Having the main freezer on the bottom is insanely inefficient. Hot air rises, and cold air falls. When a freezer is on the top, all of the cold air is generated in that freezer, and then it falls through a channel into the main refrigeration area. It keeps both compartments cold using just one system.
Freezer on the bottom requires either a separate cooling system for the main fridge, or a series of fans that constantly draw cold air upwards, wasting electricity in the process.
Those things make it more inefficient?
Having the main freezer on the bottom is insanely inefficient. Hot air rises, and cold air falls. When a freezer is on the top, all of the cold air is generated in that freezer, and then it falls through a channel into the main refrigeration area. It keeps both compartments cold using just one system.
Freezer on the bottom requires either a separate cooling system for the main fridge, or a series of fans that constantly draw cold air upwards, wasting electricity in the process.