Generator Power Calculator

If you are wondering how to solve problems involving Generator Power then you have come the right place as we have come up with a wonderful tool Generator Power Calculator. Simply enter the inputs in the allotted sections of the Generator Power Calculator and click on the calculate button to get output total current, supply voltage in seconds.

Using current readings from various equipment and appliances as well as the building's power supply voltage, the generator power calculator calculates the required power. In this article, we will discuss the power generator, the working principle of the power generator, and how to utilize a generator to power a house.

What is the Working Principle of a Power Generator?

An electrical power generator (also known as a generator) turns the chemical energy of fuel like gasoline or diesel into electrical power. A detailed conversion would be from chemical energy to thermal energy, from thermal energy to mechanical work, and from mechanical work to electrical power.

Generator Power Formulas

Here are the calculations we used in our calculator now that you know what a power generator is and how it powers a house:

Power Supply Type



Direct current

Apparent Power (kVA)

V * I / 1000

1.732 * V * I / 1000


Power (Kilowatts)

V * I * PF / 1000

1.732 * V * I * PF / 1000

V * I / 1000

Motor Output Horsepower (HP)

V * I * PF * η / 746

1.732 * V * I * PF * η / 746

V * I * η / 746

How do you utilize a Generator to Power a House?

Generators can be used to power appliances in two different ways:

  • Specialized equipment for emergency situations, such as emergency lighting and ventilation. A generator with a low power rating can run only the essentials during a power outage.
  • Have a comprehensive backup connected to the house's main wiring. A high-output generator can power all of the house's appliances, including high-wattage ones.

Calculator for Generator Power

According to the generator power calculator, apparent power (kVA) is derived by combining the total current of the devices in amperes (A) with the supply voltage rating in volts (V), and actual power (kVA) is determined by using the power factor. 

Additionally, the motor's efficiency and the calculated power can be used to calculate the motor's available horsepower.

How to use a Generator Power Calculator?

You can use our generator power calculator to perform the following operations:

  • kVA to kW conversion
  • kW to kVA conversion
  • kW to horsepower (HP) conversion

For a three-phase power setup, you can also find out the kVA requirement and amperage required for your generator. In addition to volt, amp, and power factor, there are two types of electricity you can choose from single-phase and three-phase power. When a power outage occurs, you can calculate how much power your company will need using a generator load calculator.

If you want help with physics concepts you can try out our calculators on and resolve all your ambiguities in one go.

FAQs on Generator Power Calculator

1. What Size Generator Do I Need to Power a House?

With a generator rated from 5,000 to 7,500 watts, you can power even the most critical household equipment, including the refrigerator, well pump, freezer, and lighting circuits. A 7500-watt generator can power all of these devices simultaneously.

2. What is the power of a 3.5 kVA generator?

A 3,500-watt (3.5KvA) generator may power a variety of household equipment, including refrigerators, microwaves, electric furnaces, and televisions.

3. Is it possible to use a surge protector with a generator?

A surge protector can be used with a generator. If you fear a surge from your generator would damage your home's appliances and electrical equipment, the only way to prevent them is to install a surge protector. A normal 120V outlet is included with most generators.