Power outages are one of the biggest factors disrupting our daily lives and business operations. Having a reliable generator is the strongest safeguard against planned or unplanned outages, ensuring both home comfort and business continuity.
However, choosing a generator isn’t as simple a decision as you might think. Many technical details need to be considered, from engine type and sound insulation to fuel efficiency and capacity calculations. A device purchased without considering the correct generator specifications will either be insufficient and unable to activate in critical moments, or it will be excessively powerful and costly, straining your budget.
How to Calculate Generator Capacity for Home and Business?
The most important detail to consider when choosing a generator is accurately determining the power you need or may need. Capacity is expressed in kVA.
Power Detection (Watt)
First, you need to make a list of all the electrical appliances that must be used while the generator is running. Each appliance’s label (or instruction manual) will indicate how much power (in Watts) it consumes. You should add essential appliances like a refrigerator, boiler, lighting, modem, and TV to the list.
De-meraj Current (The Most Important Detail)
Motorized appliances (refrigerators, air conditioners, boilers, water pumps, freezers) draw 2 to 5 times more starting current than their normal operating power when they are first started. If your generator cannot handle this instantaneous high power, it will not be able to start the appliance or it will malfunction.
For example, a refrigerator that normally consumes 700W may draw 2000W (2kW) of power on its initial start-up. Therefore, calculating based solely on operating power is a major mistake.
Determining Total Power
For home use, you should consider the total power of non-motorized devices such as lighting, modem, TV, and boiler. Then, add the starting power of motorized devices.
For workplaces, computers, servers, production machinery, and air conditioning systems must be taken into account. At this point, obtaining a professional site survey eliminates the risk of choosing the wrong generator.
Safety Margin
You should always add a safety margin of 20-25% to the total wattage you find. This is because continuously running the generator at 100% capacity will rapidly reduce the engine’s lifespan.
Diesel or gasoline? Which generator type is suitable?
The type of fuel a generator uses directly determines both its performance and operating costs. Both types have their own advantages and disadvantages.
Advantages of Gasoline Generators:
They are cheaper.
They are generally lighter and more portable.
There is a wide range of options in small capacity models.
Disadvantages:
Fuel consumption is much higher than diesel.
Engine life is shorter (they wear out faster).
Gasoline is a more volatile and dangerous fuel than diesel, making storage risky.
Area of Use: Suitable for low-capacity, short-term (1-3 hours a day) and emergency needs. Ideal for camping, gardening, and small businesses.
Advantages of Diesel Generators
They are much more efficient; their fuel consumption per kilowatt is 30-50% less than gasoline.
Their engines are more robust and have a much longer lifespan (thousands of hours).
They are suitable for intensive and continuous (24/7) operation.
Diesel fuel is safer to store.
Disadvantages
They are more expensive.
They are heavier and generally noisier (except for enclosed models).
Areas of Use: Diesel generators are always recommended for full backup in homes, workplaces, apartments, workshops, and anywhere uninterrupted power is needed. In the long run, they pay for themselves through operating costs.