Merrill
Merrill
This was my issue but have not figured a way to lower grid usage other than what I have set TBC cost savings and set peak 4pm to 9pm. I have tried other settings but do not want to go from 100% to 15% everyday.
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Are these operating modes possible?
- Thread starter RKCRLR
- Start date
Yesterday I had Shoulder (Balanced) set to 4-9pm. and everything else Off-Peak At 4pm it started sending all solar to the grid, none to the house, had ran the house off the Powerwalls. At 9pm it started running off the grid with the Powerwalls at about 75% SoC. Before I went to bed, I switched the Shoulder period to be 8am to 9pm. The Powerwalls stayed at about 75% SoC until the solar started generating in the morning - then all solar was being sent to the Powerwalls. At 8am the house started running off the Powerwalls with all solar being sent to the grid. This continued until I hit my 50% reserve around noon, then the house was running off solar with the excess going to the grid and non to recharge the Powerwalls. At 2:30 I intervened and changed back to Cost Savings with 4-9pm Peak and all else Off-Peak in hope of getting as much SoC back before 4pm Peak rates hit.
So, for me, Balanced Shoulder does not prioritize the house (which is what I wanted) until I hit my reserve but I have the downside of the house running off the Powerwalls during Off-Peak.
skepticcyclist
Member
It does but you also have to have a peak period set. If you only have shoulder then it will treat shoulder like peak. I have shoulder from 4:00-7:30 then peak from 7:30-9:00. Doing this will prioritize shoulder like advertised. When I set shoulder as 4:00-9:00 with no peak, then shoulder acted like peak
I tried Shoulder from 4-8pm and Peak from 8-9pm (see post #64). The problem was it was drawing supplemental power from the grid during Shoulder when the solar couldn't keep up with the house demand.
Yep, that is where I was but I thought I'd give Balanced mode a fair chance. I'll likely wind up back on Cost Saving mode with Peak set from 4-9 pm and Off-Peak all other times.
Sorry, that didn't work. It seems trying to trick it one direction causes a problem in a different direction. I was trying to force the surplus only charging with the park peak but that made the system want to charge aggressively during the off peak.
I think going back a schedule similar to @skepticcyclist 's schedule might work for you, so something like this:
Balanced
Off peak: 9:00 pm to 4:00 pm
Part peak: 4:00 pm to 8:00 pm
Peak: 8:00 pm to 9:00 pm
When you tried this before the problem was part peak was drawing from the grid when the solar couldn't keep up. I believe @h2ofun was making a point about trying it for a few days. I don't recall if you tried that. My model of the system is that it wants to have enough energy to cover the peak period. I interpret the behavior that you saw then as indicating the system didn't think it had enough energy to ride through peak. This might be the closest option for now.
Also remember that this is probabilistic game. The system can't actually know how much consumption and generation will happen so you will have to accept some error.
What is the need for park peak? Yep, I never saw his do something and leave it for a week so the program could learn.
I am 99% off the grid, meaning batteries are used 100% when no solar, help solar when it starts, and then none once solar is up and running. Perfect unless you are worrying about using the batteries. If so, just buy a generator and not batteries.
The first need is to match tariffs. This in practices seems to allow the system to prioritize when to use stored energy. When I had less battery and PV the system would try to make sure that the peak was covered. *IF* it thought there was going to be enough stored "off peak" energy it would cover some of it. This in theory maximized savings. This was particularly complex when most of the "part peak" occurs before the "peak". Does the system discharge the battery during the "part peak" and make a little money but run the risk of running out during "peak" or does it hold on it? If it does hold it might ending holding too much and then it missed a savings opportunity for that energy.
Good points. What I can do in the summer will probably be different than what I will need to do in winter. All fun and games.
Changing all your solar generating hours from Off-Peak to Shoulder is a drastic change. I would either try leaving the morning Off-Peak or giving it a few days to learn the new schedule. Clearly it can't drain the batteries during shoulder solar generating hours and still have enough for Peak. It will have to change the way it operates on that schedule. It is a learning system and will change.
I might try Balanced with Shoulder from 4-8pm and Peak from 8-9pm again and try to leave it alone for a few days. Its just really hard to watch the house running from the grid during peak hours and running off the Powerwalls off-peak. But I think it is reasonable to think that if the system isn't trending for what I'm looking for after a few days it isn't going to get there.
Just for grins, I'm going to try Cost Saving with Shoulder set to 4-9pm (my peak hours). According to the documentation this should act just like Peak but things haven't been working quite like the documentation suggests they should so far.
Cost Saving with Shoulder set to 4-9pm and 50% reserve worked just as expected.
From 4-9pm the house ran off the Powerwalls and all solar was sent to the grid. At 9pm the house started running off the grid with the Powerwalls at 80% SoC. The Powerwalls remained at 80% SoC until solar started producing in the morning (this is exactly how I want them to operate off-peak when no solar is being produced). When the solar started producing most of the solar was going to the Powerwalls (there was a small amount of solar being diverted to the house) until the Powerwalls were fully recharged a little after 9am. If solar was prioritized to the house over the Powerwalls during off-peak and to the house over the grid during peak this operating mode would be perfect.
I'm going to try Balanced again for three days (unless some think 3 days isn't enough) since some people don't think I gave it enough time.
I'm going to set Shoulder to 4-8pm and Peak to 8-9pm unless there are better settings to see if I can achieve my goal.
From 4-9pm the house ran off the Powerwalls and all solar was sent to the grid. At 9pm the house started running off the grid with the Powerwalls at 80% SoC. The Powerwalls remained at 80% SoC until solar started producing in the morning (this is exactly how I want them to operate off-peak when no solar is being produced). When the solar started producing most of the solar was going to the Powerwalls (there was a small amount of solar being diverted to the house) until the Powerwalls were fully recharged a little after 9am. If solar was prioritized to the house over the Powerwalls during off-peak and to the house over the grid during peak this operating mode would be perfect.
I'm going to try Balanced again for three days (unless some think 3 days isn't enough) since some people don't think I gave it enough time.
I'm going to set Shoulder to 4-8pm and Peak to 8-9pm unless there are better settings to see if I can achieve my goal.
Day 1 of Shoulder set to 4-8pm and Peak to 8-9pm in Balanced mode results:
During the day the house was running off solar with the excess going to the grid (good).
At 4pm the house continued to run off solar with excess going to the grid (good).
Around 7pm the solar couldn't keep up with the house demand and excess was being drawn both from the grid (bad) and the Powerwall (good).
At 8pm all power was coming from the Powerwalls (good).
At 9pm the Powerwalls were still over 90% SoC but then the house began running off the Powerwalls throughout the night (bad).
Around 7:30am the Powerwalls were down to 55% SoC when the solar started generating. The house was then running off the solar with the excess going recharging the Powerwalls (good) until around 11am when the Powerwalls were fully recharged.
So far, this is almost the opposite of what I'm looking for (I don't want it pulling from the grid during peak hours and running off the Powerwalls at night).
During the day the house was running off solar with the excess going to the grid (good).
At 4pm the house continued to run off solar with excess going to the grid (good).
Around 7pm the solar couldn't keep up with the house demand and excess was being drawn both from the grid (bad) and the Powerwall (good).
At 8pm all power was coming from the Powerwalls (good).
At 9pm the Powerwalls were still over 90% SoC but then the house began running off the Powerwalls throughout the night (bad).
Around 7:30am the Powerwalls were down to 55% SoC when the solar started generating. The house was then running off the solar with the excess going recharging the Powerwalls (good) until around 11am when the Powerwalls were fully recharged.
So far, this is almost the opposite of what I'm looking for (I don't want it pulling from the grid during peak hours and running off the Powerwalls at night).
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I don't - It was a typo - It was pulling from the Powerwalls during 8-9pm - fixed the typo.
Pull the start of the Peak period earlier to avoid the grid pull. When the SOC is really high, Balanced will use PW energy during Off Peak. This is one thing that I wish had a setting to completely block. Since I'm on PG&E EV2-A I don't mind the PWs draining between 9pm and midnight because that is the Part Peak rate and the vast majority of my generation happens during Off-Peak before 3pm.
This chart is typical for my system this time of year. I would like to avoid the morning discharge, but it's not a lot of energy. It's almost like it goes into a Self-Powered like mode as soon as the solar starts generating. You can also clearly see that it is not regulating the PW discharge as tightly during the nighttime Part Peak as it does during Peak. During usage spikes the discharge does not follow closely, resulting in some grid draw.
This chart is typical for my system this time of year. I would like to avoid the morning discharge, but it's not a lot of energy. It's almost like it goes into a Self-Powered like mode as soon as the solar starts generating. You can also clearly see that it is not regulating the PW discharge as tightly during the nighttime Part Peak as it does during Peak. During usage spikes the discharge does not follow closely, resulting in some grid draw.
My Balanced mode schedule exactly follows the PG&E EV2-A rate schedule 7 days a week. Peak 4-9pm, Off-Peak midnight-3pm. Shoulder other times.
Have you tried “Self Powered”? This is what our system behaves like.
As generation kicks in in the morning, it starts feeding the house (with batteries supplying remainder). Once solar can take over fully, any remainder goes to batteries. Eventually batteries charge to full, and solar feeds house and grid.
As the sun starts going down, solar + batteries are used, eventually switching to battery only. There’s no time-based control (peak etc) but it’s not necessary if you have enough battery to get you at least through the peak period.
