VERY nice compared to mine. Nice and level with easy grass/weed control. Though I imagine pretty costly with very high labor and material content.
8/1/2020
I think I'll use this post to expand on my love affair with E/W steeply sloping two faced rails. I've had to go over the points several times to different people/groups.
I first started using single face rails, not steeply sloping, with rather random orientations. Mainly pointed away from shading. I've long been aware that almost any pointing direction can give 90+% of total energy as optimal pointing. I had considered N/S rails with E panels on one side and W on the other. I first rejected the idea because of the limited access to the microinverters which hang from the rails. But, finally, I was swayed by the near half cost of mounting. Using used oil well pipe, about $20 worth will support 9-10 panels on one side. OR 18-20 panels on both sides. So, my ground mounts can cost as little as about $1/panel. A negative: since the lower ends of the panels sit on the ground, the strings of panels never look straight due to ground surface variations. I accept that negative as a good cost trade off.
I was further swayed by the need to "flatten my peak". Even though E or W panels produce less energy than S panels, the sum of one E plus one W is considerably more than one S. AND the through the day power curve is significantly flatter. I typically produce more than 80% of the peak for about 9 hours during the summer. If the peak is near the capacity of a transformer (or wiring to the transformer), total energy production capacity is increased with E/W panels. That is, E/W panels maximize the use of the transformer and the wiring between transformer and panels.
In the good old days when Enphase M215s were going for $35 plus $15 for cable, my installed costs were about $110 per 245-250w panel. The M125s disappeared from the market and I was forced to consider string inverters which are much more difficult to install and much more prone to "getting working right" problems. But, the potential is for cost to be as low as about $15/panel. That puts my cost per panel down as low as about $70 even considering the increased wiring cost for strings. Working with string inverters and E/W panels illuminated the possibility of inverters doing "double duty". That is using near the full inverter capacity on two sets of panels. Producing from E panels in the mornings and the same inverter producing from W panels in the afternoons.
A single E or W panel can be expected to produce about 1 kwh on a good day. Under similar conditions, an optimally pointed S panel might produce 1.1-1.2 kwh. Observed average day (over several weeks over about 100 panels) is about .7 kwh/panel/day for string inverters and .85 kwh/panel/day for M215 micro inverters.
I have recently failed to produce similar "double duty" results from micro inverters. That is, having a single micro inverter serving both one E panel and one W. Preliminary results are that SolarBridge inverters work fairly well while M215s work poorly.
My goal is to get a ~5 year payback by selling energy for $.06+ per kwh. It will take a few more years to see if I can achieve that but results are so far very encouraging. My monthly income is approaching $700 and climbing. Investment has been $60k+.
Take away points on my E/W panels mounted on rails on one end and and resting on the ground on the other:
1) energy production is not greatly less than optimally pointed panels
2) mounting costs are minimized, indeed, mounting cost savings are huge
3) use of grid connection is maximized
8/31/2020
Yet another turn around on doing double duty with M215s. More recent experiments indicated that the M215s may do a little BETTER than the SolarBridges. I'm in the process of converting the first of three rails near the RV building from 18E+18W with 36 M215s to 19E+19W with 19 M215s. Preliminary results are that the shared inverter panels are giving about 700 wh/day.
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