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Load, capacity and utilization factors

Short answer

Installed capacity = 9.81×0.85×25×150 = 31.27 MW, average load = 220 GWh/8760 h = 25.11 MW. Annual load factor = 25.11/30 = 0.837; capacity factor = 220×10⁶/(31.27×8760) = 0.803; utilization factor = 30/31.27 = 0.959.

A hydropower plant receives design discharge of 25 m³/s from 150 m height. The annual output of the plant is 220 GWh. If the peak load demand is 30 MW, determine (i) annual load factor, (ii) capacity factor and (iii) utilization factor. Assume the overall efficiency of the plant equals 85% and neglect head loss in the penstock.

Installed capacity

Pinst=9.81 η Q H=9.81×0.85×25×150=31,269 kW=31.27 MWP_{inst} = 9.81\,\eta\,Q\,H = 9.81\times0.85\times25\times150 = 31,269\ \text{kW} = 31.27\ \text{MW}

Average load

Annual energy =220 GWh=220×106=220\ \text{GWh} = 220\times10^6 kWh.

Pavg=220×1068760=25,114 kW=25.114 MWP_{avg} = \frac{220\times10^6}{8760} = 25,114\ \text{kW} = 25.114\ \text{MW}

(i) Annual load factor

LF=PavgPpeak=25.11430=0.837 (≈83.7%)\text{LF} = \frac{P_{avg}}{P_{peak}} = \frac{25.114}{30} = 0.837\ (\approx 83.7\%)

(ii) Capacity (plant) factor

CF=EPinst×8760=220×10631,269×8760=0.803 (≈80.3%)\text{CF} = \frac{E}{P_{inst}\times8760} = \frac{220\times10^6}{31,269\times8760} = 0.803\ (\approx 80.3\%)

(iii) Utilization factor

UF=PpeakPinst=3031.27=0.959 (≈95.9%)\text{UF} = \frac{P_{peak}}{P_{inst}} = \frac{30}{31.27} = 0.959\ (\approx 95.9\%)

Check: CF = LF × UF = 0.837 × 0.959 = 0.803.

Answer: load factor = 0.837; capacity factor = 0.803; utilization factor = 0.959.

✓ Answer checked by Claude Opus 5.5 (high effort)

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