When building a solar system, one indispensable accessory is the solar charge controller. It protects the battery from overcharging which can lead to damage. In other words, it serves as a regulating bridge between your solar panel (energy source) and the battery (energy storage). Some charge controllers come with additional functionalities like compatibility with an app and Bluetooth. Since this is an important unit in your solar system, finding the right one is paramount.
The right solar charge controller will depend on your volt rating, amperage, and the type of battery you are using. All this information can seem like a lot and make it more difficult for you to make a choice. We are here to make that process easier for you. From maximum current to voltage rating, below is a selection of the best solar charge controllers for different types of users.
What do solar charge controllers do?
A solar charge controller works like a regulator. It regulates the current reaching the battery from the solar panels to avoid undercharging or overcharging. In other words, it ensures a fairly constant flow of energy to the battery. When the battery is fully charged, it cuts off the energy coming from the solar panel to prevent overcharging. The best solar charge controllers also make sure that energy is flowing in the right sequence i.e. prevents backward flow of power from the battery to the solar panels at night.
Which is better MPPT or PWM?
There are two types of solar charge controller technology namely Pulse Width Modulation (PWM) and Maximum Power Point Tracking (MPPT). The way the technologies work differs slightly. MPPT is usually more expensive—but paying the extra may not be a bad idea. Below is all you need to know about the difference between the two solar charge controllers.
MPPT Solar Charge Controller
The MPPT measures the Voltage and maximum power (Vmp) of the solar panel then convert it down to the battery voltage. Since the power going into the charge controller is equal to the power outflow, dropping the voltage to match that of the battery leads to the raising of the current. This allows you to use more available power from the panel.
PWM Solar Charge Controller
The PWM charge controller work by connecting the solar panel directly to the battery. The solar panel matches the charge of the battery. As the battery charges, the voltage rises and so does the voltage supplied by the solar panel to match that of the battery.
Best solar charge controller reviews
The capacity of the solar setup you intend to put up will determine the type of charge controller you should buy. Since they come in a wide range of prices, you might fall for the best price. However, the first thing you need to do is to make sure that your solar controller is of the right capacity and the design is easy to use. Without further ado, here is our selection of solar charge controllers grouped based on where they best fit in.
Vitron SmartSolar MPPT (Bluetooth) – Best solar charge controller
- Built-in Bluetooth
- PV input of up to 100V
- Support remote configuration using a smartphone
- Suitable for 12/24V battery
The Vitron SmartSolar MPPT solar charge controller is arguable the best solar charge controller on the market for several reasons. The most revolutionary feature of this product is the Bluetooth management system. This gives you the flexibility of monitoring and reconfiguring your solar setup remotely using your smartphone. It makes use of the MPPT technology which ensures faster battery charging while protecting battery life.
Also, the presence of three LED lights (bulk, absorption, and float) gives your real-time report of the charging process. The LED bulbs can either be on, off, or blinking. This can help you to detect any fault with the system. Unlike other charge controllers, you can purchase add-ons for Vitron SmartSolar MPPT solar charge controller. One important add-on you should consider is the battery monitor BMV-700 series. It has an LCD with attractive pictorial information like watt, current, voltage, and more.
The fact that you need to buy an add-on to monitor battery status is already a source of concern. Also, another huge flaw with this is the closeness of the input terminals. It is almost hard to use a wire below 10 gauge without them touching each other (short-circuiting) and causing sparks. Lastly, Vitron products are usually too expensive. Besides these seeming flaws, it is one of the best MPPT solar charge controllers and a great addition to your solar system.
- Comes with a Bluetooth management system
- Faster charging using MPPT technology
- Real-time report using LED display
- Further enhancements using add-ons
- Not suitable for 10 gauge wires and below
- Input terminals are too close
Renogy Wanderer Solar Charge Controller – Best 12/24 volt solar charge controller
- Compatible with Deep Cycle Sealed (AGM), Gel, Flooded, and Lithium battery
- Backlit LCD monitor
- Built-in Bluetooth for smartphone compatibility
- 4-stage PWM charging
- USB ports
Renogy Wanderer is the best 12/24 volt solar charge controller. Besides its solid construction, it is designed to work with all types of batteries. This charge controller makes use of smart 4-stage PWM charging namely bulk, boost, float, and equalization. The benefit of this stepwise charging process is that it helps to improve system performance and increase the lifespan of your battery.
Unlike Viton, this one has an inbuilt backlit LCD screen display where you can monitor the system operations, error codes, and diverse load control. Another feature of this charge controller that can come in handy is the presence of 2x 5V 2A USB ports. You can charge your smartphone and other gadgets right off these ports. Generally, it protects your device from overcharging, reverse polarity, reverse current, and short-circuit.
Renogy Wanderer is capable of charging over-discharged lithium batteries. It is affordable and the compact nature makes it easy for you to include in your RV solar setup. It is easy to install and is definitely one of the cheapest charge controllers out there. However, the majority of this solar charge controller’s reviews cast doubt on its durability. Also, getting support from the manufacturers can be a serious challenge—hopefully, you won’t need their support.
- Broad battery compatibility
- Offers 2x USB charging ports
- Stepwise four-step charging
- Can charge an over-discharged lithium battery
- Durability is questionable
- Poor customer support
Outback Flexmax 80 – Best 80 amps solar charge controller
- Programmable to charge from 12VDC to 60VDC
- System performance logging for 128 days
- Thermal management cooling technology
- Optional temp sensor and OutBack HUB
The Outback Flexmax makes use of advanced MPPT technology to ensure the maximum power produced by the solar panel reaches the battery. Also, the presence of an 80 character-display backlit LCD allows you to read off the operational status in real-time. The 80 amp solar charge controller allows input PV voltages of up to 150VDC. This makes it easy to charge the battery from 12 to 60 VDC. These features will come in handy for those setting up off-grid solar systems.
It supports a wide range of battery voltages and has the ability to step-down higher voltage solar arrays to recharge a battery with a lower voltage. Another useful feature is the ability to log system performance data for the last 128 days which is made available at the touch of a button. Outback Flexmax incorporates active cooling and intelligent thermal management cooling allowing the device to operate at full capacity in ambient temperature (up to 40 degrees centigrade).
There are a few optional features you can add to this solar controller for improved efficiency. This includes a remote temp sensor and OutBack HUB. Notwithstanding all these cool features, this solar charge controller has its flaws. The display is tiny and often disappointing. Also, the manual is poorly written and hard to understand. All its cool features come at a high price too. However, for an 80 amp setup, it is still your best bet.
- Logs 128 days system performance data
- Suitable for all types of batteries
- Features intelligent thermal management cooling
- Availability of optional add-ons
- Tiny LCD screen makes reading data difficult
- Poorly written manual
EPEVER 100A MPPT charge controller – Best 100 amp charge controller
- Compatible with 48V, 36V, 24V, and 12V battery setup
- Support 4 battery types (lead-acid, lithium, AGM, Gel, Flooded)
- Up to 150V maximum input voltage
- Available optional accessories
FPEVER combines multiphase synchronous rectification technology (MSRT) and MPPT control algorithm to produce this one. It boasts of high response speed and ensures maximum conversion efficiency which ultimately improves the efficiency of the solar system. So, whether your solar panels are supplying high or low power, this solar charge controller maintains high conversion efficiency. It has a cool LCD screen where you can monitor the charge input and output of your system.
There are various other features to admire in this charge controller including its compatibility with different types of batteries. It can handle a voltage input of up to 150V. It has an auto control system that limits the charging power and current so that it doesn’t go over the rated value. FPEVER MPPT charge controller has abundant opportunities for expansion.
There are numerous accessories you can add to enhance your experience including a remote temperature probe, remote WIFI control, remote Bluetooth control box, etc. FPEVER has its flaws besides the huge price tag. Inasmuch as the accessories are optional, you may soon discover that you need to get them. Also, the customer service is almost nonexistent. So, if you ever run into trouble, you’ll have to figure it out yourself. Hopefully, this will not be a deal-breaker for you.
- Combines MPPT and MSRT
- Bright and bold LCD display
- Compatible with broad battery types
- Handles up to 150V input
- Available accessories for expanded capabilities
- Limited without accessories
- Poor customer support
PowMr MPPT Charge Controller – Best 60 amp solar charge controller
- Compatible with lithium, vented, flooded, sealed, gel, NiCd battery
- Programmable input voltage
- Smart fan for heat dissipation
- 3 stage charging
The software of this PowMr has been upgraded so you should expect better performance. This upgraded 60 amp version is designed to work with all battery types. So, the user can quickly set it to their battery type. The small backlit LCD gives a real-time report on the health of the entire system which makes it a handy tool for troubleshooting.
Most of the best solar charge controllers don’t come with their fans. PowMr MPPT solar charge controller is an exception. It has an inbuilt intelligent fan that turns on automatically when the temperature exceeds 45 degrees and turns off when the temperature falls to below 40 degrees. This protects the health of your installation and prevents overheating. It offers multiple electronic protection from over-discharge, reverse polarity, overload, overcharging, and short-circuit using 3 inbuilt transformers.
MPPT solar charge controllers are indeed more expensive. However, PowMr proves that you must not break a bank to afford it. On the downside, the fan can get noisy. Also, the soldering of the terminal connectors is directly on the motherboard. So, you have to be really careful not to damage your motherboard. Finally, the customer service is really poor. However, when it works, it is topnotch.
- Up to 60 amps current output
- Comes with an intelligent fan
- Offer multiple electronic protection
- Terminal connectors are soldered on the motherboard
- Poor customer support
HQST 20A MPPT Solar Charge Controller – Best MPPT charge controller for the money
- Compatible with all battery types
- Built-in temperature protection
- External LCD screen for data monitoring
- Adjustable charging parameters
Like most of the best MPPT charge controllers, HQST is designed to work with different types of batteries. The built-in MPPT algorithm can increase energy utilization from your solar panel by 15 to 20%. This solar charge controller keeps the temperature in check by decreasing the charging current linearly as the temperature rises. Consequently, the temperature begins to fall. This action helps to prevent the charge controller from temperature damage.
This is arguably the most affordable MPPT solar charge controller, costing less than $100. Interestingly, it can automatically identify lead-acid voltage. Unlike most other products, you will need an external LDC screen to view the status and other operating data as well as modification of the controller’s parameters. Due to its unique protective functions, it can increase the lifespan of your battery.
HQST 20A solar charge controller makes use of three charging stages to ensure fast and safe charging of your battery. Although this is a solid charge controller, make sure you are buying only from reputable retailers. There have been multiple complaints of some retailers packaging refurbished product and sending it to new customers. Although this product lacks all the modern features like Bluetooth, it is a solid product for the price.
- Wors with all battery types
- MPPT algorithm increase energy utilization by up to 20%
- Highly affordable
- Makes use of 3 charging steps
- Too many imitations
- Lacks Bluetooth and remote control
PowMr 60A Charge Controller – Best 48V solar charge controller
- 4-Stage PWM charging
- Backlit LCD monitor
- Works with lead-acid batteries
- 2x USB ports
When it comes to the best 48V solar charge controller, it is hard to beat PowMr. It has a cool LCD that tells you the current and capacity. Through the LCD, you can make various adjustments including adjusting the load timer according to your need. Other additional features include recording the charge and discharge current. Also, by the side of the display, there are two 5V USB ports where you can plug in your phone and start charging immediately.
It works with a lead-acid battery. To protect your battery, the charge controller will turn off automatically as soon as your battery voltage drops below 8V. In addition to that, this charge controller protects your battery from over-charging, overload, short circuit, under-voltage discharge, and more. The compact nature makes it suitable for outdoor camping, RVs, and ships. In fact, it can fit anywhere.
Another feature that will easily draw you to this charge controller is the affordability. However, with cheaper prices often comes more problems. For PowMr 60A charge controller, the load timer is far from accurate. Also, the position for wires is so tiny that bigger wires will struggle to fit in. However, in terms of performance, it delivers as promised.
- Commpatible with 48V system
- Offers adjustable load timer
- Comes with 2x USB ports for charging your phones and tablets
- Works with a lead-acid battery
- Highly affordable
- Load timer is not accurate
- Wire inlets are tiny
ALLPOWERS 20A Solar Charge Controller – Best PWM charge controller
- Dual 5V USB ports
- Adjustable power rate
- Backlit LCD
- Compatible with lead-acid, li-ion, and LiFePO4 batteries
First off, ALLPOWERS is offering an 18-month warranty on this product. Bearing in mind how volatile charge controllers can be, this should give you a rest of mind. The two important features of this solar charge controller are charge management and a 4-stage PWM charging process. It is equipped with an industrial-grade STM 8 microprocessor to effectively control the charging and discharge process.
All electronics generate heat during operation but ALLPOWERS 20A solar charge controller uses dual MOSFET reverse current protection which has low heat production. The entire system is easy to use and understand, thanks to the LCD. It enables you to customize your settings. An important point to note is that your controller will automatically turn off if your battery goes below 8V.
This solar charge controller is designed for use with wires within the range of 26 to 12 AWG. If you have a solar setup with wires outside this range, you may face some problems. PWM is not as powerful as MPPT but for the price, it is a good investment. One interesting feature in this one is the D2D (Dusk till dawn). This automatically turns on lights as soon as the sun goes down. Arguably, the combination of all these features makes ALLPOWERS the best PWM charge controller.
- Offers charge management system
- Uses industrial-grade STM 8 microprocessor
- Inbuilt Mosfet revers current protection
- Setttings can be customized
- Comes with 18-month warranty
- Not for bigger wires
- PWM is not as effective as MPPT
ACOPOWER Midas 40A – Best MPPT charge controller
- Compatible with different types of batteries
- Maximum voltage input is up to 100V
- 4-Stage battery charging
- 18-month warranty
- Remote meter
The most unique feature of this charge controller is the Remote Meter. It can automatically identify the controller and display relevant data like the model, operational data, and the system’s working status. The presence of 6 navigation function keys makes it easier to control compared to other charge controllers with only two buttons. Also, the remote meter has a longer communication range with the charge controller. So, you can keep it in a more convenient place rather than running to the charge controller all the time.
ACOPOWER Midas 40A prevents the battery from overcharging from the solar panels and over-discharging by the load. Thanks to the MPPT technology, you will be able to harness most of the juice from the solar panel. It may interest you to know that MPPT technology has a 99.5% charging efficiency. It also protects your battery from short-circuiting, overload, and reverse current.
The charging process of ACOPOWER Midas has been optimized into 4 stages namely: bulk, boost, float, and equalization. While it is not the cheapest MPPT charge controller on the market, it is also not the most expensive too. All the Midas solar charge controller reviews have been good with only a few complaints about the customer service. Obviously, the pros far outweigh the cons.
- Remote meter ensures easy monitoring
- Remote meter has longer communication distance
- More navigation keys makes customization easier
- Optimized 4 stages charging process
- Slightly expensive
Buying Guide for the best solar charge controller
- Specific voltage: The first thing you need to consider when shopping for a solar charge controller is the nominal battery voltage. For example, you cannot use a charge controller rated 12/24V for a setup of 48V. The good thing is that most brands have products for different nominal battery voltage. So, irrespective of your setup, there is a high chance that your favorite manufacturer will have the right charge controller for you.
- Amp: Likewise, you need to pay attention to the maximum current (amperage). The maximum current will determine the amount of load the solar charge controller can handle. Basic solar charge controllers are usually rated 10 to 20A. However, there are more powerful solar charge controllers with ratings of up to 60 or 80A. Knowing what your solar charge controller can handle is crucial to avoid causing damage to your equipment.
- LCD monitor: Finally, it is important to make sure that you are buying a charge controller with an LCD where you can monitor the system data and know when something is going wrong. Most solar charge controllers have this feature but for some, you have to buy the screen separately. Make sure buying a separate monitor will not overstretch your budget.
- Your budget: While MPPT charge controllers are usually more efficient, they are really expensive. If you are on a low budget, consider buying a PWM controller. You can always upgrade when your finances permit. The secret to battery longevity and efficiency lies in choosing the right charge controller.
How many solar panels can you connect to one charge controller?
The manufacturers of solar charge controllers size and rate them by the system voltage and solar panel array current. Determining the number of solar panels you can connect to a charge controller in a simple solar setup is easy. Firstly, multiply the number of solar panels you have by their wattage to get the array’s total watts. For example, if you have two 100W solar panels in series, the total solar array will be 2 x 100 = 200 watts.
The next thing you need to do is to divide this by the voltage of your battery. For this setup you will have 200 watts / 12V = 16.67 amps. Then you need to add 25% to make room for cold temperatures. 16.67 + 25% = 20.84 amps. In this case, you can choose a 30 amp, 12VDC solar charge controller. This simple calculation will easily help you to determine how many solar panels you can use with your charge controller.
Frequently Asked Questions
- Which solar charge controller is best?
When it comes to technology, solar charge controllers that make use of MPPT technology outperform PWM. Therefore, it makes sense that the best solar charge controller should be one that makes use of the MPPT technology. One product that is hard to beat in this regard is Vitron SmartSolar MPPT solar charge controller. It has a built-in Bluetooth management system which is revolutionary.
- How do I choose a solar charge controller?
Your choice of solar charge controller will depend on your nominal battery voltage. If you have a 48V battery system, you have to look for a solar charge controller with the same rating or higher. The next thing to consider is your budget. If you are on a slim budget, going for PWM will help you to stay within your budget.
- Can I use a solar panel without a charge controller?
If you are using a solar panel with an output of less than 1% of your battery capacity with low current maintenance charging, this can be safely done. However, you will be putting your battery at the risk of overcharging.
- Can I use a solar charge controller for a wind turbine?
Solar charge controllers will not work for wind turbines. Wind turbines make use of hybrid controllers which act as power management. They can shut down or initiate turbine operation as well as coordinate a series of wind turbines.
- Can I connect solar panel directly to battery?
Connecting the positive wire from the solar panel to the positive battery terminal and the negative of the panel to the negative battery terminal will charge your battery. However, at night, the current will move from the battery to the panel which will discharge your battery. Also, the panel can overcharge the battery leading to damage. Using a solar charge controller can prevent this.
If you are already planning to set up a solar system, you already know that there are lots of accessories that you need to have too. A solar charge controller is designed to protect the entire system—especially your battery from damage. It would be a shame to spend thousands of dollars to buy a battery and lose it to an avoidable cause. With thousands of products on the market, our buyer’s guide will help you to choose the best product for your system.