My answer is based on the assumption that you are looking for an alternative refrigerator which does not require electricity.

Use can use Pot-in-pot refrigerator.

A pot-in-pot refrigerator is an evaporative cooling refrigeration device which does not use electricity. It uses a porous outer earthenware pot, lined with wet sand, contains an inner pot (which can be glazed to prevent penetration by the liquid) within which the food is placed - the evaporation of the outer liquid draws heat from the inner pot.

The device can be used to cool any substance.

This simple technology requires only a flow of relatively dry air and a source of water.

My answer is based on the assumption that you are looking for an alternative refrigerator which does not require electricity.

Use can use Pot-in-pot refrigerator.

A pot-in-pot refrigerator is an evaporative cooling refrigeration device which does not use electricity. It uses a porous outer earthenware pot, lined with wet sand, contains an inner pot (which can be glazed to prevent penetration by the liquid) within which the food is placed - the evaporation of the outer liquid draws heat from the inner pot.

The device can be used to cool any substance.

This simple technology requires only a flow of relatively dry air and a source of water.

Alternatively, you can put the vegetables in steel utensil and cover the whole utensil with clean wet cloth.

However, this alternate solution does not cool better than Pot-in-pot refrigerator.