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In theory that's what it does now. It's using solar forecasts, which should account for weather. It still does seem to optimize for self-consuming solar rather than storing it in the battery, though. As a result, my Powerwalls often seem to fill up before the afternoon shoulder/peak period...

They probably don't require power to your house, but they do require power to their networking equipment in your neighborhood. This equipment probably is affected by the same power outage. Supposedly optical fiber service is generally less susceptibly to these failures since a larger part of the...

I believe that if both of your solar systems are fed into the gateway the ZigBee boxes should no longer be needed. My understanding is the ZigBee boxes were originally used to send the inverter data to Tesla to monitor solar generation. I have a third-party-installed solar system hooked to a...

I think it may be worth taking a step back. Prior to the IRA, the statute for the ITC only said renewable energy systems were eligible for the credit. So the question was whether a battery was part of the renewable energy system if it was installed after the solar system. The Private Letter...

This only applies to commercial installations, not residential. For residential, the reference is an IRS letter that says that in their opinion the law intended only to allow batteries 100% charged from solar. There is no mention of an ITC claw-back for residential projects either, so it's...

FWIW, according to the release notes Tesla added the consideration of solar forecasts to the charging behavior in version 22.26 (released September 2022). Here in the US, it does seem to work. My Powerwalls charged to nearly full overnight the past two days when it was raining. The forecast for...

Based on data returned by the API, the current EV charging setting seems to do the charging control using frequency shifting. Obviously this can only happen when the grid is down, so they'll have to come up with a new way of communicating for this feature. The frequency shift is clever, since...

The production cap is even a little worse than it sounds. Not only are you disallowed the overage, but if you're on a TOU plan, PG&E subtracts the excess export from the highest rate first, even if the excess happened during a lower rate period. This means you really don't want to run into this...

In theory, solar should shut off when the PW is full and the grid is down - the Powerwalls shift frequency to shut the solar down. If you actually had 3.6kW with nowhere to go, you'd probably notice the smoke...

The Wh numbers the API returns for pack energy and current charge do not reflect this. My personal guess is they minimize charging at a high SOC to avoid battery degradation. Doesn't backup-only do something similar? I seem to remember that it also would let the charge float down to 97% before...

min_site_meter_power_kW is the export limit. The Powerwalls will limit exports to stay under this total export number for the site. Presumably max_site_meter_power would be the import limit, and the Powerwalls would attempt to keep the site imports less than that amount. nominal_system_power_kW...

My site was limited to 8kW when I first checked some time back. When they enabled export everything, the limit was removed so I could export at 10kW. They added the export limit back at 7.8kW when I signed up for the VPP a little later. The timing could be coincidence, though.

I miss the Tesla loss-leader days when they charged me $900 to install two Powerwalls and tie them to an existing solar system.

There was a period where Tesla used SolarEdge inverters. See other threads on this board about people's troubles with them. I think Tesla no longer uses SolarEdge inverters, so current installs should be much less likely to have this problem.

Actually, I think it will cut off power coming from the meter to the Tesla Energy Gateway. This will disconnect your house from the grid.

Hmm, for me the energy graphs reflect what the energy flow shows in realtime. Here is a chart of the home load for the same day from an external system that monitors the flow reported on the Gateway's web page (i.e. the numbers you see when you log into the Gateway):

If I understand your issue correctly, I do not have this problem when charging from the grid. My house load still shows correctly when charging from the grid. Here's last Sunday's grid use graph. Note the grid charging at midnight and around 2pm with house load drawing from the grid.

FWIW, Home Assistant has a Tesla Powerwall integration that includes a grid status binary sensor that can be used to trigger other devices such as smart plugs. The drawback with a software-only approach is it is a little more fragile as I found out yesterday when some kind of glitch (maybe power...

If you're going to be playing around with automation, I recommend checking out the pyPowerwall proxy. It handles authentication and decoding some of the more complex data coming back from the local API (the binary data in /vitals, for example). pypowerwall/proxy at main · jasonacox/pypowerwall

Here's a solar tariff document that I found for Pacific Power: https://www.pacificpower.net/content/dam/pcorp/documents/en/pacificpower/rates-regulation/oregon/tariffs/rates/135_Net_Metering_Service_Optional_for_Qualifying_Customers.pdf In particular, under "Special Conditions" here is a...

That's an interesting data point. Have you checked to see whether both batteries show the same degradation (e.g., using the local /api/system_status)?

This was definitely not true in the past. The reason why Ohmconnect wasn't compensated was because the demand-reduction program they were bidding on treats all negative numbers as 0, irrespective of magnitude. I don't know if this has changed in the newer programs, since the ELRP now does...

I don't believe this requirement applies any more now that batteries are listed explicitly in the tax credit: https://www.irs.gov/pub/taxpros/fs-2022-40.pdf So, for new installations the credit should apply whether the batteries are charged from the grid or from renewables, as long as they're...

The short answer is yes to both. The caveat is that not everybody gets grid charging enabled depending on the interconnection agreement with the utility and Tesla's interpretation of tax rules. The discharging during peak rate periods is a standard part of Tesla's time-based control setting...

Interesting, the verbiage on the program description doesn't make this clear at all. I know Sunrun also participated in the ELRP program last year. I'm still confused why there would be any events at this time of year, though.

I didn't think Power on Peninsula is a VPP program, are you sure about this? From my reading, Power on Peninsula is just a $500 rebate for customers referred to Sunrun by PCE. There shouldn't be any VPP events at this time of year in California, so even if you were enrolled in one I wouldn't...

The program that the Tesla VPP is a part of is the Emergency Load Reduction Program. Its season is May through October. Here is a page on the CPUC site describing the program (not yet updated for 2023): Emergency Load Reduction Program ELRP events are strongly weather-dependent due to AC usage...

My 2018 vintage Powerwalls neither charged above regular 100% in Stormwatch nor showed any change in maximum charge (as reported by the API) after charging in Stormwatch during the last storm. I do see minor differences in maximum charge depending on depth of discharge. I normally run TBC with...

The Federal Investment Tax Credit (aka Solar Credit) prior to the current revision required the batteries to be 100% charged from a renewable source in order to be eligible. There doesn't seem to be any clear indication of how long the batteries need to be charged from solar before grid charging...

Good point. I overlooked that your reserve was set to 50%. I'm guessing it's a provisioning issue on Tesla's side and the system is not correctly set up to be controlled by your account (or is being controlled by another account as well). I vaguely remember somebody having similar issues on a...

It doesn't sound like VPP. It sounds like somehow your Powerwalls are resetting to time-based control, with export everything turned on. The behavior you're describing exactly matches that mode.

I have a Gateway 1 and two of my Neurio CTs measure solar and two measure the site feed. As I understand it, Gateway 2 has built-in CTs (visible above the breaker in your picture), so you don't need the Neurio to measure your site loads unless you have loads outside of the Gateway. In addition...

Not as such. The only API available is the one used by the mobile app, so you can only change modes to the ones supported by Tesla. If you have “export everything” enabled, you could probably configure a peak period to get close to the right behavior, but you’d have no direct control over the...

I don't see how you can participate if Tesla isn't involved. There isn't a user setting that will export a fixed amount of power during a certain period. This currently would have to be initiated from Tesla's servers, like the VPP is.

You can definitely bypass the app by querying the Powerwall's local web API. See this example: GitHub - jasonacox/Powerwall-Dashboard: Grafana Dashboard for Tesla Powerwall However, note that this isn't "open-source." It's simply using the same API the local web GUI uses. This means it's subject...

It is very likely that the operation of Powerwalls is different in different countries. It may also vary depending on whether you have solar or not. I'm in the US and have solar, and my Powerwalls will not charge at more than 1.6 kW each unless they are above the backup reserve in TBC. The...

I'm a little suspicious these measurements are just rough estimates. My system was installed two weeks earlier: "nominal_full_pack_energy": 27652 "PackagePartNumber": "1092170-03-G" "nominal_full_pack_energy": 13850 "energy_charged": 7773100,"energy_discharged": 6664120 "PackagePartNumber"...

Give it some time. Given that the new credit is available for batteries without solar, I expect the restriction on grid charging to be relaxed next year. FWIW, my grid charging was enabled automatically when the feature was released, even though I took the ITC. The policy is not as set in...

Since you have solar and are overproducing, you're fine on ETOU-C. EV2-A can be advantageous with solar and batteries if you're paying money at true-up because you can charge during off-peak and then export during peak to generate more NEM credits. Since you'll have extra credits that expire...

If you're grid charging to charge up to your backup reserve, this is true. However, if you're in time-based control mode and the Powerwalls decide they need to grid charge, they'll go up to 5 kW each. In the screenshot below, my setting used the backup reserve at midnight to reach a set level...

You might also want to check out EV2A. EV2A is available on a pilot basis to customers with batteries, even if you don't have an EV. The main question is whether you expect to pay money at true-up or not. If you're going to overproduce, the price differential gives you very little real benefit...

Subtracting $.03 from the sell price should work. When you do this, the Powerwall algorithm should prefer using solar to feed house load to exporting. This means that it will switch to using only excess solar to charge if it thinks it will reach 100% before the off-peak period ends, for example...

I see. My impression is the Powerwalls only look ahead one day for their planning. I'm not 100% sure of this though. In other words, they won't try to plan for the weekend until Friday. Have you set a difference between the sell and buy prices in your rate plan to account for non-bypassable...

If you're on time-based control, the system assumes that you want to export as much solar as possible during peak rate periods in order to maximize your credit. If you don't want this, you can switch to self-consumption where the batteries just cover any excess demand. That way the batteries...

How thick are the clouds? I have a SW-facing array and in the mornings before the direct sun shines on the panels I get slightly more production with light cloud cover than with clear skies. Your numbers sound pretty extreme, though, so there may still be a measurement error somewhere.

I'm using the EV2-A rates - $.43 peak, $.41 partial-peak and $.25 off-peak. If I turn off "export everything," my house is powered from the batteries through partial peak and peak. If your only goal is for the Powerwalls to discharge at the right time, you could just pick arbitrary numbers like...

Moreover they subtract credits from the highest rate first, so if the extra exporting happens off-peak it'll end up reducing your credits that cycle.

That does sound strange. What is your backup reserve set to now? The other place I would check is the rate plan. I wonder if something is misconfigured there that might be confusing your system.

Sorry, I'm not clear on what you want to happen. Do you want your Powerwalls on backup only, or do you want to self-consume your solar? I'm not sure that there is a mode that allows you to self-consume only the amount of solar you're producing each day (i.e., self consume but have the Powerwalls...

I have evidence that the algorithm does not do this on an intraday basis. There was one day where I had 22.7 kWh of solar production and 27.2 kWh of grid export. Since the export limitation is enforced on a billing cycle there is still a possibility that the algorithm might do something on a...