Waterless Wok Introduction

All wok cooking requires some water.  The “waterless” wok is named as such because it greatly reduces water use in many ways.  Most notably, the waterless wok does not use water as a means to cool the equipment.  Conventional wok stoves use water for two main purposes: 

1.  Cooling the stove top – as wok stove burners generate high levels of heat for fast meal preparation, water flows across the cook top to absorb excess heat that could damage the equipment. This water which typically flows at 1 gallon per minute constantly flows while the restaurant is in operation.  This can equate to more than 700 gallons per day (2.6 m3) , or 300,000 gallons (1,135 m3) annually per stove.

 2.  Cleaning the wok – the wok is rinsed between each dish that is prepared. A small amount of water is also used for cleaning the cook top. Typically, this cleaning and rinsing water accounts for approximately 500 gallons per day (1.9 m3).

The conventional wok stove absorbs much of the heat from the high intensive gas burner under the wok.  Much of the heat gets trapped in the stove top and would cause catastrophic damage if not cooled by the running water or other means. The waterless wok stove has an air gap to insulate the equipment from the gas burner, ensuring the release of this heat to the kitchen exhaust – eliminating the need for cooling water.

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Waterless woks also feature other efficiency measures.  Most wok stoves have one or more swivel laundry-type spouts to rinse the wok between preparing dishes, these valves are often left open with water flowing as chefs do not bother to turn the water off. The waterless wok stove is fitted with a spout that shuts off water supply when it is not in use. Some wok stoves have a spout or tap at the rear to fill a reservoir. The water is typically left running when the reservoir is full. The waterless wok stove uses a knee operated ‘joy-stick’ on a timer tap to limit both the flow rate and the duration of flow to the reservoir. 

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Wok use and the water consumed varies greatly from restaurant to restaurant.   Factors affecting water use include: hours of operation, design and settings of the stove, and habits of the stove operators (wok chefs).   Sydney Water in Australia conducted a case study of a Chinese restaurant.   The 200 seat Yum Cha style restaurant operates 364 days of the year with average covers of 275 per day. It has two, 2-burner wok stoves, both were water cooled with rear swivel spouts. For the purpose of the trial, one wok stove was replaced with a waterless unit complete with cut-off spout and tap timer.  The two stoves were metered for water use and measurements were compared, with the results as follows:

Water Savings per 2-burner wok stove

Cooling water 925 gallons per day (3.5 m3)

Cleaning water 660 gallons per day (2.5 m3)

Total water 1485 gallons per day (5.6 m30

Total water savings 540,540 gallons per year, or 1.6 acre-feet (1,973 m3)

15 year life-cycle savings = 24 acre-feet(29,604 m3)

Cost of retrofit: $3,000 to $5,000

For more information on waterless woks please access the following:

Sydney Water (2006) The Waterless Wok Stove Information Sheet