Solar Charge Controllers Limiting Your Losses

Posted on 09/22/2017 at 12:00 by Seth Hansen

Charge Controllers Limiting Your Losses Title Graphic

Nobody likes a dead battery.


You want power available to charge your device. 


To keep your fleet of vehicles online.


To stay safe during inclement weather.


To get things done. 


Often you might think about inexpensive batteries versus their elite counterpart, but often we neglect the importance of a charge controller in the solar collection process. 


If paired with an inappropriate or inefficient controller, you can throw away enormous amounts of energy. 


To discern the best controller for your situation, let's talk through the options, their advantages and disadvantages so you can make the most informed decision. 


At its most basic level, a charge controller maintains your battery's health and ensures that you aren't damaging it. This is achieved by regulating the amount of voltage and can be achieved in a few different ways. 


There are many different styles of charge controllers on the market, but at the most basic level, there are three types. Those that use Pulse Wave Modulation (PWM), Maximum Power Point Tracking (MPPT) and Ratio Power Point Tracking.


Types of Solar Charge Controllers


Pulse Width Modulation (PWM)

PWM controllers are an older genre that will only buck or drop the voltage to the appropriate number for your specific battery. The controller reads the voltage appropriate for your battery and pulls it down to that number. As we will discuss, these controllers can work in some scenarios but prove troublesome in others. 


Maximum Power Point Tracking (MPPT)

MPPT controllers are a more modern take on controllers that can optimize the amount of power going into the battery, meaning faster charging times and less waste. This is accomplished by the controller checking the voltage incrementally until it finds the point where it can collect the most power. 


Ratio Power Point Tracking

Ratio Power Point Tracking controllers function similarly to MPPT controllers, but rather than looking for a true voltage incrementally, they look to maintain the specific ratio of open circuit voltage you, the user, dictate. This can result in similar results to MPPT but can also be less efficient in some cases. 


Advantages/Disadvantages of Solar Charger Controllers



The main advantage of PWM controllers is their cost. These controllers are less complex and easier to manufacture. This leads to a smaller price tag. The biggest disadvantage of this controller is its lack of flexibility. If you experience variable light conditions and the controller drops the voltage into a battery when a solar panel is shaded, it will not boost that voltage back up once the obstruction is clear.



The main advantage of MPPT controllers is their "smart" technology that allows voltage to fluctuate depending on what results in the most energy collection. This means you get more energy into your battery, no matter the conditions. It will always work as hard as possible in your given conditions. The main disadvantage of MPPT controllers is their cost. These controllers are more advanced and are more complex to manufacture. Another thing to be aware of is the variability in build quality and overall performance. With any piece of technology, many products that claim to be "the same" can vary greatly. Before determining the best solution for your application, test, test and test again.


Ratio Power Point

The main advantage, much like MPPT, is the ability to remain agile and adjust to conditions. The main drawback is that it will almost always be less efficient than MPPT controllers making it a firm middle choice between these three options. 


When determining what solar charge controller to select, customization is vital.


While many electronics companies manufacture controllers, few do so with solar in mind maximizing efficiency at every step. Ensuring that your systems fit together and operate at an optimum level.


PowerFilm has been in the solar industry for nearly 30 years and understands the many unique mobile energy challenges you face. We can design a custom solar panel for you and an entire system that eliminates unnecessary frills and focuses on what is important to you, leading to a less expensive, more efficient product. 


When looking to create an off-grid solar solution, let us design an innovative energy solution completely tailored to you. 


Looking for a solution? Have a question? Contact us or leave a comment below.



Categories: Solar Education