Hi Tim,
The propane consumption for gas ranges depends on several factors (BTU rating of the burners and usage patterns - how often and how long the range is used).
I have listed below the BTU of each burner of the cooktop and heating elements of the oven per hour at full power.
Cooktop:
Right Front: 18,000
Right Rear: 5,000
Left Front:17,000
Left Rear: 9,500
Center: 10,000
Oven:
Bake Burner: 18,000
Broil Burner:13,500
Estimate how long you will use the burner. For example, if you use the burner for 1 hour per day, at full power the consumption will be:
BTUs used per day=18,000BTUs/hour×1hour=18,000BTUs/day
If all burners are used for 1 hour in full power including the oven heating elements that will be equal to 91,000 BTUs/day.
To convert BTUs to gallons of propane, use the conversion factor that 1 gallon of propane contains approximately 91,500 BTUs.
91,000 BTUs per day/91,500 BTUs per gallon = .9945 gallons of propane per day.
To estimate annual propane consumption, multiply the daily usage by 365 days in a year:
.9945 gallons per day X 365 days per year = 362.99 estimated gallons of propane per year.
If your daily usage differs (e.g., you use the range for fewer hours or fewer burners), or you are using a lower number of burners or less time per day, adjust accordingly.
Leo