Sunday, July 14, 2013

On Grid, Off Grid Project Results

Solar PowerHouse. the modules in the background are gridtied and some can be switched to DC
Battery wiring is a temporary set up to be upgraded
Back on June 20th, I posted about a fairly simple yet sophisticated solar battery system. I finally got the last of the wiring done last week. In the top picture is the "PowerHouse" which I designed and had local Mennonites make as a prototype two years ago. The idea was to build finished solar systems either gridtied or offgrid battery. The slope of the roof is 38 degrees which is the latitude of southern West Virginia. It fits 6) 230 watt modules, although today you can get 250 watters at less price.
The next picture is inside the PowerHouse showing the batteries, charge controller, combiner and inverter. For a full description and a link for the schematic drawing go to my June 20th post "Sensible Solar Battery System".
Two of the three series relays. Note Enphase microinverter behind timber

On July 5th I posted a schematic of a method of switching gridtied modules to DC so additional power can be collected for the battery system. I was a bit concerned the points in the relays might get damaged by under-load switching. I saw no visible arcing switching back and forth, so I suppose it will work for a long time.
The relay and it's socket are under the middle of the PV module and well protected, None the less, I used silicon dielectric grease on the wires, blade slots, and around the base edge of the relay since it didn't look like it was hermetically sealed. Then on top of that, I sprayed an anti-corrosive into the wire sockets and clamp screws. Ought to last for a while. Please note: I used "touch safe" sockets for added safety.
Basically, I doubled my collection power from 1380 watts to 2760 watts. Theoretically, I could charge the battery pack in 4 sunny hours. So yea, now I'm thinking of another set of 4) 220 A/hr batteries for winter conditions. Cha Ching..but that's the nature of the beast and human nature.

Close up of DPDT relay, socket and wiring

1 comment:

  1. Within a day or two of completion of this project, the grid went down for several hours. I was out walking the dog and when I returned Bob was beaming and enjoying his off grid electricity.

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