Freezer blocking is a method that can save you money with your household freezer.

With the fall weather upon us this is the time when people are starting to put away the excess bounty of their garden. Vegetables that have not already been consumed need to be stored for use throughout the winter months.

Once you have bottled and/or packaged your vegetables they will have to be stored in a cold environment that is below their freezing point and at a low humidity level. A cold environment slows down the natural deterioration of vegetable matter that occurs. Most vegetables that are placed into a cold environment will go into a type of dormant state.

Obviously a cold storage room is the most economical method. It uses the winter temperatures to keep foods cold. Unfortunately its downside is that the temperature cannot be regulated. If the outside temperature changes so does the temperature inside the cold storage room. Also few modern homes have a cold storage room. It is considered unnecessary in todays fast paced society.

For those without the basement cold storage room an alternative is the household freezer. Many people use a small chest freezer for this purpose. Chest freezers seem to be the answer for many gardeners. An upright freezer will also work but they are not as efficient (or as cold) as the chest variety. Also the small chest freezer is generally less expensive than an upright of the same size.

But if you invest in a freezer is it not economical to operate if only partially full. Freezer blocking is a possible answer for this problem.

Basically freezer blocking is filling up the unused space inside the freezer. The theory is the less air inside the freezer the less electricity will be required to freeze the food. Anything that lowers the internal volume of the freezer will cause the compressor to spend less time keeping the interior cold. It would be equivalent to having a smaller freezer.

To do this cardboard boxes called blockers are placed inside the freezer. These boxes are filled with insulation. Any form of insulation will work, but basic household wall insulation (fibreglass) is most commonly used. It is both inexpensive and easily obtained. An alternative are the insulating peanuts used for shipping and packaging. Others suggest filling the boxes with old newspapers. This would work but the insulation value would be far less than the fibreglass method. Also the newspaper would pick up moisture and become extremely heavy to lift.

Whatever is used the boxes should be completely filled, and then sealed and taped shut. You do not want insulation mixing openly with food products. Also boxes of varied sizes work best because they allow you to fill up the open spaces better.

If the freezer is only half full then place the boxes either at the bottom of the freezer or all to one side. This way you have easier access to the food during the winter. Placing the boxes on top will be frustrating because you will have to remove them every time you want to get to the food.

Another way of doing this would be to place blankets or sleeping bags inside the open areas of the freezer. The insulation method is usually preferred though because it is much easier to move around boxes than an old sleeping bag.

An alternative method is to add containers of water to the freezerpartially full containers remember water expands about 10% when frozen.

This is not true freezer blocking. Rather it is a method called heat sinking. Containers of water added to the freezer will themselves freeze into blocks of ice. Every time the freezer shuts off the cold stored inside the ice blocks will help keep the food frozen. The ice should slow down the natural heat transfer between the freezer walls and the food. The colder the freezer interior the less the cold control will turn on the compressor.

Although heat sinking is good in theory I am not convinced this method really saves money.

In all of the above methods the overall affect (in theory) is to make the freezer operate less. So the less it operates the less electricity it will consume. How much can be saved by these methods has not been properly tested. The best estimate is that it could save you 5% to 15% per year.

But then, thats a pretty good saving for an hour of your time, and some cardboard boxes full of insulation.