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Bringing some of the benefits of electrical power to our off-grid home has been a hit-or-miss affair. Over the years we’ve tried some very simple approaches to lighting and small battery recharging for our flashlights, such as hauling a 12 volt car battery to a small rural school about a half mile away every time it needed to be topped up. This was time consuming and inefficient.

But we didn’t want to lose the feel of our simple home by bringing in a large generator and the jugs of gas needed to run it, and the prospect of setting up a wind turbine or solar array seemed expensive and a technological eyesore in a natural setting.

Editor’s Note: This article was first posted in 2012. Since then we’ve made a few upgrades to our system that are reflected in this updated version. Basically, we’ve added a couple panels and got a larger capacity charge controller, and added a battery charger to supplement the system during the darkest weeks of winter when solar power is at a minimum.

For many years we managed to get along without the conveniences which electricity can provide, but developing Eartheasy.com using a dialup internet connection on a phone line strung through the woods was challenging, and charging my laptop became a regular necessity. A few years ago, wireless broadband was introduced to our area, and the promise of high-speed internet was the stimulus we needed to build our own reliable, affordable and simple “do-it-yourself” alternative energy system.

…developing Eartheasy.com using a dialup internet connection on a phone line strung through the woods was challenging…

Today, with the help of a local expert on off grid home solar power and alternative energy systems, we have the best of both worlds. Our basic solar powered energy system provides more electricity than we expected, it has been very reliable and maintenance-free, and it is almost entirely hidden from view. A solar panel on the roof with a few wires leading to a small battery bank powers my laptop, and a radio mounted on a tree for receiving the wireless broadband signal. The system also provides enough energy to charge several small power tools, run our home sound system and, amazingly, power a full-size chest refrigerator year round.

The cost of this complete solar system, in today’s pricing for the components, was about $1200.

Our simple home solar power system is comprised of four basic components: the solar panels, a charge controller, two 6-volt golf cart batteries and a small inverter. My son and I were able to install the system in a few hours, and there have been no maintenance issues other than checking the fluid level in the batteries every few months and cleaning the panel surfaces once in a while. Also every year or two I lift up one side of each panel to sweep out any leaves or pine needles that may have collected there.

The cost of this complete solar system, in today’s pricing for the components, was about $1200. It should be noted that I bought the panels ‘used’ for $100 each. Many folks in our community have replaced their 123-watt panels with newer 250-watt ones, which cost about $250 each. So the 123’s were readily available and I was satisfied with the amount of energy they would provide.

The four components are the batteries, charge controller (bottom right), inverter (top right) and battery charger (below inverter).

The four components are the batteries, charge controller (bottom right), inverter (top right) and battery charger (below inverter).

The basic components of this off grid solar power system are as follows:

1. Solar panels

We have three solar panels mounted on the roof of our home: 123 watt Sharp Photovoltaic Modules, model 123UJF. The panels are equipped with permanently attached junction boxes for ease of installation of wires and conduit. For each panel, two boards are lag screwed into the roof and the solar panel is bolted to the boards using wing nuts, so it’s easy to lift if maintenance is required. The panel surfaces are about 5” above the roof surface. Two wires run from the solar panels, one is the power line and the other is a ground line. The power line runs down the roof to the charge controller, where there is a fuse. A box on the porch houses the charge controller, inverter and batteries. The ground wire runs beneath the house and is attached to a steel rod that is driven about two feet into the earth.

Panel on roof/panel specs from back of panel

Panel on roof/panel specs from back of panel

It should be noted that the panel guidelines state that the installation of PV modules requires a “great degree of skill and should only be performed by qualified licensed professionals, including licensed contractors and licensed electricians.” We installed our system ourselves because our supplier, who is a licensed installer, gave us explicit directions and came by to inspect the installation after it was done. We suggest that you follow the recommendation as stated in the module instructions with regard to installation.


The cost of the solar panels in today’s pricing is about $1 per watt.

2. Charge Controller

We use a Morningstar ProStar30 Charge Controller that automatically adjusts the amount of power running into the battery. The controller has a small LED light which indicates the state of charge so it’s easy to see when the batteries are fully charged or if they are becoming depleted. The light flashes green, amber or red, indicating the battery status at any given time. A digital readout shows the battery voltage level and the rate of charge coming from the panels. A quick glance at the charge controller lets us know if we have sufficient power or if we need to cut back a bit on our electricity use until the batteries are topped up again.

Charge Controller

Charge Controller

The cost of the Morningstar ProStar30 Charge Controller was about $250. You can get it for around $200 today.

3. Battery Bank

Two 6-volt golf cart batteries are wired in series for a 12 volt system. Each battery is rated at 232 amp hours. The batteries are enclosed in a wooden chest with hinged lid, and the top panel of the chest is removed to provide plenty of ventilation. The battery posts and connections are kept clean, and periodically checked to ensure good connections.

The two batteries/closeup of label

The two batteries/closeup of label


The ventilated battery box on porch

The four components are installed in this cedar box with ventilation slot. This box doubles a bench to sit on while removing shoes.

The cost for the two batteries was about $400.

4. Inverter

The final piece of the system is a small inverter which converts the 12 volt DC power into 120 volt AC power. This enables us to use standard electric devices without the need for adaptors. Inverters are available in a wide range of wattages for different size systems. Ours is a small inverter made by Nexxtech, rated at 300 watts, with a 500 watt surge capacity. It comes with two cables, red and black, with alligator clip ends for gripping to the battery posts. In choosing which size inverter to buy, we calculated how much power was available to our system and what devices we wanted to run. In calculating power needs, it is important to add the power requirements when two or more devices are running simultaneously.

Inverter

This is our small Nexxtech inverter.

Our Nexxtech 300 watt inverter cost about $30.

Backup (optional)

This past year we added a battery charger to the system that serves as supplemental power. Running the battery charger when the batteries get low enables us to have more light and power in the darkest days of winter. The charger is in the same box with the batteries and other components. You may see in the pictures there are two extension cords coming up through the floor – these lead to our woodshed where we have a small Honda 2000 generator. To run the charger, we start the generator, plug the charger into one of the extension cords, and also plug the inverter power line into the other extension cord. The generator only needs to run for about 30 minutes to bring the batteries back up to 12.8 or higher. Then the generator is shut off, the battery charger unplugged, and the inverter power line plugged back in. This process takes only a minute or two, and the restored batteries have sufficient power till the rooftop panels start to get light the next day.

battery charger

left: Battery charger is on floor beneath inverter. right. Close-up of battery charger.

What this system provides:

An alternative energy system can be used to provide electric power to any number of electric devices, such as appliances, tools and computers. The bigger the system, obviously, the more power it will provide. To give you an idea of the capacity of a small system like ours, here is what we use our solar energy system to power:

DC Refrigerator

Refrigeration: This is a DC powered refrigerator, the same size as a conventional chest freezer (4’ wide). The refrigerator draws 40 watts of power and can be converted to a freezer by replacing the thermostat. Since the refrigerator is a DC model, it is wired directly to the battery, bypassing the inverter. So the refrigerator keeps running even if the inverter is turned off. Our refrigerator has been running continuously for over 8 years without any problems. Even during the dark days of winter, the solar panels provide adequate power to keep it running.

Music: Our home has a Vers sound system which lets us use an iPod or direct cable from an iPhone or computer to deliver a rich sound while drawing relatively little power. We can run this sound system about 3 hours a day in winter, and as much as we want in summer.

Light above table

Light: The big change for our home is electric lights. We have replaced our kerosene lights with a few of these LED lights, which are only 7 watts each.

Internet: Our solar system also provides adequate power to run a laptop computer, a tablet and to recharge cell phones. It also powers a router from so that multiple computers can be operated ‘wifi’ at the same time. In addition to the router, a small radio is installed on a tree about 300’ from our house which receives the wireless broadband and transmits the signal to the house.

Laptop/rechargeable screwdriver

Small tools and appliances: The system also recharges small tools, such as a battery-powered driver-drill. Our system recharges the battery for this tool in about 30 minutes.

These are the principle applications we use which are provided by the solar power system described above. However, you can use a wide variety of electric devices as needed. Today, we enjoy the benefits of our system without feeling a technological intrusion into our off-grid homestead and lifestyle. The refrigerator especially has made a big improvement in our day to day living, since storing food is so much easier. And we don’t miss the kerosene lamps.

Bringing electricity to rural locations is something of a balancing act since we don’t want our simple lifestyle changed by too many electrical gadgets. It does require some restraint to keep things simple, but the few electric amenities we now have are most appreciated!

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