Cool Boxes
Cool boxes are becoming more and more popular in the home, in business and in leisure activities. As householders and business owners look for ways to preserve food with less use of power, and as camping holidays and similar leisure activities become more common, cool boxes are becoming increasingly used. There are too main types: polystyrene cool boxes and non-polystyrene cool boxes. The latter are sometimes powered.
Polystyrene Cool Boxes
The most basic type of cool boxes are polystyrene cool boxes. These are boxes of a variety of shapes and sizes, most often made of standard white expanded polystyrene. Their main properties are that they are lightweight and that they are relatively effective insulators: this makes them perfect for short term transport of frozen and perishable foodstuffs. Their capacity is generally a few litres.
One example of their use is in the local deliveries carried out by a home food delivery service. The use of polystyrene cool boxes allows the delivery of frozen items to addresses close to the depot without the need for a refrigerated truck; it also allows the delivery of chilled items such as milk, cheese and other dairy products to a wide area with much less chance of spoilage.
Polystyrene cool boxes are also used in business to business transport. Many food suppliers now use them in transporting their goods, sometimes even when refrigerated trucks are being used. Not only does this ‘double refrigeration’ method ensure that food is kept at the correct temperature, it allows delivery to clients that may not always be present to receive delivery of the goods.
Another major use of polystyrene cool boxes is in transporting sensitive medicines and medical items, such as organs for transplant. It is evident that such polystyrene boxes are required of much higher quality than the standard ones used for transporting food.
Camping Cool Boxes
Camping cool boxes follow the same principles as polystyrene cool boxes, but have a few differences. Being designed for medium-term food storage rather than short term food transport they are usually much bigger, with capacities a tens of litres rather than only a few litres. They are also constructed from different materials: rather than being made of polystyrene, they are made from high-grade plastics with excellent insulating properties. This means that their ability to keep food and drink cool is almost invariably better than is the case with simple polystyrene boxes, however this is reflected in the price, with camping cool boxes being significantly more expensive.
Electric Cool Boxes
Electric cool boxes are a further extension of this principle. Rather than being simple polystyrene boxes, they are robust boxes made of high grade plastics. Their ability to keep food cold is further enhanced by the fact that when connected to a power supply they have inbuilt refrigeration. In effect they are small, portable refrigerators.
Electric cool boxes are primarily intended as an aid to comfort on long holidays and recreational trips, hence they are adapted for use on boats, and in cars and recreational vehicles. They can be powered from car batteries and boat batteries, so a 12v cool box is standard for most motorhomes and yachts. 24v versions are also available, and many cool boxes of this type now have the option of running from household mains electricity, meaning that electric cool boxes can often be used as a backup if a home refrigerator has failed.