Generator Efficiency Calculator

A Generator Efficiency Calculator is a tool used to determine how effectively a generator converts input mechanical power into usable electrical output power. It plays a crucial role in engineering, manufacturing, and energy management. By knowing a generator's efficiency, you can evaluate its performance, reduce operational costs, and plan maintenance schedules. Efficiency calculations are essential in industries where power generation is a critical process, such as power plants, renewable energy projects, and backup power systems.

formula

Basic efficiency formula:
Generator Efficiency (η) = (Pout / Pin) × 100

Where:
Pout = Output Power (watts)
Pin = Input Power (watts)

If electrical output and mechanical input are known:
Pout = V × I × PF
Pin = T × ω

Where:
V = Output voltage (volts)
I = Output current (amperes)
PF = Power factor (decimal form)
T = Torque applied to generator shaft (Newton-meters)
ω = Angular speed (radians/second) = (2 × π × RPM) / 60

General Reference Table for Common Efficiency Scenarios

This table gives quick values for common power levels without the need for a manual calculation each time.

Example

Suppose a generator produces an electrical output of 900 kW, and the mechanical input power is measured at 1000 kW.

Using the formula:
η = (Pout / Pin) × 100
η = (900 / 1000) × 100
η = 90%

This means the generator converts 90% of the mechanical energy into electrical energy, with 10% lost due to heat, friction, or other inefficiencies.

If you have the electrical parameters instead, such as:
V = 400 volts, I = 2000 amperes, PF = 0.9
Pout = V × I × PF = 400 × 2000 × 0.9 = 720,000 W = 720 kW

If mechanical input torque T = 3500 Nm and rotational speed RPM = 2000:
ω = (2 × π × 2000) / 60 ≈ 209.44 rad/s
Pin = T × ω = 3500 × 209.44 ≈ 733,040 W = 733.04 kW

η = (720 / 733.04) × 100 ≈ 98.22%

Most Common FAQs