Not sure where this will lead.
I started considering solar due to a combination of things: a buddy getting a system installed, learning the difference between leased and owned systems, and being really annoyed with those green-shirted sales people in Home Depot pushing PV systems. At the time I figured (correctly I think) that the reason they push so hard is because it's a great business plan for them, and whatever's good for them is bad for us.
Anyway, after getting a quote from a family-owned installation company, I couldn't help but wonder "how hard could it be?" Looks like a DIY system would be about 50% that of an installed system; between that and the 30% tax write-off, it makes it fairly affordable. What really muddies the water though is the constantly changing rules made by electric companies. Here in the San Diego area, Time-Of-Use (TOU) is getting implemented and challenges solar's advantages, or at least, reduces them. Roughly a year from now, electric rates will be adjusted much higher between 4-9 pm during the summer, which really limit's solar's ability to chip away at that high cost due to hitting so late in the day.
One reason I started a thread here was to make people think about how much we're paying for each and every powered filter component. For example, I'm running:
1. A 1/4-hp W. Lim pump (371W) as a main pump.
2. A 120W UV
3. A 1/15-hp W. Lim pump (160W) driving the skimmer and SG filters
4. Two air pumps, around 120W for both
Given the big rate hike during the late afternoon I wondered what I could do from a conservation point of view, with or without solar. Due to the filter's configuration, the main pump and UV could be put on a timer, shutting off both between 4-9pm. The skimmer, SG filters, and aeration would be left on, ensuring clean water and good oxygenation of the moving-bed filter and pond.
The saved money works out as:
371W + 120W = ~500W = 0.5KWh
0.5KWh * 5hrs * 30 days = 75KWh
75KWh * $0.42 = $31 per month
The point is that by reviewing your setup, there may be ways to lower your bill yet retain a healthy pond.
More later.