Solar Charge Controllers

If a solar power system uses batteries, it will also require a solar charge controller. They work to regulate the power moving from the solar panels to the batteries. When overcharged, the life of a battery is reduced, and a proper charge controller will make sure that this doesn’t happen.

When the level of voltage in a battery passes a certain threshold, the charge controller will halt the charging process. In older charge controllers, this was accomplished with the use of a mechanical relay. Even an installation with DIY Solar Panels needs a solar charge controller.

More recent charge controllers use pulse width modulation (PWM). This is a process in which, as the battery gets closer to being fully charged, the amount of power being transferred to it gradually decreases. In addition to decreasing the stress on the batteries caused by the charging process, PWM keeps them more fully charged, making them more efficient from the user’s perspective. It can also keep batteries in a fully|completely|100%] charged state, or “floating,” indefinitely. As they don’t rely on mechanical connections, PWM chargers also tend to be more reliable.

Maximum power point tracking, or MPPT, is the most recent advancement in solar charge controller technology. MPPT controllers have the ability to turn excess voltage into amperage. This feature has a couple of significant benefits.

Most solar power systems use 12 volt batteries, not unlike the ones found in cars, but these features work regardless of voltage. Most solar panels provide more voltage than is needed by the batteries. When the extra voltage is turned into amps, the charge voltage remains at an optimal level, while the time it takes to fully charge the batteries is reduced. This way, the solar power system as a whole maintains the highest possible level of efficiency.

Power loss is also largely eliminated with MPPT charge controllers. The lower the voltage of electricity, the more loss it experiences as it travels along wires. The power used by a PWM charge controller used with 12v batteries is usually around 18v. An MPPT controller will use the highest voltage of any type of charge controller currently available. MPPT controllers have less power loss because of this improvement. Homemade Solar Panels are a awesome way to save money.

MPPT charge controllers are usually more expensive than older ones, but the upgrade is significant. They’re highly recommended because of this.

Modern solar charge controllers also have the ability to prevent reverse-current flow. Solar panels will stop generating electricity when they are no longer in contact with sunlight, and the batteries may actually start sending electricity back to them at these times. This is another obstacle in terms of the overall efficiency of a solar power system. At these times, a charge controller will open the circuit, preventing any power from being transferred back to the solar panels.