MadSci Network: Physics |
The answer is yes and no and also depends on what you mean with "efficient". 1. The bottles will bring extra heat in the freezer and electrical energy is needed to get that heat out again. The "short term energy efficiency" is reduced. 2. When the bottles are once frozen, they do not have any impact on the electrical energy that the freezer needs to keep its inner room cool. The "long term energy efficiency" is not affected. 3. The frozen bottles may cause another (small!) effect. They might hinder a good air exchange within the freezer and that possibly makes it harder for the freezer to cool down other goods. The cool-down time might get a bit longer. (The details of that effect are not very clear to me as the frozen bottles also have a certain "heat capacity" (and "latent melting heat") that make things rather complicated.
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