How to choose the right power supply for your marine watermaker | Schenker Watermakers
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How to choose the right power supply for your marine watermaker

DC or AC? 12/24V or more? Here is what to evaluate in order to choose the ideal power supply for your marine watermaker.
12 Jun 2021

When you are evaluating which kind of watermaker you want to buy, one of the most important issues is to understand what is the right power supply for it. However, it is very easy to be confused by the technical vocabulary and the acronyms of the topic: direct current (DC), alternating current (AC), 12, 24 or more Volt, onboard generator, batteries, energy consumption… This might well create a lot of confusion.
In this article we will explain what are the main variables to accurately evaluate how to choose the ideal watermaker and its suitable power supply. Moreover, we will also talk about the endless variety of opportunities offered by Schenker watermakers in order to satisfy all your needs, both in terms of watermaker power supply and energy consumption efficiency.

The variables to consider | DC or AC

Sea waves and current.

DC or AC for your watermaker? The variables you have to consider

When we talk about the watermaker power supply, the necessary variables to evaluate are not so many. Nevertheless, it is really important to consider them accurately in order to avoid some mistakes in the choice. In any case, it is always a good idea to discuss the topic with a sector professional.
Having said that, here is a short list of the main variables which matter in the choice of the right power supply for your marine watermaker:

  • Watermaker water capacity: the greater the watermaker water capacity, the greater the energy it needs to work properly. For this reason, the watermakers with a water capacity lower than 60-70 l/h are usually supplied by the DC (through a 12/24V battery). On the opposite, the watermakers with a higher water capacity are usually supplied by AC (so through the connection with the onboard generator).
  • Generator onboard: with a generator already installed onboard, the most convenient choice would be to supply the marine watermaker by AC, so by connecting it directly to the generator itself. On the contrary, without an onboard generator the choice will automatically fall on the DC 12/24V supply.
  • Time of use of the onboard generator: despite the presence of an onboard generator, also its time of use may influence the watermaker ideal power supply. In fact, if there is a generator but it is barely used, the 12/24V DC power supply will be so much more convenient than AC supplying. In this way, it is possible to make the watermaker work even if the generator is turned off.
    In other words, a watermaker supplied by DC has the same functionality than a personal computer. Even if there is no energy (no generator), the PC (the watermaker) still works thanks to its battery.
  • Boat size: the onboard available space influences the power supply choice too. In fact, if you have a small or a medium-sized boat, the presence of a generator onboard (heavy and bulky) might not be a good idea. Moreover, the absence of an installed generator involves a huge save – both in terms of money and time management – and reduces the environmental impact.
    Consequently, on small or medium-sized boat, the power supply choice will automatically fall on the 12/24V DC.

Schenker marine watermakers power supply

Schenker marine watermakers, due to the presence of the Energy Recovery System (ERS, patented technology), make the choice of the suitable power supply for your watermaker way easier. In fact, the ERS guarantees an energy consumption up to 80% lower compared to traditional watermakers.
The average energy consumption of a Schenker watermaker is only 4 Watt per each liter of fresh water produced. This means that it is possible to use a 12/24V DC power supply also for those watermakers with a higher water capacity (up to 150 l/h). In this way, there is no need to install a generator onboard or, in any case, it is possible to have a smaller one.

In detail, each Schenker marine watermaker with a water capacity between 30 and 50 l/h are only available in the version 12/24V DC, because their energy consumption is so low that it would not make sense to use a generator. The perfect examples are the models Zen 30 or 50 and Smart 30.
Indeed, the watermaker with a water capacity higher than 80-100 l/h are available both in 12/24V DC or AC version. As we said above, in this case the choice depends on the presence of a generator onboard and its time of use. The ideal watermaker models are Zen 150 and Smart 100.
Last but not least, for the larger boats with an onboard generator and high drinking water needs, the best watermakers are those supplied by AC. The Schenker watermakers that match these requirements are the Modular models over 230 l/h.

Zen 30 watermakers into the Schenker production site.
Zen 30 watermakers

DC and AC, what they mean and what are the main differences

In conclusion of this panoramic about the power supply in the marine watermakers world, lets also try to clarify the last doubts (and explain the main differences) about the main protagonists of this article: the direct and the alternating current.

Direct current (DC) was invented by Thomas Alva Edison in the late 1800s. It is a kind of power which flows just in one direction (by following a precise polarity), with low and constant voltage. This is the reason why this type of current is mainly used to make function devices which requires small amounts of energy (such as home appliances and batteries).
However, since 1886, because of this low voltage and the difficulties in the long-distance transportation, the DC was gradually replaced by AC.
Alternating current (AC), invented by Nikola Tesla and Galileo Ferraris, is a type of power that does not flow always in the same direction. Rather, it alternates positive and negative pulses along a sinusoidal arc. In this way, the generated voltage is far higher compared to that generated by DC and this type of current turns out to be perfect to supply devices that require a higher amount of energy.

In the end, DC and AC are just different types of power which guarantee different voltages and are able to make function different devices. In the marine watermakers world, and even more in Schenker watermakers case, the best choice is usually a 12/24V DC supply.