Page 390 - Sustainable On-Site CHP Systems Design, Construction, and Operations

Equipment Item Expense per Hour Revenue per Hour
Cogeneration unit Natural gas Cogen gas cost
Electricity Electricity revenue
HRSG Steam Campus steam revenue
Cogeneration unit Fixed cost
Duct burner Natural gas HRSG gas cost
Steam Campus steam revenue
Electric chiller Electricity Chiller electricity cost
Cooling energy Campus cooling revenue
Total “Expense 2” “Revenue 2”

TABLE 22-8 Evaluation Model for One Cogeneration Unit with Duct Burner HRSG

Equipment Item Expense per Hour Revenue per Hour
3
Cogeneration units Natural gas R × 1710 m × 2
g
Electricity R × 4700 kWh × 2
e
HRSG Steam R × 50 klb
s
Cogeneration units Fixed cost
Absorption chiller Steam R × (50 klb − campus steam)
s
Cooling energy R × (50 klb − campus
c
steam)/18 lb/ton-h
Total “Expense 1” “Revenue 1”
TABLE 22-9 Data for Two Cogeneration Units and Absorption Chiller

Equipment Item Expense per Hour Revenue per Hour
Cogeneration unit Natural gas R × 1710 m 3
g
Electricity R × 4700 kWh
e
HRSG Steam R × 25 klb
s
Cogeneration unit Fixed cost
Duct burner Natural gas R × (campus steam − 25 klb) ×
g
3
31.35 m /klb
Steam R × (campus
s
steam − 25 klb)
Electric chiller Electricity R × (50 klb − campus steam)/
e
18 lb/ton-h × 0.7 kWh/ton-h
Cooling R × (50 klb−campus
c
energy steam)/18 lb/ton-h
Total “Expense 2” “Revenue 2”
TABLE 22-10 Data for One Cogeneration Unit with Duct Burner HRSG

363