Generally, the compressors consume the bulk of electricity in a refrigerator. If you place a warm container of foodstuff at room temperature into the fridge, the heat is taken off by hydrofluorocarbon that is compressed into the cool liquid form by the compressor. The traditional compressor is fashioned to manage peak load and multiple instances of opening and closing the fridge.
With the introduction of the Inverter technology driven compressor, it results in power savings because the inverter works like an accelerator on a bike or a four-wheeler when speed is needed, it works more, when the need is less, it also slows down but does not shut down.
The Samsung digital inverter compressor based models use around 45% less energy that the traditional one.
The other good one is the LG smart Inverter refrigerator
The other features to consider are
side by side doors(like a traditional wardrobe) helps in less power use
Check for the noise, inverter compressor-based ones are less noisy
vegetables remain fresh when the fridge has a good moisture control.
Look at the compartments including adjustable and the presence of rapid or quick freeze technology
If you have toddlers at home, then you can check for a child lock.