Residential Electrical Load Calculation Easiest Process

What is an Electrical Load?

Electrical load discussion is a crucial part of electrical and electronics engineering. There is a simple term for the electrical load. If any electrical or electronic device takes electrical energy it is called an electrical load. Before wiring a house, factory, office, or other, engineers must calculate the load based on the power. If you would like to give power to the single floor to the 5th-floor building you must require load calculation. That’s why you must know the residential electrical load calculation process. However, there are different types of electrical loads these loads are obtained in an AC circuit:

  • Inductive load
  • Resistive load
  • Capacitive load
  • Combine load

What are the Types of Electrical Loads?

There are two main types of electrical load but these are sub-divided into many factors.

Nature of Electrical Load

  • Inductive load
  • Resistive load
  • Capacitive load
  • Combine load

Electrical Power System Load

  • Domestic/residential load
  • Commercial load/municipal load
  • Industrial load
  • Agricultural load

How to Calculate Residential electrical load?

Indeed electrical load is any component of a circuit that consumes electrical energy. But, can you calculate home electricity load? Yes, there is the easiest process to calculate home electricity load. Let’s see the residential electrical load calculation process. If you would like to calculate residential electrical load then you have to find some important things, such as power, current voltage, number of devices, specific watt of these devices, and others.

Let’s see an easy way to calculate residential electrical load calculation example. Suppose you want to calculate a 15-floor residential load those have 60 units. Each unit contains 40 watts of 100 tube lights, 4 pieces of the 60-watt fan, 2 pieces of 1 ton AC each AC contains 1500 watts), 2 pieces of the 350-watt refrigerator, 1000 watt 1 Geiger, 10KW 1 lift, and 4 HP 2 pump. How much KW load is required? How much KVA load is required?

Let’s make a solution

First of all, you have to figure out every unit load of this residence.

  • Total light load = 40 * 100 = 4000 watt
  • Total fan load = 60 * 4 = 240 watt
  • Total AC load = 1500 * 2 = 3000 watts (if 1 Ton AC contains 1500 watts)
  • Total refrigerator load = 350 * 2 = 700 watt
  • Total Geiger load = 1000 * 1 = 1000 watt
  • So, total load of each unit = 4000 + 240 + 3000 + 700 + 1000 watt

Total load that we get from each unit = 8940 watts or 8.94KW

Now let’s figure out the common load of this residential

  • We have gotten 4 HP 2 water pumps = 1HP = 746 watt
  • Then we get 4 HP * 746 watt = 2984 watt
  • We have gotten 2 water pumps = 2984 * 2 = 5968 watt or 5.968KW
  • We have gotten 1 lift that contains 10 KW
  • Now total common load = 5.968KW + 10KW

Total common load = 15.968KW         

In this case, we have to calculate the total unit load. There were 60 units in that residence.

  • Now a total load of each unit * 60
  • 8940 watt + 60 = 536,400 watts or 536.4 KW
  • In this stage, we have to find the total load of the residence
  • Total load of the 60 units + common load

The total residential load is 536.4 KW + 15.968KW = 552.368 KW

The residential load is 552.368 KW. Now we have to convert it into KVA. In this case, we have to use a formula. If we divide the total load of the residence (KW) by the power factor (PF) then we will get the KVA. Suppose our residential power factor value is 0.80 then we will get

552.368 KW/0.80 =   690.46 KVA

Finally, we require = 690.46 KVA load demand

It is noted that it is the easiest and standard way to load calculation for house. So, follow this way and find the Watt, KW, and KVA of any small to large residence.

What is an Electrical Load Calculation Formula?

residential load calculation process

The electrical load balancing formula is Electrical Load (P) = Voltage (V) x Current (I). This electrical load balance calculation formula is used to figure out power, voltage, and current in any circuit. This formula was invented by Ohms. However, an electrical load calculation formula is a mathematical equation used to determine the amount of electrical power to operate a specific electrical system or equipment. The general formula for calculating electrical load is:

Electrical Load (P) = Voltage (V) x Current (I)

P = VI

It is Ohm’s law that is used to find power, voltage, and current in a circuit


Voltage is the electrical potential difference measured in volts (V)

Current is the rate of flow of electrical charge measured in amperes (A)

The electrical load or total power is (P)

If you would like to calculate the electrical load of a specific device, you must require knowing the rated voltage and current of the device, which can typically be found on its label or in its user manual. For example, if a device has a rated voltage of 120 volts and a rated current of 5 amperes, its electrical load can be calculated as:

Electrical Load = 120 V x 5 A = 600 watts

Therefore, the device requires a power supply of at least 600 watts to operate. It is important to ensure that the electrical load of a system or equipment does not exceed the capacity of the power supply, as this can lead to overheating, damage, or even a fire hazard. However, it is a total connected load calculation process for the residential.

Why Do You Need to Calculate Electrical Panel Load?

Electrical load calculation is used to calculate electrical properties, such as voltage, current, and power. If you would like to install anything in your home, offices, factory, and some other else then you must calculate the load. The electrical panel load calculation will let you know how much power you need, or how much KVA you need to run your load. For this reason, load calculation is so important before installing.  

Do I need an Electrical Load Calculation Worksheet?

Yes, if you would like to install something, you should calculate the load specifically to run your load smoothly. In this case, you should use a datasheet or worksheet. It is because it will help you to determine the electrical load requirements for your house. It is noted that if you calculate a small load then you don’t require a datasheet. But if you install medium and large-scale residential loads then you can use a residential load calculation worksheet to calculate the load then you should use a worksheet or datasheet. Here are some specific reasons why you can use worksheets.  

  • Building a new home or commercial building
  • Adding new electrical circuits
  • Upgrading an existing electrical system

Show 200 amp Panel Load Calculation Process

Calculating the load for a 200 amp panel involves a strategy. Now we will see that with an example. First of all, determine the total square footage of the building that the panel will serve. The second thing is to calculate the total load demand by multiplying the square footage with the applicable wattage per square foot. It is noted that this wattage will depend on the type of space and the electrical needs of the equipment being used. Let’s see some common wattage values for different types of spaces:

  • Residential: 3-4 watts per square foot
  • Commercial: 5-8 watts per square foot
  • Industrial: 8-10 watts per square foot

Suppose the space is a residential home with 2,000 square feet, the total load demand would be 2,000 x 4 = 8,000 watts. On the other hand, if you wish to find voltage current and power specifically then use Ohm’s law.

P = VI

Electrical Load (P) = Voltage (V) x Current (I)

What do You know about Electrical Load Calculation?

Electrical load calculation is the process of determining the amount of power that a building or facility will require to operate all of its electrical equipment and appliances. This is an important step in the design and installation of electrical systems, as it helps ensure that the system is properly sized to meet the demands of the building.

Which Factors Need to be Considered to Calculate Load?

There are several factors that need to be taken into consideration when calculating electrical load, including:

The Size of the Building

The total square footage of the building will have a significant impact on the electrical load, as larger buildings will generally require more power to operate.

The Types of Equipment and Appliances in the Building

Different types of equipment and appliances have different power requirements, and the total electrical load will be affected by the number and types of devices that will be in use.

Number of People in the Building

The number of people in the building will impact the electrical load, as more people will generally mean more devices in use.

The Expected Usage Patterns

The expected patterns of usage for equipment and appliances can impact the electrical load, as some devices may be used more frequently than others. To calculate the electrical load, the power requirements of all the devices in the building need to be added together. This includes both the running and starting currents of each device, as well as any other factors that may impact the electrical load. Once the total power requirement has been determined, an appropriately sized electrical system can be designed and installed to meet the load demand.

Do You know the Demand Factor Formula?

Yes, the Demand factor = maximum demand/total connected load. Let’s see an example suppose the maximum demand is 100KW, and the total connected load is 150KW. In this case, demand factor = 100KW/150KW

Demand factor = 0.666KW

It is noted and remembered that the demand factor is always less than or equal to 1.

Why demand factor is less than or equal to 1? Because the maximum demand is always less than the connected load in the electricity generating station. But why need a demand factor? It is noted that the demand factor plays a crucial role to know the power plant equipment capacity.

What is the Demand Factor for Residential Loads?

If you would like to find the demand factor then you have to apply a demand load calculation formula or load demand calculation formula.

Demand factor = maximum demand of the residential/connected load of the residential

If your residence has a maximum demand of 1700 watts and the total connected load is 2000 watts.

Demand factor = 1700 watt / 2000 watt = 0.85

Final Thought

Load calculation is a crucial stage before installing something. It is necessary for small, medium, and large-scale installation purposes. In this case, you need to electrical load analysis and you can see the residential electrical load calculation spreadsheet to exact calculation. However, we have given and clarified the electrical load calculation formula with an example. It may help you to find the electrical load successfully.

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