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I use Windows, so I wrote a short description of how to use tesla-solar-download with Windows 11

I use WIndows 11, and the readme.md file is clearly aimed at Linux. And I prefer to not wrestle with GitHub or svn. So I did the following: I went to the link above, clicked on the green Code button, and downloaded the distribution as a ZIP file, and unzipped this into a suitable folder, which...

Yes, that explanation makes good qualititative sense. To check, I used a solar insolation spreadsheet with 5 minute summing intervals and this showed that at 38 degrees latitude south facing panels with 4 degreees of tilt gave about 1% more energy over the day of June 21 than using the 14.5...

Wayne, I'll try again. The optimal tilt angle for solar noon is latitude - declination, as I said. You're quite right that this is also the solar zenith angle: the angle of the panel normal to vertical is equal to the tilt angle of the panel plane to horizontal. Regarding the second point...

Wayne, Solar declination is not the same as elevation. Elevation = 90 + declination - latitude for the northern hemisphere. They're different coordinate systems. I think (hope) what I wrote is correct. But the meaning of your last sentence isn't clear to me, neither the phrase "below the...

This website has a simple and also a more complex equation for solar declination and shows the error by using the simple equation. To get the optimal panel tilt at solar noon, subtract the declination from the solar site's latitude.

PG&E monthly bills could jump for many customers due to new state law They're reporting on a proposal, contrary to the headline and first paragraph.

Perhaps I don't understand your system, but the idea that the CTs should be located at the inverters does not make sense from an electrical or instrumentation point of view. CT stands for Current Transducer, and it measures the electrical current. The current is the same at the GW as it is 800...

We are on TOU-C, for which the difference between peak and off peak is <10% (October through May), so I leave the PW reserve at 90% all of the time in winter. Even if you are on an EV rate plan it may make sense to raise your reserve when the multiday forecast is for stormy weather. BTW, we...

I think you need to identify the nature of your energy flows in order to see if more storage is actually useful. I ran PVWatts on Honolulu and it shows that winter (3 months) generation is about 11% below the yearly average, while summer (4 months) is about 9% higher. The other months are...

My above calculation assumed all of the panels are facing directly south, and that is the very best orientation to get peak power. BTW, for this time of year at 44 degree latitude, the optimal panel inclination would be around 66 degrees. Normally, we describe north as azimuth 0 degrees, so...

I don't suppose that you will want to hear this, but this is much more likely to be incorrectly installed current transducers than actual generation. I ran PVWatts on Rockford Maine, and even with a 45 degree roof pitch with panels oriented exactly south and ground albedo at 0.87 (meaning snow...

As yblaser pointed out earlier, the idea that smaller inverters provide better efficiency at low irradiance is technically probably true, but the effect for modern inverters is negligible. I'm not sure if the start up voltage being 35 volts is meaningful, but Delta claims MPPT operates from 50...

I also couldn't easily get anyone to provide a ManualJ calculation, so I did it myself using the nearly free software from CoolCalc. IIRC, after carrying out the calculation, I paid $10 to allow the calculation to be transferred to a PDF file. When I did this a couple of years ago, the $10...

Just in case it isn't clear, a non-bypassable charge is applied to all electric power supplied by the utility. "Non-bypassable" means that power that you send to the grid is not subtracted. So for example, if you consume 500kW in a month from the grid, and send back at other times during the...

The $10.xxx charge is not a non by-passable charge; it is instead a minimum daily charge or MDC. NBCs are a charge per kW while MDC are per day. NEM2 participants are charged the greater of the MDC or the NBC, as calculated on either a daily or monthly basis (I don't remember). BTW, all...

700 Watts is quite low for a typical AC system. Is it possible that the blower for the AC is on a backed up circuit while the compressor is not?

Use the instructions in the first paragraph of this post (and following posts) to get up to 10 days of history of string voltages and currents. In my solar panel system, I can also check the connection status of the MCIs.

The voltages reported on strings 1 and 2 of the 7.6kW inverter are implausible. But I don't think that the inverter sizes are a problem, because the generation curve shape looks normal. If you can post a single line diagram similar to this example and also the drawing that shows the placement...

Storm Ready blurb I can't recall seeing a planned development on substantially level ground that has streets higher than the houses. I think streets generally carry excess water. As the linked PDF states, they avoided the storm surge problem by building on the highest available ground, which...

If by "it", you refer to the solar production, then you already knew it could be done--your house produces annually more electricity than you use. Babcock Ranch Fact Sheet According to the fact sheet, the development has 74MW of solar capacity, and 10MW/40MWh of battery. Night time and or...

I wonder just how much credence we want to give to a tweet? I think the lower right hand picture shows the entry way to the house with an arch just to the left of the garage door. I think the PWs are just inside that entry way. The two exterior pictures of the house don't seem to show a...

I'm all for battery storage and am glad to see that Oahu is investing in storage. But the coal plant going off-line (as required by law) is 180MW, and this MegaPack installation is about 450MWh, or less than 3 hours. It won't come close to making up the shuttered coal plant. Instead Oahu will...

I agree that the PV1 voltage seems to be incorrect, implying that the system still isn't wired correctly. However, the current provided by PV1 (sept 2022) increases sharply at just before 11AM. It roughly doubles. Is one set of tiles shaded until then? Similarly, PV3 shows half current...

Nissan says that the Leaf battery is guaranteed for 8 years or 100,000 miles, presumably whichever is sooner. Let's take 100,000 miles and assume 300 Wh/mile. That means that the battery can be charged and discharged with 30,000kWh and still have (likely) 70% capacity. If we assume that in...

The solar panel fire in the OP was quite close to Glenbrook, between Grass Valley and Nevada city. I don't believe there are any vegetation fires in the vicinity. FWIW, satellite and street views suggest that this house has a number of tall trees around it, so I suppose that the installation...

From the Emporia Vue installation manual: "The wire harness allows for single-phase power and three-phase voltage sensing: White connects to Neutral, Black provides power and voltage sensing, and Blue and Red enable voltage sensing only." So at least for typical USA split phase wiring, the Vue...

To expand on BGbreeder's comments, the actual power produced by solar panels depends on the exact azimuth (where due north is 0 degrees) and roof angles. Either enter that info into PVWatts or post it here to get an estimate of expected power. Also note that high solar panel temperatures...

Wayne, here's your method. It predicts an even lower loss: For a DC/AC ratio of 1, the projected annual production is 16.089kWh. Clipping the hourly sum of the three arrays at 7.6kW give 15.707. Clipping at 11.4kW produces the same as DC/AC=1. This is about 2.4% loss. @bswood, you can...

I used the sum from a clear day in August to find a nearly equivalent single orientation solar array. Then I checked annual production at 1.12 and 1.68 for this equivalent array.

I agree your method will work-- PVWatts does give production for every hour of the year if you ask for hourly data. But I think my method is also very close. I chose a AC/DC ratio of 1.12 because that's what a possible 3.8kW plus 7.6kW remediation would give. In fact there was no clipping at...

I modeled this using August 5 as a proxy for a clear sunny day, and used 20 panels at 36 tilt, 209 AZ, 6 panels at 36 and 119, and 4 panels at 18 and 299, all at a DC/AC ratio of 1.12 Then I summed the three outputs to obtain the expected shape during the day. Then multiplied the 20 panel data...

It is my belief that a Powerwall+ can support its own PW and one other. So seemingly to support 3 PWs, the installation must include 2 inverters-- the PW+ inverter and another one to operate the third PW. Or, it needs to have at least one inverter coupled to 3 PWs (not PW+s). Perhaps it...

If I did the calculation correctly, moving 6 panels to the NW side would increase summer time production after 4PM by 2kWh on sunny days without losing any total daily production. On the other hand, in December/January there is negligible late afternoon effect, but total daily production is...

I used a different kind of calculator put out by New Mexico State University. It has quite a bit of detail not provided by PVWatts, but it isn't useful for projecting annual production--it calculates the output assuming no shading and clear weather. I augmented the spreadsheet by adding a tab...

As Redhill_qik has said, your system looks like it is performing to expectation. Just to confirm, I ran your parameters into a different solar estimator, and it gave 9kW at peak and 73kWh for June 21. The Tesla SR72T2 roof tile that is listed on your drawing has a temperature coefficient for...

Well, "pitiful" seems a bit strong to me. We installed a Mitsubishi ASHP to replace our gas furnace in January 2021. It uses air ducts just like furnaces do, with the air handler placed in the location of the furnace. We don't have back up heating, but it has been 30 years since we last had...

The report you cite is a news article. The source for the article is ADMINISTRATIVE LAW JUDGE’S RULING I don't see any suggestion that existing NEM 2.0 customers would be subject to the glide path approach.

You can get the azimuth by looking at your house in the satellite view in Google Maps and using a protractor. I checked my roof tilt by going up a ladder and using a clinometer app in my phone.

If your PW was full or nearly so at the time of the utility power outage, it may take a second or so to switch to back up power. Once it does, PWs will increase their output frequency from 60Hz to (by default) 65Hz, as a mechanism to curtail solar production. This may flummox digital clocks...

The link given by BGbreeder (a PDF file) has very detailed instructions. It is only necessary to remove the deadfront if the panel type is QO and the date code is in range and the plant is 15. See pages 25 or 26 to find how to tell if the panel type is QO without removing the deadfront. The...

I think that "impossible to export" is not enough to avoid PTO. Rule 21 D.1 says one needs an interconnection agreement for parallel operation, and parallel operation is defined as "The simultaneous operation of a Generator with power delivered or received by Distribution Provider while...

Why not? PG&E, SCE, and SDGE have a $10/month charge now.

I don't understand this. If you purchase a system, it has to be paid for, right? Are you saying they arranged a loan for you that had no down payment?

holeydonut posted this link more than a year ago (thanks!). It tells us half the story--SGIP requires: "Residential customers applying for battery storage incentives must transition to qualifying home charging rate schedules [EVA, EVB, EV2A or TOU-C (Only for Medical Baseline Customers)] in...

I believe that ETOU C is available to anyone operating up to 2 Powerwalls (more accurately <10kW discharge capability and <150% of solar capacity). We are on ETOU C with PTO on Dec 18, 2020. We don't have any EVs.

Firstly, my advice is to not mention any similarity to the symptoms/cure that I (some random guy on the interweb) had. I think it is better to describe that you're showing equal voltages and currents from your two strings, and avoid telling them how to fix it, at least at this stage. Anyway...

My experience, which is now more than a year old, suggests that it is important to concisely explain the important symptoms. Simply telling Tesla that you expected more energy or peak power output than you're seeing will probably not get a good response. In this case I would write an email to...

@notsure11, I think you are computing the PW efficiency correctly. However, there are two mechanisms contributing to efficiency loss. The obvious one is the losses in converting electric energy to chemical energy and then back to electric energy. The other loss is the energy required to run...

I simulated for lat 29.4 and long 98.5 with inclination 42degrees, assuming directly south and west. This assumes no shade and no clouds, so after 2PM the south and combined curves won't look like the graph. But you should get around 6.5kW at 1:30PM if the system is working correctly. I...