Following is some very general information about solar electric panels. There are many types and applications, but I will cover a few of the most common ones. Small stand alone systems are easy to hook-up, but larger systems that are connected to your home electric wiring should be left to the professionals.

~A solar panel is basically a battery charger. When exposed to sunlight it produces DC current much like a common battery charger that runs off standard household 110 Volt current. The solar charge controller regulates the amount of energy that the panel puts into the battery. Once the battery is fully charged it opens the circuit to prevent damage caused by overcharging. When you use some of the stored energy, it automatically closes the circuit and starts to recharge the battery during sunlight hours. A panel alone can operate DC items directly such as pond pumps without a battery or a controller. In this application the pump would only run during sunlight hours.

~Solar panels are rated in watts. For example a12 volt 15 watt panel averages about 15 watts per hour of sunlight. If you have 8 hours of sun, it will put about 120 watts into a discharged battery in one day.  Multiple panels can be wired together in most cases.  If you wire 3-15 watts panels in parallel (all 3 positive leads wired together and all 3 negative leads wired together) you would get 45 watts per hour. The voltage would remain at 12volts.  If you are trying to charge a battery that is greater than 12 volts you would wire the panels in series.

~Batteries used in solar systems should be deep cycle type. A standard car battery would be damaged quickly by deep discharge cycles. There are two common types of batteries that work well with solar. A sealed lead acid deep cycle is the preferred type.  This type of battery recycles the gases produced during charging. This is a safety feature and you do not have to check the fluid level.  A standard "marine type" also works in well ventilated areas outside of your home. The gases given off during charging are combustible and you will have to monitor the fluid levels on a regular basis. Deep cycle batteries are rated in amp hours; this tells you how much energy the battery can store. For example a 12 volt 35 amp hour battery will store about 420 watts of power.(12Volts X 35ah =420watts). If this battery is completely discharged it would take a 15 watt panel about 35 hours of sunlight to fully charge it. A 45 watt system would do the job in about 12 hours. If you know the wattage of the item you are running, you can determine how long it will run after the sun goes down. A 5 watt DC light bulb would burn for about 84 hours without recharging this battery and a 100 watt laptop would run about 4 hours.

~Inverters are used to convert the 12 volt DC energy in the battery to standard 110 AC voltage that is found in homes in the US. You simply hook the two leads from the battery to the inverter and it will run standard AC items. Inverters are rated in watts and most will have two ratings Continuous Use and Peak.  Peak is what it can handle for a short period of time.  Many items require more energy to start than they do once they are running. As stated above once you know the wattage of the item you are trying to run, you will know what size inverter to use. Most standard household AC items perform well with a standard modified sine inverter. Some sensitive test equipment may require a pure sine inverter that is much more expensive.

~ There are tax incentives available from the federal government and some states. The recent package gives you a 30% tax credit for solar. That means that if you spend $1,000 you could get $300 of it back from the federal government. I am not a tax advisor, so please check with your accountant or search the web for details. Dsireusa.org (Database of state incentives for renewable energy) is a good place to start, but it doesn’t always have the latest changes posted.

~ Over the years I have had many folks tell me "I don’t know anything about solar". I hope this brief overview will take the mystery out of solar electricity. Small stand alone kits can be installed by the average home handyman. While the initial expense is still high compared to electric from the grid, once you are up and running, it should provide years of free energy. Right now it is probably a better place to invest your money than many other available options.

~ There are many ways to use solar energy. RV, boats, cabins, and any remote application is a natural choice where there is no electricity available. If your primary goal is reduce energy use in your home, a combination of conservation and solar is generally required. For example, you may put in a 3 panel 405 watt per hour large system to run a window air conditioner in your bedroom and turn the central air unit off at night. This same system could be used to do the same during the heating season with a small electric space heater. Smaller kits to run a fan would allow you to raise your thermostat a few degrees in the summer.

~ If you live in an area with frequent power outages, solar kits can provide back-up power. With this use in mind, you would probably just use a small panel to keep a large battery pack charged for emergency use. If your outages are the result of advance warning storms, you could also add a few panels to use some energy on a daily basis and then make sure the batteries are fully charged if there is a storm coming.

~With the basic understanding solar, you can generally recharge any battery powered item. In some cases you can charge directly from the battery. Another option is to use the standard AC charger that you already own plugged into an inverter connected to a solar charged battery.

~This is only meant to give you a brief overview of the basics regarding solar panels, controllers, batteries and inverters, and a short list of uses. Most solar kits can be expanded by adding more panels and batteries at a later dat. In most cases I advise folk to start with a small kit and add-on once they become more familiar the benefits of producing and using your own power. –Thanks for your interest in renewable energy.