When natural gas prices are provided in $ per million Btu (HHV or Gross Heating Value) do you use the component heats of combustion that are reported in HHV as well for determining the monetary value of a fuel gas byproduct?
Natural gas typicaly runs at 1030 to 1050 BTUs per standard cubic foot. To find the cost of operation, get the performance information from the vendor as well as the local delivered cost to find the operting cost.
For example:
Firetube Boiler - 200 hp consumes 8236 CU Ft/hr
delivers 6900 lbs steam/hr at 212F
BTUs/HR (8236)(1030)= 8,483,080
Cost/hr at $8.00/1000 CU Ft.... (8.00)(8.236)=$65.89