Since inverter controlled compressors don't just turn on and off but instead keep the compressor running and varying the speed they are more efficient.
No doubt. I have measured one of my inverter refrigerators drawing as little as 2 watts.
Another plus to the technology is, there is much less variance in temperatures, inside the refrigerator / freezer, due to the compressors "always on". Old style compressors, allow the temperatures to drop several degrees inside, prior to starting.
Inverter based refridgerators are rare in the US. I've heard of some people ordering Panasonic inverter based refridgerors from Mexico (they're made in Mexico) for use in solar powered homes.
If you are living off-grid, using wind, sun, or hydro to generate your power, no doubt, these are the refrigerators to buy.
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Great reply, regarding the technology. Thanks for posting it.