Auxilliary electrodes for array grounding

[ggunn]

A that was my point if the scale house has even min. loads you would think it would be close enough to the solar to benefit from the solar power.

Benefit how? Distance has nothing to do with it; whether solar would lower the electric bills for these buildings is solely dependent on where the energy is metered. Once kWh's are on the grid it doesn't matter where they come from. They are all the same.

 

[GoldDigger]

Apples and oranges. Different AHJ's have different policies regarding PV production vs. consumption on residential systems and others regarding commercial systems, but a ground mounted PV system on a landfill is most likely to be a utility scale system. In those systems consumption isn't a significant part of the picture. They exist for the sole purpose of selling energy to the utility.

Unless they are colocated with something high power like a waste treatment plant. That is not uncommon.

 

[ggunn]

Unless they are colocated with something high power like a waste treatment plant. That is not uncommon.

I've done one of those, but the interconnection point was outside the meter. The consumption by the wastewater plant was not an issue. I guess it could be, though.

 

[SolarPro]

Most landfill need to be closed for several years before you can put a system on them. This is do to settling of the site. We do work at several landfills and they do have surveyors come in and use a GPS to check the settling.

Got it. That makes sense. I was wondering how that worked.

 

[beanland]

Horizontal Electrode

Horizontal Electrode

The NEC allows grounding electrodes to be horizontal, you do not have to drive a vertical rod. You can also lay a ground wire horizontally. Power substation ground grids are almost entirely 2/0 and 4/0 copper wire buried 12-24". There has to be some capping soil above the sealing layer in the landfill, as long as you do not penetrate the cap, the sewer gas cannot escape.

 

[ggunn]

The NEC allows grounding electrodes to be horizontal, you do not have to drive a vertical rod. You can also lay a ground wire horizontally. Power substation ground grids are almost entirely 2/0 and 4/0 copper wire buried 12-24". There has to be some capping soil above the sealing layer in the landfill, as long as you do not penetrate the cap, the sewer gas cannot escape.

Don't those grounding methods assume continuity with the Earth (the planet)? Is the cap electrically conductive? It seems to me that a buried plate or wire or horizontal rod might only have continuity with the thin sheet of soil atop the cap.

 

[Smart $]

Don't those grounding methods assume continuity with the Earth (the planet)? Is the cap electrically conductive? It seems to me that a buried plate or wire or horizontal rod might only have continuity with the thin sheet of soil atop the cap.

Within the capped area, you are correct. Installed-horizontal electrodes are not only required to be buried 30", but below permanent moisture level [250.53(A)(1)]. Many overlook this requirement when looking for ways around installing vertical electrodes.

FWIW, Code does not specifically define "soil" and "earth" and relative location to Earth major. :slaphead: