Solar panels and MPPT

“Free” energy from the sun, it sounds ideal. Of course there is a purchase price for the panels, cables, fuses (holders) and MPPT, but once that investment has been made, the energy you generate is completely free, and you are no longer always dependent on shore power.

Why choose solar energy?

In addition to solar panels, many boat owners also consider wind energy, often in the form of a wind generator. From our own experience, we can say that this is not always the best choice. Wind turbines produce noise, cause resonance and often do not provide constant energy. They work well in strong winds, but they slow down in gusts, which leads to irregular peaks in amperes. In addition, the noise and resonance spread throughout the boat, which can be very annoying.

Solar panels do not have these disadvantages. Although some find them less aesthetically pleasing, there are now options that are beautiful. Brands such as Wattstunde offer completely black panels with subtle lines that look great on a boat. Even more innovative are the panels of Lightleaf, which are lightweight, curved and made of carbon. These panels can be easily attached to the sea rail, deck, wheelhouse or bimini. Due to their curved shape, wind flows underneath, which helps with cooling and therefore improves the performance of the panel.

Sustainable solar panels

At Zarcillo Smartmarine we only sell high-quality solar panels that can withstand the harsh conditions at sea. For example, the Lightleaf 110W solar panels, which are perfect for maritime use.

A common question is whether we offer 'unsellable panels'. We stand behind our products and that is why we do not offer unsellable panels. In our eyes, there are no unsellable panels because they all break and quickly perform less than promised.

Lightleaf solar panels

Solar panels

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What does Wp mean?

Wp stands for Watt peak, which is used to indicate the power of a solar panel. This is the maximum electrical power that a panel can deliver under ideale conditions. For example, a 110Wp solar panel can produce even more, such as 115Wp, in exceptionally good conditions. Actual production depends on factors such as the position of the sun, the angle of the panel, shade, cleanliness of the panel, quality and heat.

Choosing the right cables and MPPT charger

When choosing cables it is important to consider the distance between the solar panel and the battery. The longer the distance, the thicker the cables need to be to minimize energy loss. For a Lightleaf 110W panel is a 4mm² cable suitable for distances up to 5 meters. For longer distances a thicker cable, such as 6mm², are necessary to prevent voltage drop.

We recommend MC4 connectors for connecting the panels, as they are safe and waterproof. Make sure you mount the connectors correctly, using the right tools. Proper mounting is very important to prevent fire hazards. Ask us for advice or help!

In addition to cables and connectors, the choice of a charge controller is crucial. You can choose between a PWM (Pulse Width Modulation) and a MPPT (Maximum Power Point Tracking) controller.

What is the difference between PWM and MPPT?

PWM controller

A PWM controller is a simple and affordable option, but less efficient. It works by equalizing the voltage of the solar panel with that of the battery. For example, if your solar panel delivers 18V and your battery is 12V, the excess voltage is simply removed, resulting in energy loss.

MPPT controller

An MPPT controller is much more efficient and advanced. The MPPT constantly searches for the maximum power point of the solar panel, so that the panel always operates at its most efficient voltage and current, regardless of the weather conditions. This allows an MPPT controller to increase the energy yield by up to 30% increase compared to a PWM controller, especially at higher system voltages. In addition, an MPPT automatically adapts to both 12V and 24V battery banks.

What do the numbers on MPPTs mean?

You often see numbers like “75 | 15” or “100 | 30” on MPPT controllers. This indicates two important properties:

  • The first number (e.g. 75) is the maximum PV voltage (Voc), meaning this is the maximum voltage the solar panel can reach in idealand circumstances.
  • The second number (e.g. 15) is the nominal charging current, expressed in amperes.

It is important to choose a controller that suits your system.

Use the handy Victron Energy MPPT calculatorr.

Do you have specific questions or would you like tailor-made advice?

Feel free to send us an email. We will be happy to help you make the right choice for your situation on board.

Ask us for advice

Why choose a Victron SmartSolar MPPT?

To optimize a solar panel system such as the Lightleaf 110W is the Victron SmartSolar MPPT controller an excellent choice. These chargers are known for their high efficiency, reliability and smart features. Thanks to the built-in Bluetooth you can easily monitor your system's performance and adjust settings via an app. If you have a Victron If you have Cerbo and internet you can monitor this anywhere, no matter where you are.

In addition Victron MPPTs designed for harsh marine environments, making them ideally suited for marine use.

Do you have solar panels mounted on both the port and starboard sides of your boat, for example on the sea rail? Then it is wise to use two MPPT controllers. Due to different light conditions (such as shade on one side), two separate MPPTs can ensure that both panels independently deliver their maximum power, which optimizes the energy yield.

Victron MPPTs

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