Home Backup Power Calculator
Calculate your estimated home backup power requirements, including battery capacity, inverter size and solar panel capacity based on the appliances you want to run.
Backup & System Settings
Select Your Appliances
Select the appliances you want to use during backup. You can change the quantity, power and operating hours for each appliance.
Your Estimated Power Requirements
Recommended System
How to Calculate Home Backup Power Requirements
To calculate the right home backup system, you need to know three main things: how much power your appliances use, how long you want to run them, and how much battery energy is available.
Our home backup power calculator estimates your total appliance load, energy requirement, battery capacity, inverter size and solar panel requirement.
How Much Battery Do I Need to Run My Home?
Battery size depends on your total energy consumption rather than simply the number of appliances in your home.
The basic calculation is:
Battery capacity must then account for inverter losses and the usable capacity of the selected battery type.
Example Home Backup Calculation
Suppose you want to operate a 40-inch TV, four ceiling fans, a refrigerator, ten 18W LED bulbs, a 1 HP water pump and an iron during a backup period.
The calculator estimates the energy consumed by each appliance according to its power and operating time. Appliances such as refrigerators, pumps and irons should not automatically be treated as running continuously for the entire backup period.
What Size Inverter Do I Need for My Home?
Inverter size should be based on both the normal running load and the startup requirements of appliances with motors.
Refrigerators, water pumps, air conditioners and some other motor-driven appliances can draw several times their normal running power when starting. Therefore, choosing an inverter based only on the total running watts can result in startup problems.
What Size Battery Do I Need?
Battery capacity is normally expressed in Ah or Wh. For a battery system, the relationship is:
For example, a 48V 100Ah battery has a nominal energy capacity of approximately 4,800Wh or 4.8kWh. The amount of energy that can actually be used depends on battery chemistry, depth of discharge, inverter efficiency and other losses.
Why Battery Voltage Matters
Larger backup systems generally benefit from higher battery voltages because the same amount of power requires less current at higher voltage.
A small system may use 12V, while larger systems commonly use 24V or 48V architectures. The correct voltage also depends on the inverter and battery configuration.
How Many Solar Panels Do I Need?
Solar panel requirements depend on the energy you need to replace and the amount of usable sunlight available.
For example, if a system needs 4,000Wh and receives approximately 5 peak sun hours with 80% overall solar-system efficiency:
If using 500W solar panels, approximately two panels would be required based on this simplified calculation.
Home Backup Power Calculator for Pakistan
This calculator can be used to estimate backup requirements for common household appliances such as fans, refrigerators, televisions, LED lights, water pumps, computers, laptops and other electrical equipment.
For an actual installation, appliance nameplate ratings, battery specifications, inverter surge capability, solar conditions, wiring losses and installation requirements should be checked by a qualified installer.
Frequently Asked Questions
How much battery do I need to run a house for 5 hours?
It depends on the appliances you want to operate and how much power they consume. Enter your appliances and operating times above to estimate the required battery energy.
What size inverter do I need for a refrigerator and fans?
The answer depends on the refrigerator's running and startup power and the number of fans. Motor startup loads should be considered when selecting an inverter.
How many solar panels do I need for home backup?
Solar requirements depend on your energy consumption, available peak sunlight, system efficiency and panel wattage. The calculator estimates both total solar capacity and the number of panels.
Is a 48V battery better than a 12V battery?
For larger systems, 48V can be more practical because it requires lower current for the same power. However, the correct voltage must match the inverter and battery system design.
Are these calculations exact?
No. They are planning estimates. Actual energy consumption and runtime can vary significantly depending on appliance efficiency, battery condition, inverter losses, temperature, wiring and motor startup behavior.
Home Backup Power Calculator
Calculate your estimated home backup power requirements, including battery capacity, inverter size and solar panel capacity based on the appliances you want to run.
Backup & System Settings
Select Your Appliances
Select the appliances you want to use during backup. You can change the quantity, power and operating hours for each appliance.
Your Estimated Power Requirements
Recommended System
How to Calculate Home Backup Power Requirements
To calculate the right home backup system, you need to know three main things: how much power your appliances use, how long you want to run them, and how much battery energy is available.
Our home backup power calculator estimates your total appliance load, energy requirement, battery capacity, inverter size and solar panel requirement.
How Much Battery Do I Need to Run My Home?
Battery size depends on your total energy consumption rather than simply the number of appliances in your home.
The basic calculation is:
Battery capacity must then account for inverter losses and the usable capacity of the selected battery type.
Example Home Backup Calculation
Suppose you want to operate a 40-inch TV, four ceiling fans, a refrigerator, ten 18W LED bulbs, a 1 HP water pump and an iron during a backup period.
The calculator estimates the energy consumed by each appliance according to its power and operating time. Appliances such as refrigerators, pumps and irons should not automatically be treated as running continuously for the entire backup period.
What Size Inverter Do I Need for My Home?
Inverter size should be based on both the normal running load and the startup requirements of appliances with motors.
Refrigerators, water pumps, air conditioners and some other motor-driven appliances can draw several times their normal running power when starting. Therefore, choosing an inverter based only on the total running watts can result in startup problems.
What Size Battery Do I Need?
Battery capacity is normally expressed in Ah or Wh. For a battery system, the relationship is:
For example, a 48V 100Ah battery has a nominal energy capacity of approximately 4,800Wh or 4.8kWh. The amount of energy that can actually be used depends on battery chemistry, depth of discharge, inverter efficiency and other losses.
Why Battery Voltage Matters
Larger backup systems generally benefit from higher battery voltages because the same amount of power requires less current at higher voltage.
A small system may use 12V, while larger systems commonly use 24V or 48V architectures. The correct voltage also depends on the inverter and battery configuration.
How Many Solar Panels Do I Need?
Solar panel requirements depend on the energy you need to replace and the amount of usable sunlight available.
For example, if a system needs 4,000Wh and receives approximately 5 peak sun hours with 80% overall solar-system efficiency:
If using 500W solar panels, approximately two panels would be required based on this simplified calculation.
Home Backup Power Calculator for Pakistan
This calculator can be used to estimate backup requirements for common household appliances such as fans, refrigerators, televisions, LED lights, water pumps, computers, laptops and other electrical equipment.
For an actual installation, appliance nameplate ratings, battery specifications, inverter surge capability, solar conditions, wiring losses and installation requirements should be checked by a qualified installer.
Frequently Asked Questions
How much battery do I need to run a house for 5 hours?
It depends on the appliances you want to operate and how much power they consume. Enter your appliances and operating times above to estimate the required battery energy.
What size inverter do I need for a refrigerator and fans?
The answer depends on the refrigerator's running and startup power and the number of fans. Motor startup loads should be considered when selecting an inverter.
How many solar panels do I need for home backup?
Solar requirements depend on your energy consumption, available peak sunlight, system efficiency and panel wattage. The calculator estimates both total solar capacity and the number of panels.
Is a 48V battery better than a 12V battery?
For larger systems, 48V can be more practical because it requires lower current for the same power. However, the correct voltage must match the inverter and battery system design.
Are these calculations exact?
No. They are planning estimates. Actual energy consumption and runtime can vary significantly depending on appliance efficiency, battery condition, inverter losses, temperature, wiring and motor startup behavior.