Solar energy is well known to people who are interested in living off the grid. In an off-grid solar energy system, a battery and solar panels work together to generate electricity, heat, and cool air when they are needed. A solar charge controller is also important in an off-grid solar energy system.
If you're unfamiliar with solar charge controllers and wondering what they do as well as how they work, then you've come to the right place. In this article, we'll explain what you need to know about solar charge controllers: What they do, how they work and why you might need one.
What Are Solar Charge Controllers and How Do They Work?
Solar charge controllers can be challenging to comprehend, but at their simplest level, they can be thought of as a bridge between the solar panel and the battery. It is possible to encounter dangerous situations when solar panels are able to collect more energy than the attached battery can handle, which can be a sign that they are malfunctioning. The solar charge controller works by "controlling" the flow of electricity from the solar panel to the battery and back, making sure that the power does not exceed the load that the battery can handle, and also preventing the excess energy from being wasted.
This job is carried out by the solar charge controller, which measures the voltage of the battery and calculates how much additional energy the battery can safely handle using constant calculations based on the voltage of the battery.
The battery can also supply energy to the solar panels occasionally, since electricity always flows from a higher voltage to a lower voltage. As a result, if several days of cloudy weather occur in an area and the solar panels don't gather energy, the stored power in the battery could flow to the solar panels and cause damage without a solar charge controller (since the controller only allows electricity to flow one way).
Is a Solar Charge Controller Always Necessary?
Solar charge controllers aren't necessary if your solar energy system is connected to the city grid. The city grid will store any excess energy, so you don't need one. It is important to use a solar charge controller on all off-grid systems, even small ones, if you want to extend the life of your solar panels and batteries.
Types of Solar Charge Controllers
There are two main types of solar charge controllers: those with pulse-width modulation, and those with maximum power point tracking or MPPT. PWM stands for pulse-width modulation, while MPPT stands for maximum power point tracking. Below, you will find a brief description of the features and functionality of each solar charge controller type:
- PWM charge controllers:A PWM charge controller is best suited to systems with a small number of solar panels and a small amount of battery storage (think: powering an RV). PWM charge controllers are less expensive than MPPT charge controllers and are less efficient than MPPT charge controllers.
- MPPT charge controllers: Compared to PWM charge controllers, these controllers are slightly more expensive, but are best suited for larger off-grid systems.
How Much Do Solar Charge Controllers Cost?
It is estimated that MPPT solar charge controllers cost between $70 and $600, which may depend on the type of controller that you choose. At the high end, you may be able to find a larger controller that can handle higher voltages, while at the other end, you may find a less powerful MPPT solar charge controller.
Compared to MPPT solar charge controllers, PWM controllers tend to be less expensive, ranging from $15 to $40. However, this lower price reflects the limited capabilities that PWM controllers have as compared to MPPT solar charge controllers. When you're wondering which is the best option for your solar energy system, you should err on the side of caution, especially if you plan to expand or expand the size of your system in the future.
Key Features of a Solar Charge Controller
There are several key features of a solar charge controller that can help you better understand how they work.
- Flow of power:In solar systems, a solar charge controller regulates the flow of power between the solar panel and the backup battery, preventing the battery from being overloaded, which can drastically shorten its life.
- Battery choice: You can select the type of battery that will be connected to either type of solar charge controller, PWM or MPPT.
- Range of voltages: The voltage range that you can set on both types of solar charge controllers varies depending on the type and size of the controller.
- Display: There are solar charge controllers with LCD displays and others that use dials for setting voltages and other settings.
- Heat sensor:The temperature of batteries can be monitored by a heat sensor on some solar charge controllers.
- Smart options:Charge controllers with Bluetooth connectivity and apps are also available.
Is Solar Charge Controller Worth It?
If you have a solar energy system that isn't connected to a city grid, a solar charge controller isn't just worth it: it's a critical component that you shouldn't miss. Due to the solar charge controller, excess voltage won't flow into your backup battery, extending its life. Rather than regulating energy, it converts it into electrical pulses that the battery can handle better.
Additionally, the solar charge controller prevents power from backflowing from the battery to the solar panels, which can damage them as well.