Fuel equivalent for steam and power

Fuel equivalent for purchased power is assumed to be 9090Btu/kWh compared with the normal conversation factor of 3414Btu/kWh. This assumption implies power generation loss of 5676 (= 9090 — 3414) Btu for each kWh imported. Thus, power generation loss is 17.9MMBtu/h for 3.15 purchased. The rationale for this assumption will be discussed later with the FE calculation given in equation (3.7). 

Furnace stack loss is calculated based on actual heater efficiency. For this example, 55% furnace efficiency is assumed for the charge heater and the diesel stripper heater, which have a radiant section only. A furnace efficiency of 85 % is used for the product fractionator heater and the debutanizer reboiler heater, which have both radiant and convection sections. 

The mechanical losses for pumps and motors are calculated based on motor efficiency, which is assumed at 90% for this example. 

Net energy input = Energy input Energy export. 

For the example in question, net energy input = 819.2 — 77.7 = 741.5 MMBtu/h. Let us define specific energy use the same as the energy intensity  

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