Solar charge controllers have the job of charging batteries correctly. Also known as solar charge regulators, they make sure the right amount of electricity goes to batteries. As such, their role is similar to the chargers we use on smartphones. But their job is a bit more complex. Because whereas utilities put out a steady voltage, the sun does not always shine as bright.
The Regulatory Job of Solar Charge Controllers
Most solar panels in use in homes are rated 16 to 20 volts. Whereas solar batteries are a nominal 12.7 if holding a full charge. Now, if we rated solar charge controllers similarly, they would only provide what batteries needed on cool sunny days.
Therefore, we design solar panels with variable outputs. And then we insert a solar charge regulator in the circuit to moderate the power to what the solar battery wants.
Controlling the Variable Power of the Sun
We need a steady flow of electricity from solar batteries but the sun is fickle. On hazy days, or when the sun is low in the sky, its power drops. Conversely, solar panels are also less efficient when it is blisteringly hot outside. But no worries. Solar charge controllers vary the input between approximately 10.5 and 14.6 volts according to the state of battery charge.
Solar Charge Controllers for Different Applications
Some simple systems do not need a solar charge controller at all. For example, you may not require one to help trickle charge a golf cart battery. But you will definitely need one for your home solar system because the battery is connected in-line.
There are a variety of different types of solar charge controllers on the market. These range from dumb devices to sophisticated digital battery equalizers and monitors. Please play safe. Always consult a qualified electrician before attempting to install solar power.
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Preview Image: Solar Controller Interface
