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.
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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.
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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.
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News
Tesla is improving Giga Berlin’s free “Giga Train” service for employees
With this initiative, Tesla aims to boost the number of Gigafactory Berlin employees commuting by rail while keeping the shuttle free for all riders.
Tesla will expand its factory shuttle service in Germany beginning January 4, adding direct rail trips from Berlin Ostbahnhof to Giga Berlin-Brandenburg in Grünheide.
With this initiative, Tesla aims to boost the number of Gigafactory Berlin employees commuting by rail while keeping the shuttle free for all riders.
New shuttle route
As noted in a report from rbb24, the updated service, which will start January 4, will run between the Berlin Ostbahnhof East Station and the Erkner Station at the Gigafactory Berlin complex. Tesla stated that the timetable mirrors shift changes for the facility’s employees, and similar to before, the service will be completely free. The train will offer six direct trips per day as well.
“The service includes six daily trips, which also cover our shift times. The trains will run between Berlin Ostbahnhof (with a stop at Ostkreuz) and Erkner station to the Gigafactory,” Tesla Germany stated.
Even with construction continuing at Fangschleuse and Köpenick stations, the company said the route has been optimized to maintain a predictable 35-minute travel time. The update follows earlier phases of Tesla’s “Giga Train” program, which initially connected Erkner to the factory grounds before expanding to Berlin-Lichtenberg.
-->Tesla pushes for majority rail commuting
Tesla began production at Grünheide in March 2022, and the factory’s workforce has since grown to around 11,500 employees, with an estimated 60% commuting from Berlin. The facility produces the Model Y, Tesla’s best-selling vehicle, for both Germany and other territories.
The company has repeatedly emphasized its goal of having more than half its staff use public transportation rather than cars, positioning the shuttle as a key part of that initiative. In keeping with the factory’s sustainability focus, Tesla continues to allow even non-employees to ride the shuttle free of charge, making it a broader mobility option for the area.
News
Tesla Model 3 and Model Y dominate China’s real-world efficiency tests
The Tesla Model 3 posted 20.8 kWh/100 km while the Model Y followed closely at 21.8 kWh/100 km.
Tesla’s Model 3 and Model Y once again led the field in a new real-world energy-consumption test conducted by China’s Autohome, outperforming numerous rival electric vehicles in controlled conditions.
The results, which placed both Teslas in the top two spots, prompted Xiaomi CEO Lei Jun to acknowledge Tesla’s efficiency advantage while noting that his company’s vehicles will continue refining its own models to close the gap.
Tesla secures top efficiency results
Autohome’s evaluation placed all vehicles under identical conditions, such as a full 375-kg load, cabin temperature fixed at 24°C on automatic climate control, and a steady cruising speed of 120 km/h. In this environment, the Tesla Model 3 posted 20.8 kWh/100 km while the Model Y followed closely at 21.8 kWh/100 km, as noted in a Sina News report.
These figures positioned Tesla’s vehicles firmly at the top of the ranking and highlighted their continued leadership in long-range efficiency. The test also highlighted how drivetrain optimization, software management, and aerodynamic profiles remain key differentiators in high-speed, cold-weather scenarios where many electric cars struggle to maintain low consumption.
Xiaomi’s Lei Jun pledges to continue learning from Tesla
Following the results, Xiaomi CEO Lei Jun noted that the Xiaomi SU7 actually performed well overall but naturally consumed more energy due to its larger C-segment footprint and higher specification. He reiterated that factors such as size and weight contributed to the difference in real-world consumption compared to Tesla. Still, the executive noted that Xiaomi will continue to learn from the veteran EV maker.
“The Xiaomi SU7’s energy consumption performance is also very good; you can take a closer look. The fact that its test results are weaker than Tesla’s is partly due to objective reasons: the Xiaomi SU7 is a C-segment car, larger and with higher specifications, making it heavier and naturally increasing energy consumption. Of course, we will continue to learn from Tesla and further optimize its energy consumption performance!” Lei Jun wrote in a post on Weibo.
-->Lei Jun has repeatedly described Tesla as the global benchmark for EV efficiency, previously stating that Xiaomi may require three to five years to match its leadership. He has also been very supportive of FSD, even testing the system in the United States.
Elon Musk
Elon Musk reveals what will make Optimus’ ridiculous production targets feasible
Musk recent post suggests that Tesla has a plan to attain Optimus’ production goals.
Elon Musk subtly teased Tesla’s strategy to achieve Optimus’ insane production volume targets. The CEO has shared his predictions about Optimus’ volume, and they are so ambitious that one would mistake them for science fiction.
Musk’s recent post on X, however, suggests that Tesla has a plan to attain Optimus’ production goals.
The highest volume product
Elon Musk has been pretty clear about the idea of Optimus being Tesla’s highest-volume product. During the Tesla 2025 Annual Shareholder Meeting, Musk stated that the humanoid robot will see “the fastest production ramp of any product of any large complex manufactured product ever,” starting with a one-million-per-year line at the Fremont Factory.
Following this, Musk stated that Giga Texas will receive a 10 million-per-year unit Optimus line. But even at this level, the Optimus ramp is just beginning, as the production of the humanoid robot will only accelerate from there. At some point, the CEO stated that a Mars location could even have a 100 million-unit-per-year production line, resulting in up to a billion Optimus robots being produced per year.
Self-replication is key
During the weekend, Musk posted a short message that hinted at Tesla’s Optimus strategy. “Optimus will be the Von Neumann probe,” the CEO wrote in his post. This short comment suggests that Tesla will not be relying on traditional production systems to make Optimus. The company probably won’t even hire humans to produce the humanoid robot at one point. Instead, Optimus robots could simply produce other Optimus robots, allowing them to self-replicate.
-->The Von Neumann is a hypothetical self-replicating spacecraft proposed by the mathematician and physicist John von Neumann in the 1940s–1950s. The hypothetical machine in the concept would be able to travel to a new star system or location, land, mine, and extract raw materials from planets, asteroids, and moons as needed, use those materials to manufacture copies of itself, and launch the new copies toward other star systems.
If Optimus could pull off this ambitious target, the humanoid robot would indeed be the highest volume product ever created. It could, as Musk predicted, really change the world.
Tesla is improving Giga Berlin’s free “Giga Train” service for employees
Tesla Model 3 and Model Y dominate China’s real-world efficiency tests
