Capacity factor — Science definition
Defined in 2 courses:
- The fraction of the time a power source actually delivers its maximum possible output, written as a percent; intermittent sources have lower capacity factors than steady ones. (Physics & Environmental Science)
- Actual energy divided by maximum rated energy over the same interval. (Physics & Environmental Science)
Where it is taught
- Renewable Energy — Energy, Water & Material Resources, Physics & Environmental Science, Grade 12
- Life-Cycle Energy & Resource Accounting — Energy, Water & Material Resources, Physics & Environmental Science, Grade 12
In use
Capacity factor is actual energy over an interval divided by the energy that continuous nameplate output would provide during that interval.
Renewable Energy
Capacity factor equals actual energy divided by rated power times period.
Life-Cycle Energy & Resource Accounting
Questions using capacity factor
Problem 1
Answer and explanation
25 %
Capacity factor = average output / maximum output = 20 / 80 = 0.25 = 25%.
Problem 2
Answer and explanation
Generation=5×0.30×2000=3000 kWh. The allocated storage input returns 400 kWh and loses/transfers 100 kWh under the stated boundary; do not apply the storage loss to energy that bypasses it.
Generation=5×0.30×2000=3000 kWh.
The allocated storage input returns 400 kWh and loses/transfers 100 kWh under the stated boundary; do not apply the storage loss to energy that bypasses it.
Response criteria
- Use the stated measurements or conditions, with correct units.
- Connect the result to the physical or environmental mechanism or evidence relationship.
- Identify the assumption, model limit or further evidence requested.
Problem 3
Answer and explanation
Generation=5×0.30×2000=3000 kWh. The allocated storage input returns400 kWh and loses/transfers100 kWh under the stated boundary; do not apply the storage loss to energy that bypasses it.
Generation=5×0.30×2000=3000 kWh.
The allocated storage input returns400 kWh and loses/transfers100 kWh under the stated boundary; do not apply the storage loss to energy that bypasses it.
Response criteria
- Use the stated measurements or conditions, with correct units.
- Connect the result to the physical or environmental mechanism or evidence relationship.
- Identify the assumption, model limit or further evidence requested.
Problem 4
Answer and explanation
90 %
Capacity factor = 45 / 50 = 0.90 = 90%. Geothermal runs steadily, so its capacity factor is high.