Solar panel regulators are essential parts of the solar system for both your home and business. It is used to incorporate a backup battery for the solar system. For many solar systems where they are using the grid as a backup, then they do not require to have a solar panel regulator.
Here is everything you need to know about solar panel regulators before installing them in your solar system.
What exactly is a solar panel regulator?
A solar panel regulator is also known as a charge controller as well. As mentioned earlier it works in conjunction with a stand alone solar system. Additionally, it is used to manage a battery backup that is connected with the grid and solar system. And all of those solar systems which do not include batteries as a backup and only use the power grid, then these solar charge regulators are not at all necessary for this setup.
A solar charge regulator is just a small box, it has a solid state of circuitry. This box is placed between solar panels and the backup power bank or battery that we are using with the solar panel system. The circuit is very simple yet highly effective. The basic function of this circuit is to regulate the amount of charge coming from solar panels. The reason behind the regulation of the charge is very simple, the core purpose here is to stop the battery from overcharging itself.
A solar charge regulator also provides a direct connection to different appliances connected with it. While making sure that it continues to charge the battery; however, that is the case when you can run appliances directly from the box and bypass the battery bank. And also make sure that the batteries will continue to be charging.
With the boom in technology, modern solar charge regulators are highly effective and will outperform just about any main power battery charger.
Here is the list of things you should know about solar charge regulators before you install a solar system:
Identifying a right solar panel regulator:
There are many different factors affecting the decision before choosing the right size of your regulator. The first thing that you need to check is the amp ratings of your solar panels. Add these figures and that will help you get the minimum size charge controller you will require. Or you can surely hire professionals who can do this for you. Solar panels installers will surely calculate these numbers and help you recommend the best suited solar panel controller for you.
It is also very important to future-proof your solar system. Therefore, before selecting the size of the regulator you must consider whether you are going to add new panels to your solar system in the near future. These regulators are not really that easy on the pocket, so it is recommended to buy one that can be useful when you add new panels to your solar system. It can save you some additional money on the way.
Low Voltage Disconnect:
It is a smart feature for solar charge regulators. Many of these power controllers have this LVD (Low Voltage Disconnect) feature in them. Due to this feature, your box will keep an eye on the voltage derived from the battery. When the battery voltage drops to the point where the continuous drawing of voltage may damage the battery permanently, then it disconnects any load connected to the battery and saves it from any permanent damages. It is a great feature for protecting your deep cycle battery investment. Modern day batteries are designed in a way that if the discharges are too deep, then it will reduce the battery life significantly.
Maintenance of solar panel regulators:
A good quality charge regulator will require no maintenance at all; however, it is highly advisable to conduct a regular checkup for the wiring and connectors inside the circuitry, just to make sure that all the connections are properly intact and corrosion free. For a longer service life of the solar charge regulator, you must make sure that it is not placed under direct sunlight and the storage area has decent airflow. There is no doubt that advanced technology has helped improve the robustness of the solar charge regulators but extreme heat may still reduce the life of these regulators.
Additionally, for safety purposes and to protect your solar panel controller, batteries and appliances and making sure risks of fire are reduced , place a fuse between the solar panel regulator and solar panels.
So, do we really need a solar panel regulator?
To answer it in the simplest way possible, if your solar system requires batteries, then yes you need to have a solar panel regulator. If your solar system is not including the battery, then you can simply ignore solar panel regulators. The main function of the solar panel regulator is to regulate or control the charging of batteries in any battery based solar system.
In Australia, most of the residential solar systems are directly connected to the grid instead of the batteries they do not require to have solar panel regulators. That being said, all of the off grid residential solar systems and remote equipment powered by solar charged battery systems need a solar panel regulator to ensure the long life of the battery while making sure of the safety and efficiency of the battery performance.
What do solar panel regulators do?
You must be wondering that wait a minute, didn’t we just go through all of it before. The answer is kind of yes, but here we are going to discuss this in more detail. When do you know that these regulators are used mainly to charge the battery in the safest way, then why is it not called simply the battery charger? Because if you see the definition of the charger, generally, it is something that you plug into an AC outlet and connect it with the battery and it will essentially charge the battery. Chances are most of you might be having one in your garage to charge your car’s dead battery.
But the difference here is that the solar panel regulator is not a plug which is directly providing supply from the outlet; instead, it regulates it. Power coming from solar panels is in DC form and a varied DC voltage can most certainly damage any battery. This is why these are also known as solar charge controllers or DC charge controllers. Especially, when your solar system may also have an inverter in it. Therefore, you will require both the inverter charger which involves AC chagrin of the battery and a DC solar charge controller to control the flow of solar energy into the batteries.
Solar panel regulator – Water Faucet analogy:
The ultimate goal of charging any battery is very simple, it is to bring the voltage level of the battery up to the factory defined level that represents its full charge. The water Faucet analogy illustrates how solar panel regulators work. Imagine a scenario where you have to fill the glass with water. Here, the faucet is the regulator and the glass is the battery. That means, the water level in the glass represents the battery’s voltage level and the current is represented by the water flow. Till the time water level will remain low and the flow of water is slow enough, the glass will accept water. Similarly, a low battery will accept DC current.
If we turn the faucet wide open then the overflow will quickly fill the glass from the force of the water flow. This is the exact same issue faced by the battery in case of excessive DC current flow, therefore we require a solar panel regulator. It helps with the steady and continuous rise in the voltage of the battery to effectively and efficiently charge the battery without causing any damage to the batter.
Set points for battery charging:
To get more specific, a solar panel regulator regulates current into the battery depending on set points for individual batteries. These set points are specific voltage levels predefined by the battery manufacturers for every stage of the battery charging. These three points are namely, bulk, absorption and float charge stages. Solar panel regulators make sure that they keep the track of all three stages. So a battery in a depleted state is like an empty glass of water from the above mentioned analogy. Solar panel regulators feed the highest current to the battery similar to the fastest water flow of an open faucet into the empty glass, this stage is known as the bulk stage. Once your battery reaches the bulk point stage your battery is about 80% charged.
After the battery reaches 80% charging point, these controllers or solar panel regulators reduce the current flow like slow running water from the faucet to the glass of water, until it reaches the absorption set point. After this point, solar panel regulators certainly drip just enough current to keep the battery voltage at its floating set point.
Which solar panel regulator would be best suited for my needs?
There are two most popular types of charge regulators used in Australia. PWM (Pulse Width Modulation) being comparatively easier on the pocket while being highly effective but limited is one of the two types. MPPT (Maximum Power Point Tracking) is highly efficient and flexible but falls into a more expensive type.
In order to identify the perfect fit for your requirement, you will require to understand both solar panel controllers:
Pulse Width Modulation (PWM) regulators:
In a typical regular day scenario, we try to match the voltage of the controller to your battery bank. This means a 12 volt controller matches with a 12 volt battery backup system. This is the most commonly followed method for RVs and boats.
There are people who are using solar panels for their homes but with an off-grid connection. They will be required to match their regulators with a 24 volt battery backup system, similarly for 48 volt systems as well.
For these scenarios, the pocket friendly pulse width modulation (PWM) solar panel controller would be a great choice. The confusion is common at this point, let us try to explain this in detail. Suppose you choose to go with costlier MPPT regulators. It should allow you to use larger voltage solar panel arrays with a smaller voltage battery backup system. Therefore, 60 cell or 30 volt solar panels can charge a 12 volt battery backup system when an MPPT controller is used.
Maximum Power Point Tracking (MPPT) regulators:
A Maximum Power Point Tracking (MPPT) regulator feeds the maximum amount of energy produced by the solar panels to the battery backup system. It is obvious that voltage from solar panels will vary depending on the intensity of the sunlight. Even with this simple setup, an MPPT regulator can actually use all of the available energy to charge the batteries. And the reason behind this is watts = current x voltage, an MPPT regulator can adjust the voltage to match the battery by using the only current. It also allows an MPPT regulator to use a larger voltage than the backup system uses. This means, even though MPPT regulators are not as cheap as their counterparts, they get more charging bang for the buck.
In contrast, a Pulse width Modulation regulator can only use the voltage supplied by the solar panels that match the power backup system to charge the battery. Therefore, when panels will be producing more charge on better lit days, PWM will still be only using the rated voltage to charge the batteries. In layman’s terms, produced power will be wasted. Additionally, PWM can not use a higher voltage solar array to charge a lower voltage battery setup.
However, PWM is an excellent choice to charge the batteries when the produced voltage and power backup system is in sync.