The first thing to remember is that solar is not cheap! The power is free and sustainable, but it’s costly to get there. A person can spend as much money as you want, in that direction. I did not go whole hog on my system, as I wanted primarily the ability to power a few appliances, and mainly a power source to recharge my rechargeable batteries.
I have a couple of systems setup in different locations, as well as the ability to setup portable arrays. My main array consists of:
- 4 – 85 watt panels & a 30 watt panel.
- These run to a 21 amp ICP charge regulator/controller, and then to a bank of 8 – 12v deep cycle marine batteries.
- Tied to that I have a 2,000 watt power inverter for the 110 household current, as well as 2 – 12v cigarette lighter type sockets to have the ability to run 12v appliances if needed.
I have a problem with this system in that I really hate to cut trees as you can’t really replace them in your lifetime. So my system doesn’t get full sun all of the day. It gets about 2 thirds of what it could get, but meets my anticipated needs. It will power a small freezer, or a portable ice maker, a 110v chain saw, and many other like items.
I have a secondary array at a nearby building that is not used much to full potential, but is kind of a backup system.
It consists of:
- 1- 85 watt panel, and
- 2 – 50 watt folding panels that run to another charge regulator/controller and
- only 2 – 12v deep cycle batteries.
- This then runs to another 2,000 watt inverter that is actually a backup in case of a failure of my primary unit.
The panels on this array can be plugged into the main array by the use of polarized two way plugs, making it very modular for increasing power to the main system.
At my pond I have a shelter house on which I mounted:
- a 30 watt solar panel that runs to
- a smaller charge regulator/controller and then only
- 1 – 12v deep cycle battery
- This runs out to 12v lights in the ceiling of the shelter house, as well as a couple of cigarette lighter 12v outlets.
I can plug in a 400 watt inverter to the 12v system and power most small appliances that I might have there.
Last, but not least, I have several smaller panel setups that are extremely portable & powerful that can provide 12v power just about anywhere that has sun exposure.
Here are the basic components that you need to set up your solar photovoltaic system:
1. Solar Panels
First you have the solar panel. This is what generates electricity from the sunlight or even artificial light. They come in many sizes, types, prices, and wattages. Power coming from the cell to charge a battery must have a diode in the circuit to keep from discharging the battery when there is no power coming from the solar panel, as the current will flow backwards discharging the battery.
Think of it as a one way valve. Some panels, like the Volkswagen units, have the diode built in. Other wise it is built into the charge regulator/controller if your system is going to use one.
2. Charge Controllers
Second, if you are putting together a larger array of permanently mounted panels, you’ll need a charge regulator/controller to control the charge rate from the solar panels so than you don’t over cook your batteries. These also come in various sizes, types, and prices.
The key thing to remember is that the wattage here must be larger that the total of the wattage of your panels. I made the mistake several times of thinking my system was only going to be a certain size, and later having to buy a larger controller because I was expanding my system. So buy big in the beginning, and you won’t have to buy again later.
Third, the batteries. The best batteries to use are the deep cycle batteries that are commonly used in golf carts. But they are very pricey, heavy, and not easy to find in some places. They usually have to be special ordered in the rural areas like where I live. So I opted for the biggest Marine type deep cycle batteries. Though not cheap either by any means, you get what you pay for.
You now have a system that produces and stores 12v power. There are two things you can do with it in this form. You can hook up an inverter to change the power to 110 volts, or you can use it as it is at 12 volts.
If using an inverter, here are some things to consider. They come in various sizes, types, and of course, prices. In the most common types, there is pure Sine wave and modified Sine wave.
Pure Sine wave is more expensive, but modified Sine wave is fine for most normal use. If you want a technical explanation of what it is, you can Google it. But simply put, some sensitive electronics require pure Sine wave, whereas most will work fine on modified Sine wave.
The inverters are rated by wattage that will show two different numbers. One number is the normal usage wattage, and the other is the surge wattage. Some appliances use a bit more power as they start, but level out at a lower wattage as they run. This is what the surge rating is about.
It is important to understand how much wattage you’ll need to run the appliance you want to use. There is a plug in device called a ‘Kill A Watt’ that runs about $30 that will tell you how much electricity your appliance uses by plugging it in, and then plugging your appliance into it. It can be an eye opener in some cases!
Almost all inverters have overload protection, and low voltage protection. They will auto shut off (sometimes with a small alarm), when over or under loaded.
Buying a quality name brand here is important. I got stung a couple of times with cheap off brand units that were rated higher than they actually worked at. You usually get what you pay for here as well.
What Size Solar Array Do You Need?
I started out very small and worked up. There are those that power a whole house with their setup, but that is very expensive and complicated. Plus the upkeep isn’t very cheap. A smaller system will serve most emergency needs.
I have noticed the Amish in my area use solar power to run their cash registers at their small stores in the area. They also have little outside phone buildings that have solar power to charge the batteries for the fiber optics used in the phone lines. These are all single small solar panels.
Is Solar Power Worth It To You?
As I mentioned in the beginning, this stuff isn’t cheap. It was done over a long period of time so it became more affordable. I started very small with a couple of the Volkswagen solar cells, a plastic battery box that had a built in 12v lighter socket and external terminals, and of course a deep cycle battery, added to that a splitter that allowed multiple lighter sockets for plugging in panels or for power out.
I will post in the future some Do’s and Dont’s as well as some tips for use. There is much to know about solar, but it isn’t as complicated as most might think, for the smaller setups like mine.