Refrigerated containers - how they work | Compendium of knowledge on maritime transport

Principle of operation of a refrigerated container

Refrigerated containers, also known as reefer containers, are specialised transport solutions that allow the temperature inside the container to be kept low, regardless of external conditions. Their operation is based on the use of advanced refrigeration technology, which enables temperature-sensitive goods to be transported over long distances.

Central to the technology is a cooling unit that regulates the temperature inside the container. This unit can not only reduce the temperature, but also maintain it at a constant level or heat the space if necessary. The system is controlled by a thermostat, which allows the appropriate temperature to be set and maintained depending on the type of goods being transported.

In addition, refrigerated containers are equipped with special seals and insulating walls that minimise heat exchange with the environment. As a result, even at very high or low outside temperatures, there is an optimum climate for the products being transported inside the container.

Which commodities require refrigeration?

Sea transport in refrigerated containers is essential for many types of goods that, due to their characteristics, must be stored and transported at controlled temperatures. The most commonly transported products include:

• Fruit and vegetables: They often require low temperatures to remain fresh and prevent spoilage during transport.
• Dairy products: Milk, cheese and other dairy products must be stored at a low temperature to prevent bacterial growth.
• Meat and fish: These are particularly sensitive goods which, without adequate cooling, quickly lose their properties and become unfit for consumption.
• Medicines: Many pharmaceuticals require stable thermal conditions to remain effective.

The use of refrigerated containers in maritime transport allows the highest quality and safety of transported products to be maintained, which is crucial for many industries, including food, pharmaceuticals and electronics.

Technical and energy conditions

Refrigerated containers are built in a way that maximises their energy efficiency and technical reliability. Here are the main technical and energy aspects to consider:

Technical specifications

Every refrigerated container is equipped with chillers that must meet certain performance standards. These chillers often operate on the principle of heat exchange, using refrigerants to lower the temperature. The design of the containers also plays a key role - they must be properly insulated and have seals that prevent heat transfer.

Energy requirements

Refrigerated containers require a constant source of power to keep the refrigeration system running. In the case of shipping, power is usually supplied by ships, which must be equipped with appropriate electrical sockets. It is also important to regularly monitor the condition of the container and refrigeration system to ensure continuous operation and minimise the risk of failure.

Energy management in refrigerated containers

Modern energy management systems for refrigerated containers enable the automation of a number of processes that reduce energy consumption while providing the necessary conditions for the goods being transported. These systems can adapt the operation of refrigeration units to changing external conditions, resulting in greater energy efficiency.

More information on refrigerated container technology and applications can be found on the websites of institutions such as the World Shipping Council, INDA, a leader in transport innovation and maritime infrastructure.