have unusually wide predictions for this quarter, likely because so many firms missed the Q2 delivery figure by such a substantial margin; Wall Street predicted 408,000 cars, while Tesla delivered 480,000.
Goldman Sachs has Tesla slotted for 435,000 deliveries in Q3, while JPMorgan said it anticipates 482,000. The median guess is about 449,000 deliveries for Q3.
Interested in ordering a Tesla? Use my referral code for three free months of Full Self-Driving (Supervised) here.
Lifestyle
Watch Tesla’s “guardian angel” FSD feature take over for collision evasion
Tesla’s Automatic Collision Evasion feature can be seen in one of the first owner videos of it in action.
Tesla owner Spencer (@scotsrule08) posted on Monday that the feature “worked flawlessly,” saying FSD reengaged itself just as he was about to hit a curb. Ashok Elluswamy, who leads Tesla’s AI team, shared the clip and wrote, “A guardian angel always looking out for you.”
The video arrives in the middle of a staged rollout. Tesla first shipped Automatic Collision Evasion with FSD (Supervised) v14.3.9 in software update 2026.27.6 earlier this month, which Teslarati covered as it reached cars. Update 2026.27.10, which began going out on September 19, carried the feature improvements with FSD v14.3.10, according to release notes tracked by Not a Tesla App. The newer 2026.27.11 build is now reaching another wave of vehicles.
The new Automatic Collision Evasion feature worked flawlessly! FSD reengaged itself just as I was about to hit a curb.
Kudos @Tesla_AI team! 👏 pic.twitter.com/Fbp15HhpL2
— Spencer (@scotsrule08) September 28, 2026
The feature only runs on HW4 vehicles, and it requires an active FSD purchase or subscription with both FSD (Supervised) and Automatic Emergency Braking enabled. HW3 owners receive FSD v14.2 Lite in the same updates, but that build does not include collision evasion.
Tesla’s release notes describe two triggers. The first is an imminent frontal collision that braking alone may not prevent, in which case the car can activate FSD to steer, brake or accelerate around the hazard. That scenario is limited to highways below 85 mph, with no pedestrians or cyclists detected and no slippery road surface. The second covers a driver who appears inattentive, such as reaching into the back seat, or who seems to have switched off FSD by accident. Spencer’s curb clip appears to fall into that second category.
Tesla plans big safety improvements for Full Self-Driving v15
Once the system takes over, the accelerator is muted and light brake input will not cancel the maneuver. Drivers need to apply firm, deliberate steering force to take back control, and the car chimes to hand control back once the danger has passed.
Elluswamy recently noted that earlier hazard prediction, faster reaction time and better collision avoidance would arrive with FSD v15, the next major version.







