Total (plus shipping & handling) $27,595

Total (plus shipping & handling) $27,595

My Safety Systems

I have fire extinguishers for electrical fires at all doors to the garage, which is where this Frankenstein laboratory is. Other safety equipment includes baking soda, bottles of distilled water, eye goggles, first aid kits, and a smoke alarm.

A 12 volt, low wattage fan sucks air through a 1-1/2 inch (38 mm) duct from the two battery banks, which are in separate boxes insulated with two layers of R-19 fiberglass insulation. All connections are coated with a battery corrosion preventative spray. In addition, each cell has a Hydrocap.

Each positive inverter cable has a Class T fuse located in the battery box for overcurrent protection. Then #2/0 (67 mm2) and #4 (21 mm2) wire exits to cable quick-disconnects, bolted disconnect switches, and other fuse systems. There is a common ground bus bar, and all equipment grounds are terminated at that bus. The bus is in turn connected to buried ground rods. The battery negatives are also common; only the positives of each battery bank are isolated.

Lightning arrestors are installed in the PV output circuits before they go to their charge controllers, and each panel is individually fused. All AC systems, of which there are four, have lightning protection as well.

Measurements & Code

One of the measurements I'm really interested in is how many DC watt-hours the PVs are producing. So I

From three panels to twenty-five—the system keeps growing, and growing and growing! The sixteen KY120, seven KY80 and two SP75 PV panels.

the combiner block. From there the combined juice goes to a C40, and then to a switch and to the Trojan batteries.

The next subarray is 720 watts— three Kyocera 80 watt panels and four Kyocera 120 watt panels, controlled by a Trace C60. These two PV systems go to a bank of eighteen Trojan T-105 batteries with Hydrocaps. Covering the batteries are sheets of Plexiglas, so that if I drop a wrench on them, there is no nuclear meltdown.

This battery bank powers the Trace DR1512 modified square wave inverter and the PROsine 1,000 watt true sine wave inverter. Each inverter powers a separate breaker box.

decided to purchase Trace's digital AH displays for each charge controller. At 8 AM every Sunday, I log the amp-hours each of the four subarrays has produced. Multiplying the total AH figure by 12.5 volts gives me the estimated collected watt-hours for the past week.

I also have a Trace TM500 amp-hour meter for monitoring the Trojan battery bank, and a Bogart TriMetric 2020 amp-hour meter for monitoring the Rolls bank. These meters compare incoming amp-hours from the PVs to amp-hours being consumed by the loads. Amp-hour meters are the most accurate and convenient way to keep track of the state of charge (SOC) of each battery bank.

Well, this is purely an experimental, evolving system. Having said that, some things are not code compliant. The positives coming in from the panels are not in conduit. And they are white wire with red tape, and black is negative. Having held two country's amateur radio licenses for forty years, I am used to that wiring convention.

For the most part, this system is code compliant, if not pretty. While it runs itself, if I ever sell the house, there will be a lot of training.

System Details

Beginning at the far east end of the garage is my 320 watt system of four Kyocera 80 watt panels. The panels are fused individually. PV output is routed through DC rated automotive fuses and then paralleled up at a combiner block. A lightning arrestor is also installed at

The next system, continuing west along the garage is the Rolls 4KS21PS battery bank, its PV array, and its inverters. These batteries use two C60 controllers, and two subarrays. One is for six Kyocera 120 watt panels, the other has six of the same panels as well as two Siemens SP75 panels. These collect a rated 720 watts and 870 watts, respectively. The ratios of PV output and the battery amp-hour capacities of the systems match the daily inverter usage.

Inconspicuous PVs

And where are the panels? They are on the garage roof at a roof pitch of 20 degrees. This is not efficient, but I wanted the system to be pleasing to the eye. The panels were not a significant roof load. But where the bolts didn't meet solid wood beams, I attached braces to reduce wind lifting problems.

Just in case of another sort of "lifting" problem, I added an alarm system to protect the solar panels from sprouting wings. I have a continuous loop of stranded insulated wire going through at least one unused mounting hole in each panel. That closed loop goes to the normally-closed input of an old Radio Shack alarm controller, powered by the Rolls batteries.

I used the roof angle of 20 degrees for the PV arrays. Afterwards, a friend asked me if I would have sun in the winter, given the fact that the house is south of my garage roof, which has the PV arrays, and the fact that there are three large trees. My heart sank—actually stopped would be a better description.

With my solar powered computer, I went to, which gave me azimuth and

Wheaton-Smith Critical Loads


Phantom Watts

Normal Watts

Peak Watts

KWH per Day

Sears fridge

Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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