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Not sure if I can do a diversion load with my setup, but one of the ideas I had for something like that was LED grow lights for lettuce or other crop you don't want to expose to rat lungworm and other outside pests. Assuming some amount of natural light is available so that the light isn't required for growth but certainly goes into high gear when the lights are on. If "excess" energy can't be stored, convert it into food.
ETA: The "diversion" I'm currently using is to run the deep freeze during the day. It's on a timer so the unit doesn't try to kick on at night when there is no solar. The energy is "stored" thermally. During the 16 hours the freezer is not powered the temperature usually doesn't rise more than about 12 degrees. I have it turned up to maximum cold so that at its warmest it is usually in the single digits.
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"Maybe we have the same controller"
I missed the section about the Tracer. I have the 30amp model. I was able to get a few at 50% off so I'm running two of them.
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What I aspire to is to have 1/3 of my panels pointed east, 1/3 pointed west, and 1/3 pointed south, all at a steep angle at least 45 degrees from horizontal. I already have 1/3 pointed south south-east at about 45 degrees and the remainder up on the roof about 15 degrees from flat pointing south south-east. The goal is "virtual tracking". Some will be productive in the morning, some in the afternoon. The south angled panels will angled right for the winter sun. In the summer the east and west facing panels will start pumping out power long before and after the south facing panels even get any sun. This only works if you invest heavily on panels. Certainly you should never spend any money on trackers or even fancy fixed supports if that money could be spent on buying and mounting another panel to an available fixed surface.
This strategy has merit even where the sun shines brightly. Here in Puna where there are so many clouds, it almost doesn't matter where the panels are pointed as long as there is a clear line of sight to some part of the sky. I have been outside on a cloudy day when the brightest part of the sky was to the north simply because the clouds were thinnest there. On such days square footage of panels trumps everything else. With this setup the charge controller would never see the sum of all the attached panels because they are all generating at different times, except on cloudy days when the sky was uniformly gray. Those days are not a problem for other reasons.
I have a regular electric resistance 240 volt AC water heater as my diversion load. My charge controller turns it on when battery voltage is above 55 volts (float voltage) and off when it drops to 54 volts. I run it on 120 volts AC so it draws a little over 1,000 watts instead of the 4,500 watts listed on the nameplate. I could also run it on 55 VDC and get about 500 watts diversion load. I don't think that an electric resistance load cares about AC vs DC although the switch contacts would.
ETA: If this is a diversion load you could take the 95VDC coming directly from the panels before it goes through the charge controller and send it to the water heater. The resistance element wouldn't care what voltage it was getting. Wattage would be somewhere between 500 and 1,100 watts, probably slightly less than if powered by 120VAC. Not sure if there are any real benefits to this though.
Pro # 1. Would never draw from batteries. The way I have it set up now the inverter faithfully draws from the batteries to make the AC that runs the heater until the programmed delays run out.
Pro # 2. Less load on the inverter.
Con # 1. DC is harder to switch than AC.
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That’s a great setup markp [8D] 45 degrees in each direction is pretty dang steep though! At 30 degrees off axis the solar radiation available to the panel is 50% of optimum, so 30 degree total separation between sub arrays should roughly achieve a max output of one in any condition. A flat panel usually has a slight advantage over an angled one in cloudy conditions, giving you a nice bonus when reducing the difference in subarray angles [8D]
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If batteries were cheap I would just put everything at whatever the angle was that gave me the most Kwh for the day and store it. Panels tend to be cheaper now so virtual tracking is used to spread out the PV production so more of the power is used as it is produced, both earlier in the morning and later in the afternoon.
The sine of 30 degrees is .5. That would correspond to the panel being 60 degrees from horizontal. Two panels leaning against each other with each panel forming one leg of an equilateral triangle would produce the same power as a single panel laying flat if the sun were directly overhead. My brother, being an astronomer, drones on about "atmospheric extinction" and how that makes it unproductive to put the panels that steep but part of the problem is how to fit that many panels on your roof to get sufficient power when the sky is cloudy but at the same time not get too much power (having bought all those panels) when it is clear. With all those panels you won't suffer too much from attenuation due to the sun passing through so much atmosphere when it is clear. You will make it up rapidly when the sun gets a little higher. Also on cloudy days the light is coming from the clouds which are very near so extinction is not so much an issue.
It all depends on the relative cost of panels vs batteries. If I had infinite storage I would save energy in the summer for use in the winter. As it is on any day that your charge controller goes into float, you would have benefited from trading overall production for earlier/later production.
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Thanks everybody for sharing their experiences. If my nearly 6-year old Kirkland deep-cycle battery could bastardize a late-night commercial in the near future it would probably be "My voltage has fallen and I can't get it up."
I've seen golf cart batteries mentioned here, and I'm trying to learn more about them. For smaller, DIY, "hybrid" type systems, what are everybody's battery experiences? I'm not interested in investing a lot of money for battery power storage because I have no intention (for now) of leaving the grid, but I would like enough storage for bad weather, dark clouds, and limited emergency backup. My array was self-engineered around the concept of using the power as it's generated (roughly 8 hours per day) and then clocking out and letting the grid handle the rest, so I don't need a really robust battery solution.
