Many solar owners do not know what the MPPT charge controller does, or even if they need one. So we wrote this article as the answer to a question we get asked often, which is “do I need a MPPT charge controller?” In the article, we’ll also guide you on how to properly size an MPPT device.
What is MPPT Charge Controller?
MPPT charge controller means a smart type of solar charging device that’s meant to ensure the optimized working of your PV power system. That’s because it continually monitors the array current and voltage outputs, deciding their best combinations at any given time.
The MPPT charge controller will often come included in your system, sometimes even built into the inverter — or it may not. When it isn’t a part of the system, the only option is to purchase one. But what is MPPT in full? You may ask.
MPPT Charge Controller Meaning
MPPT is Maximum Power Point Tracking in full. It means the MPPT device works by tracking the array voltage and current levels and, using the information, finds the point at which the power will be highest, usually based on what’s called the I-V curve.
What Does MPPT Charge Controller Do?
The MPPT charge controller function is to ensure that your system is efficiently charging the batteries; even in the face of adverse conditions such as cloudy weather or dust and overly high temperatures.
It also ensures the system is not losing energy when conditions are favorable, such as would when temperatures are moderately low and the sunlight intense. So are MPPT controllers worth it? Find out next.
Do I Need a MPPT Charge Controller?
You do! As we have seen, this device plays a critical role in ensuring the healthy operation of your PV system. Your storage batteries will charge optimally — even when the array voltage is low —and efficiently when the voltage is high. That being said, you need the MPPT solar charge controller if:
- Your solar system didn’t come with one or the inverter doesn’t have it.
- Your area is prone to unfavorable conditions such as cloud cover or dust.
- You intend to upgrade to a larger system or already own one.
Advantages of MPPT Charge Controller
The MPPT controller offers many benefits, more so if you have several panels installed or if you’re are generating more than 150 watts. The advantages of MPPT solar charge controller include the following:
- Solar panel output efficiency: the MPPT system constantly monitors array output to find the right balance for current and voltage, thus maximizing power.
- Optimized charging of the solar storage devices: MPPT ensures the highest power output to charge your batteries even when there’s reduced array voltage.
- You can use a larger number of panels: since the MPPT charge controller working principle ensures reduced wastage of energy, you can effectively use it with a lager system.
MPPT Charge Controller vs. PWM
PWM here is used to mean the Pulse Width Modulation type of solar charge controller. This device works by limiting the current going to the batteries. However, it has several shortcomings that make the MPPT device a better option. Here’s are some of the advantages of MPPT charge controller over PWM.
- There’s no energy loss when using an MPPT controller, since it manipulates both current and voltage levels, unlike the current-limiting method of the PWM device.
- The MPPT charge controller working allows you to use several panels efficiently, without energy losses, even when the panel output is higher than the rated charging current.
- With the MPPT device, unfavorable weather conditions will not significantly affect your system like when using a PWM controller.
What MPPT Charge Controller Do I Need?
Solar systems are different. Climates, too, where the systems are used or installed. Therefore, it’s important that you find a device the fits your specific system, both in terms of power rating and type.
You may also want to budget for the device beforehand. So here, we take a look at how to size MPPT solar charge controller devices. Also, the amount you’ll likely spend to acquire one.
MPPT Charge Controller Sizing
MPPT solar controller sizing takes into account these factors: the array or solar panel total wattage, the combined voltage of your solar batteries, and your charging needs. Follow these tips when looking for an appropriate type of the device for your system.
- Rate your MPPT device based on one, the battery voltage and two, the input voltage of the array. This will ensure compatibility and safe operation of the charge controller.
- Ensure the MPPT’s current rating for current matches that of your system or in other word, the amount of amps that the controller can output to the battery.
- To find the MPPT rating for output current, it’s recommended to divide the array wattage by the value for battery voltage. As an example, it could be 2000W divided by 24V to give you the appropriate MPPT rating in amperes (A).
MPPT Charge Controller Price
The MPPT charge controller price will, no doubt, vary depending on these factors: the brand, size in terms of current and voltage, efficiency rating, and any additional features. Compared to PWM controllers, MPPT devices generally cost more up front, with amounts ranging from $100 to as high as $600 or more.
Our advice is to ensure that you’re buying your charge controller from a reputable solar manufacturer. Ensure also, that you’re getting a quality product that will allow your PV system to operate not only efficiently but also safely.
To sum up, we should say that the MPPT charge controller is a vital part of any solar system. It ensures the system is extracting the maximum amount of power at any given time, regardless of the varying weather conditions. Because it’s always tracking the array current and voltage levels, you as the PV system owner, are assured of an efficient system and optimal power generation.