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Letter Re: Generating Photovoltaic Power When Grid Power is Available
Jim:
I agree completely with your comment that [photovoltaic] solar systems should
not be grid-tied to run the meter backward [to isolate the photovoltaic system
from potentially devastating coupled electromagnetic pulse (EMP).]
When the grid is available to home or retreat, I believe it is worth connecting.
It is the easiest way to deal with barns, 220 volt tools and wells, but some
thought to solar wiring can go a long way. Many custom homes and retreats were
built with home-run wiring before the price of wire jumped so high. A number
of these homes and retreats can be solar-controlled simply by DPDT switching
circuit wiring at the fuse box.
Think of two modes – solar when the grid is up and solar when the grid
is down. The thing many people have not thought through is how to utilize their
solar power when the grid is up and they make the lazy choice to grid-tie to
realize the value from their solar system. Grid-up, I run a server and a large
desktop computer from solar. Grid-down, I only run my laptop and have to control
my well (dual 110 volt inverters) versus my refrigerator and chest freezer
so they do not run at the same time. Grid-up, all my barns, refrigeration and
220 VAC is
on the grid and most other 110 VAC is off-grid. When I leave the property,
the grid tie is broken (I don’t need the well then.) and all phantom
loads, lighting and refrigeration are solar run.
All my computers are hooked to my computer network by wireless cards. My television
is wireless as well. This was very difficult to do because I have Charter [Communications,
Inc.] high-definition cable [television service.] It took a broad-band wireless
repeater between the converter box and the television. My solar system utilizes
all available solar power and protects me fairly well from EMP. My home/retreat
has well-insulated metal siding and metal roof for some added fire and EMP
protection. - SAR
