Solar Power Information: Charge Controllers

Charge controllers are an essential component of stand alone and battery-backup solar home electricity systems. This device serves to level out the direct current produced by the solar panel array that is fed to the batteries backing up your household electricity.

Modern charge controllers are able to regulate the amount of power supplied to batteries according to the charge level of those batteries. This alleviates problems caused by too much electricity flowing into the battery cells when charging. This can cause corrosion of the internal electrodes of the battery cells, which results in lower maximum charge levels for the battery and also a shorter battery life.

Early charge controllers were simple on / off mechanisms that would charge the battery array at full power regardless of the level of charge those batteries held. By comparison, modern regulators reduce or increase the current as needed to best serve the batteries. This process is called Pulse Width Modulation, or PWM.

As with all home solar electricity components, the range of products available is large with a quality range to match. While it is not necessary to know the technical specifics of PWM, it is an important factor to consider when looking at system component options. Fortunately, the majority of charge controllers on the market today incorporate PWM, though there are varying degrees of finesse that they do this with.

As with the sine wave inverters used to adapt solar Direct Current to Alternating Current, having accurate solar power information and investing in a good charge controller will save you lots of money and headaches in the long run. A few dollars saved on a cheap controller will be quickly forfeited if you need to replace all your lead-acid batteries well before their expected expiry date. Lead acid batteries for solar installations can cost anywhere up to $2000au for a full set, so ensuring that they have the longest possible lifespan is clearly the sensible thing to do.