There are several types of coolers that have been specially developed for use on boats, when camping, or in caravans. They differ in terms of technology, performance, energy consumption, price, and mobility, as well as their intended use. SeaHelp took a closer look at the market.
If you are only planning a day trip by boat in summer when the outside temperatures are high, a so-called passive cooler is perfectly adequate: these coolers are usually well insulated and work without electricity, cooling simply by means of pre-frozen ice packs or ice, which are placed in the cooler together with the items to be cooled.
These coolers cost between $20 and $80, are silent, do not require a power supply, and are therefore ideal for short trips or as a second cooler. The disadvantages are their limited cooling capacity (usually less than 24 hours), the lack of active cooling, and the fact that the containers are only suitable for hot temperatures to a limited extent.
However, if you are planning longer trips and do not have a built-in refrigerator or similar on board, you will need to think about adequate cooling for food and drinks – at least if you want to stay out there for a few days, for example at a quiet anchorage, or if you are planning a multi-day trip to a more remote destination.
Thermoelectric coolers have a Peltier element that generates a temperature difference
This is where so-called thermoelectric coolers come into play, which have an integrated Peltier element. A Peltier element is an electrical component that generates a temperature difference when a voltage is applied—one side becomes warm, the other cold. The so-called Peltier effect was discovered in 1834 by physicist Jean Peltier, who was the first to generate cold using electricity.
Thermoelectric coolers usually work with a 12V and/or 230V connection. The main advantages are that these types of coolers are inexpensive to purchase (approx. $50–$150), they are lightweight and portable, and some models can also heat.
One disadvantage is that these devices are dependent on the ambient temperature; they often only cool to approx. 15–20°C below the outside temperature, making them unsuitable for high demands or hot regions. What’s more, thermoelectric coolers consume a lot of electricity.
Absorption coolers can be powered by gas as well as electricity
Absorption coolers, on the other hand, can be powered by gas as well as 12 and/or 230 V. The operating principle is relatively simple: the energy heats a liquid in a closed circuit, which then evaporates and thus extracts heat.
Advantage: the devices are very quiet and, thanks to the gas, they are independent of the power grid.
When purchasing an absorption cooler, however, it should also be noted that these devices are significantly more expensive than the aforementioned coolers; prices range from 250 to 500 euros. The cooling capacity is also limited here, but only to around 25°C below the ambient temperature. The devices must be kept horizontal to operate at full capacity. And: gas operation requires increased maintenance.
A compressor cooler works like a domestic refrigerator
Finally, there is the premier class of coolers: the compressor cooler is usually a combined cooler and freezer and works like a refrigerator at home; a compressor generates a cooling cycle that can produce high cooling capacity – regardless of the ambient temperature.
The advantages of compressor coolers are obvious: they are usually very powerful; some even have a freezing function down to minus 18°C. Modern devices also have low power consumption, making them ideal for longer trips on sailing and motor boats, especially in hot environments.
However, this performance comes at a price: compressor coolers cost between $250 and $1,200, although simple devices are now available from as little as $140. It should also be noted that compressor coolers are not as quiet as the other devices mentioned; they make the same noise as a normal refrigerator when they are running. In addition, they are slightly heavier than passive, thermoelectric, or absorber coolers.
Conclusion: The most suitable cool box for a boat/yacht if you are planning longer trips is definitely a compressor cool box: it ensures high efficiency in hot weather and has relatively low power consumption. If you are planning a day trip, however, as described above, a passive cooler with ice packs or ice should be perfectly adequate.
