Performance Calculation

Heat Rate (Energy Efficiency)
Overall thermal performance or energy efficiency for a power plant for a period can be defined as

φhr = H / E (1)

where

φhr = heat rate (Btu/kW, kJ/kW)

H = heat supplied to the power plant for a period (Btu, kJ)

E = energy output from the power plant in the period (kWh)



Thermal EfficiencyThermal efficiency of a power plant can be expressed as

μte = (100) (3412.75) / φ (2)

where

μte = thermal efficiency (%)



Capacity Factor
The capacity factor for a power plant is the ratio between average load and rated load for a period of time and can be expressed as

μcf = (100) Pal / Prl (3)

where

μcf = capacity factor (%)

Pal = average load for the power plant for a period (kW)

Prl = rated capacity for the power plant (kW)




Load FactorLoad factor for a power plant is the ratio between average load and peak load and can be expressed as

μlf = (100) Pal / Ppl (4)

where

μlf = load factor (%)

Ppl = peak load for the power plant in the period (kW)




Economic Efficiency
Economic efficiency is the ratio between production costs, including fuel, labor, materials and services, and energy output from the power plant for a period of time. Economic efficiency can be expressed as

φee = C / E (5)

where

φee = economic efficiency (cents/kW, euro/kW, ...)

C = production costs for a period (cents, euro, ..)

E = energy output from the power plant in the period (kWh)




Operational Efficiency
Operational efficiency is the ratio of the total electricity produced by the plant during a period of time compared to the total potential electricity that could have been produced if the plant operated at 100 percent in the period.


Operational efficiency can be expressed as

μoe = (100) E / E100% (6)

where

μeo = operational efficiency (%)

E = energy output from the power plant in the period (kWh)

E100% = potential energy output from the power plant operated at 100% in the period (kWh)