FOR HOME & SMALL BUSINESS
Your day.
Your energy needs.
Start with the appliances you use.
Build a clearer picture of your load, daily consumption and backup needs.
What do you use?
Choose an appliance, then adjust its quantity and wattage. Suggested values are examples; your device’s label or measured draw is a better starting point.
Add a different appliance
Your appliances
None addedYour list starts here. Add an appliance above to see your connected load.
Give your day some shape.
Estimate the hours each appliance is used in daylight and after dark. For appliances that cycle on and off, adjust their average running percentage.
Keep the essentials running.
Choose what you need during a power cut. A backup estimate is optional—you can finish with your daily energy estimate.
Battery assumptions
Illustrative settings, not a battery specification. Adjust these for the battery and inverter being assessed.
No solar charging is assumed during backup. Battery ageing, temperature and additional reserve margins are not modelled.
UNDERSTANDING THE ESTIMATE
Useful numbers.
Clear assumptions.
What do kW and kWh mean?
kW describes power at a moment in time. kWh describes energy used over time. A 100 W appliance running for 5 hours uses 0.5 kWh. The planner totals wattage × quantity × hours × average running percentage, then divides by 1,000.
Why adjust the running percentage?
Refrigerators and air conditioners do not always draw their rated power continuously. The percentage is a simplified average: 40% treats 10 hours connected as 4 equivalent hours at the stated wattage. Actual consumption depends on the appliance and conditions. Starting demand can still be much higher.
How is battery capacity estimated?
The selected backup appliances’ average power is multiplied by backup hours. This energy requirement is divided by the usable battery fraction and conversion efficiency. It assumes those appliances maintain that average use throughout the outage. Battery kWh and inverter kW are separate requirements; starting loads and actual equipment limits need checking.
Will this tell me which solar system to buy?
This is a preliminary energy estimate. It does not calculate solar generation, savings or a final equipment recommendation. A site assessment, roof conditions, actual load profile and equipment specifications are needed for that decision. For industrial facilities, start with your bills and operating schedule in a conversation with NAT.