by Jeff Shaw
The photos below show my first homepower setup. It will run about 4 rooms in the house.
This first photo shows the 4 Solerex MSX-120 solar panels. At full sun they put out 480 watts, or about 28 amps at 12V DC. The pictures don't do the color of the panels justice, they look like the background of this web page. The panels are wired together at their junction boxes and then joined in the splice box at the bottom of the photo. The DC wiring runs in conduit down the roof and into the equipment closet.
The photo below shows the panels close-up. The panels are directly above the equipment closet and mounted on aluminum channel. By luck, the roof angle is 40 degrees and facing south (perfect)! If you haven't seen these panels before, they are each about the size of a card table.
This shows the equipment closet with its doors closed. The closet was built outside under the carport and has 2x12 shelves, louvered doors, and vent grilles on the sides. The pipe on the left is the engine exhaust from the generator and the vent duct is the blower exhaust. Fresh air intake vents are on the right side (not shown). As you can see, the system is very inconspicuous.
This is a picture of the closet with the doors open. A Trace C40 charge controller (small white box) accepts the current from the roof panels. The controller sends the DC electricity through a Trace DC175 breaker panel (large white box) to protect everything. From there the charge controller monitors the 16 Trojan T105 batteries (maroon) and adjusts the amount of current charging them optimally. If the batteries do not need all of the power being generated by the panels, the charge is stepped back. The Heart Interface 2kw power inverter (top shelf left) converts the battery current (at 12 vdc) to 120vac and then to the house. Below the bottom battery shelf is an Onan 4kw gas powered generator (not shown).
In order to run normal household circuits, the DC power from the batteries or solar panels must be converted to 120V AC power. The next photo shows the Heart inverter and wiring. The blue flex conduits on the right contain 2/0 size interconnects which are fed from the master breaker. The flex at the bottom left is the inverted 120V AC power outlet to the house. The bottom right is auxillary 120V input AC from the generator in case the batteries run low or the sun is not out for an extended period.
The system performance is monitored indoors with a Trimetric power monitor. It monitors charging as well as consumption.