Charge Controllers

While it may appear to folks passing a house that the home's solar panels are catching all the energy from the sun and then sending it directly into the house's electrical appliances, it just isn't that simple. Once the sunlight has entered the solar panels, it meets up with a solar charge controller, the first of many devices (such as regulators, inverters, and more) that will be busily manipulating, converting and regulating the DC current that the power starts out as. Through the clever use of charge controllers the DC electricity is saved in your batteries, and then, as it is sent out to your appliances, the inverter converts the DC into AC, the kind of electricity used by household appliances.

A charge controller works similarly to the voltage regulator in a car, regulating the voltage that is needed to make the car start and keep it going. Batteries in a solar system work much like your auto's battery, storing energy for when it is needed. Likewise, a battery charge controller protects the system it is connected to by allowing the system's batteries to safely store power and distribute it in appropriate levels. These battery charge controllers are essential, along with the inverters that actually convert the DC power from your battery into the 120 volt AC current that your household appliances use.

Once you understand the basic job that a charge controller does, you'll want to investigate the finer points of the products available to you. Let's look at a few of them. Apollo solar charge controllers are known for their suitability for low-power lighting displays, such as Christmas lights. Morningstar charge controllers are outstanding at charging multiple batteries from a single PV array. ASC's solid state charge regulator is encapsulated in epoxy, making it moisture resistant and ideal for marine and outdoor uses.

The Sunwize charge controller is very small, and is made to fit inside most panel junction boxes or it can attach directly onto a battery. Also, like the ASC model it is waterproof.

The Blue Sky charge controller is designed to be easily setup and installed, and features load control.

Returning to our automotive analogy for a moment brings us to the ICP charge controllers (now available through JC Whitney) that allow you to use the sun to charge your car's battery. And don't feel left out, RV owners; there are RV charge controller kits available just for your needs.

Before we finish up, we should point out that charge controllers are available in many voltage ratings, everything from 12 to 36 volt charge controllers. For higher voltage needs there are even 48, 54, and 60 volt systems.