I have been thinking about stuffing the empty space in freezers with jugs of water. Folks all over the internet keep saying that filling the empty space in a freezer makes it more efficient.
This makes no sense to me, as an engineer! The power needed to freeze something is related only to the weight of material and the energy needed to change water into ice. The power, to keep stuff frozen, depends only on the amount of heat that sneaks into the freezer, not on what is in the freezer. The keep it cold energy does not depend on how full or empty a freezer is.
It has been suggested to me, that my thinking is off.
When I think freezer, I think of the chest freezer out on our back porch that has a top lid that opens for access. Most folks think of the freezer section of their stand up refrigerator that is typically located in the kitchen.
If you stand in front of the monster in the kitchen, wearing your bare feet, you feel the cold air fall out of the freezer when you open the door. Yes, warm air moves in to replace any cold air that fell out on your toes. That warm air does need to be cooled down from house temperature to near zero F (-18C). That does take some energy, but air is not very heavy and cools down easily.
In doing some research the only manufactures instruction that I found suggested loosely packing new items in a freezer until they are frozen hard then packing it all tight together.
Freezing water jugs uses energy
Bottom line: Freezing jugs of water in a partly full freezer to make the food stay frozen longer in case of a power failure is good, but it does not save energy. The frozen water can also be used as emergency power failure drinking water when it thaws. You should replace the water with fresh every few months.
It will cost you more energy to freeze the water. You will NOT Save Energy by freezing water to fill empty space in your freezer.
Pack the frozen water bottles around the sides of a freezer. Keep the perishable food in the middle for maximum power failure protection.
Freezer blocking is a money saver
Freezer blocking is filling the empty freezer space with sealed boxes of insulation. This is a good idea. You are adding insulation that can save energy, if it is packed around the sides if the freezer with the food in the middle.
Make your own freezer blocking boxes yourself. Just stuff fiberglass or other insulation into a box, seal it with freezer tape and, poke it into your freezer. Fit it in between the walls of the freezer and the food. If you have lots of empty space, you can use milk jugs filled with foam packaging peanuts. Empty plastic milk jugs will work almost as well.
The best types of materials to use are things that do not absorb water. Water or frozen water makes poor insulation and is not sanitary to have close to your food. Cardboard boxes can be used until they get wet. Use what you have but throw it out if it gets wet.
Blocks of solid Styrofoam would work just fine but they tend to break apart when handled.
Children's toy Jumbo Foam Blocks would work for freezer blocking.
In a stand up freezer, filling the air space with insulating freezer blocks will stop the cold air from falling out and wasting energy. Make your freezer blocks out of lightweight material to prevent injury when they fall out and hit your bare toes.
Click here for a free money saving report written by the Energy Boomer titled HOW SAVE MONEY ON YOUR NEXT HEATING BILL