Propane-powered refrigerators are among the most environmentally friendly refrigerator options, but different types of power plants complicate these calculations. In terms of carbon dioxide output, propane rates slightly worse than natural gas and slightly better than diesel fuel and gasoline.
Most in-home refrigerators rely on electricity. Since they depend on fans and other moving parts, electricity provides efficient operation and the convenience of not having to replace fuel. However, refrigerators draw a significant amount of electricity, so RVs and isolated buildings often use natural gas or propane refrigerators. These types of refrigerators are typically less efficient than comparable electric refrigerators, but their ability to function without drawing electricity makes them a viable option for portable use.
However, power plants waste energy by converting heat to electricity, which reduces the environmental advantage of electrical units. Power plants that use natural gas lose some energy in this conversion, which increases the amount of carbon dioxide released. Many power plants use coal, which releases significantly more carbon dioxide into the atmosphere than propane. These inefficiencies make it difficult to determine whether a propane refrigerator is more or less damaging to the environment than an electrical refrigerator powered by fossil fuels. However, power plants that use solar, wind or nuclear energy release almost no carbon dioxide, so refrigerators powered by these plants are the most environmentally friendly.