Page 121 - WaterSense at Work

October 2012
4-27
4.6
Wok Stoves
Equation 4-9. Water Use of Wok Stove Rinse and Reservoir Spouts (gallons per year)
= Flow Rate of Rinse or Reservoir Spout x Daily Use Time x Days of
Facility Operation
Where:
••
Flow Rate of Rinse or Reservoir Spout (gallons per minute)
••
Daily Use Time (minutes per day)
••
Days of Facility Operation (days per year)
Water Use After Retrofit
To estimate the water use of more efficient rinse and reservoir spouts, use Equation
4-9,
substituting the flow rate and use time of the retrofit rinse and reservoir spouts.
Water Savings
To calculate the water savings from the retrofit of an existing wok stove with more ef-
ficient rinse and reservoir spouts, identify the following information and use Equation
4-10:
••
Current water use as calculated using Equation 4-9.
••
Water use after retrofit using Equation 4-9.
Equation 4-10. Water Savings FromWok Stove Rinse and Reservoir Spout Retrofit
(
gallons per year)
= Current Water Use of Wok Stove Rinse and Reservoir Spouts –Water
Use of Wok Stove After Retrofit of Rinse and Reservoir Spouts
Where:
••
Current Water Use of Wok Stove Rinse and Reservoir Spouts (gallons
per year)
••
Water Use of Wok Stove After Retrofit of Rinse and Reservoir Spouts
(
gallons per year)
Payback
To calculate the simple payback from the water savings associated with retrofitting
an existing wok stove with more efficient rinse and reservoir spouts, consider the
equipment and installation cost of the retrofit rinse and reservoir spouts, the water
savings as calculated using Equation 4-10, and the facility-specific cost of water and
wastewater.