Appliances used in the kitchen can be electrical or mechanical. Mechanical devices, such as gas cook tops, hand-operated cutters and knives are a green option, as these do not involve any power efficiency.
Electrical kitchen appliances are also often okay in terms of energy efficiency, unless they are very old.
You can buy a used gas-cook top and save some money. Unless it is an extremely old design, the efficiency of gas stoves do not vary much. It is very important to check for leaks. Also, if it has auto-ignition, check to see whether it is working properly or not. You can always use a normal lighter if it is not working.
For ovens, avoid the older round ones that barely have any insulation and are hence not efficient. Look for modern oven-toaster-griller models that have lower power consumption and also better controls such as temperature settings and timer.
In case of electric chimneys, have a look at the filters and cleaning mechanism. Older technologies may not be very convenient to maintain as they may get clogged very soon. Auto-clean is a good buy.
Mixer grinders are also available in the used market, but finding one in good shape requires patience. It is important to carefully check every jar and blade. Turn it on at the highest speed and check if the vibration is acceptable or not.
Induction cookers are more efficient than gas cook-tops. While buying a used induction cooker, make sure to check every touch and felt tip buttons as they are generally difficult to repair.
Same goes for microwave ovens, make sure all the buttons and modes are working properly. Also, check the glass turn-table plate for signs of damage.
For every appliance, always check how the company’s service backup is, especially for appliances having electronic components such as touch displays and integrated circuits boards. Please note that repairing any electrical component (wires, motors) is easier than electronics (boards, ICs, etc).