Calculate inverter draw, appliance demand, runtime, and losses. Review watts, watt-hours, amps, and efficiency fast. Make confident off-grid and hybrid planning decisions with clarity.
| Item | Example Value |
|---|---|
| Appliance Load | 900 W |
| Usage Hours | 5 hours |
| Inverter Efficiency | 92% |
| Standby Power | 18 W |
| Battery Bank | 24 V, 200 Ah |
| Depth Of Discharge | 50% |
| Peak Sun Hours | 5.5 |
| Panel Derating | 80% |
| Required Solar Array | 1189.39 W |
| Estimated Backup Runtime | 2.41 hours |
Total AC Load = Appliance Load × Quantity
Running Input Power = Total AC Load ÷ Inverter Efficiency
AC Output Energy = Total AC Load × Usage Hours
Running Input Energy = Running Input Power × Usage Hours
Standby Energy = Standby Power × Standby Hours
Total Inverter Energy = Running Input Energy + Standby Energy
Inverter Losses = Total Inverter Energy − AC Output Energy
Battery Nominal Energy = Battery Voltage × Battery Capacity
Usable Battery Energy = Battery Nominal Energy × Depth Of Discharge
Backup Runtime = Usable Battery Energy ÷ Estimated Running Draw
Required Solar Array = Total Inverter Energy ÷ (Peak Sun Hours × Panel Derating)
Recommended Panel Count = Required Solar Array ÷ Single Panel Wattage
Enter the appliance wattage first. Add the number of identical loads. Fill in daily usage hours. Then enter inverter efficiency and standby power.
Provide your battery voltage, battery capacity, and allowed depth of discharge. These values estimate usable stored energy and backup runtime.
Add AC voltage and power factor for current estimation. Enter surge factor and safety margin for inverter sizing guidance.
Finally, enter peak sun hours, derating, panel wattage, and electricity rate. Press calculate to view energy use, losses, panel count, runtime, and cost.
A solar inverter does more than convert DC to AC. It also consumes power while operating. Some power is lost during conversion. Some is used in standby mode. These small losses add up each day. Accurate estimates help you size a battery bank correctly. They also help you choose a better solar array.
Many users focus only on appliance wattage. That is not enough. The inverter itself changes real energy demand. A 900 watt load may require more than 900 watts from the battery. Efficiency decides the gap. Standby draw matters too. Hybrid and off-grid systems often run all day. Even low idle power can raise monthly consumption.
Battery runtime depends on usable watt-hours, not nameplate numbers alone. Voltage and amp-hours create nominal energy. Depth of discharge limits usable energy. That protects battery life. This calculator converts those inputs into realistic runtime. It helps you understand how long your inverter can support a connected load. That is useful for outages, night use, and backup planning.
Solar production changes with weather, heat, dust, and wiring losses. That is why derating is important. Peak sun hours also vary by location and season. By combining inverter demand with solar availability, this tool estimates the array size needed for daily recovery. It also suggests how many panels may be required based on panel wattage.
Inverter sizing is not only about continuous load. Start-up surge matters for motors, pumps, refrigerators, and tools. A safety margin adds protection against overloads and future expansion. The calculator shows both continuous and surge recommendations. That gives you a stronger basis for choosing an inverter that runs efficiently and safely.
Use this calculator before buying equipment. Use it when comparing battery upgrades. Use it when reviewing operating cost. Clear numbers reduce guesswork. Better sizing improves performance, reliability, and long-term value.
It shows how much input power becomes useful AC output. A 92% efficient inverter delivers 92% to the load and loses the rest as heat.
Standby power is used when the inverter stays on without carrying a full load. Over many hours, it can noticeably raise daily energy use.
It depends on battery chemistry and manufacturer guidance. Lower discharge generally supports longer battery life. Many systems use conservative limits for daily cycling.
Some devices draw extra power at start-up. Motors and compressors are common examples. Surge factor helps estimate the inverter size needed to handle that brief demand.
Peak sun hours describe average daily solar energy at a location. They simplify solar production estimates into equivalent full-power sunlight hours.
It accounts for real-world performance losses from heat, dust, cable losses, and mismatch. It keeps solar sizing more practical and realistic.
Yes. The calculator is useful for both. It helps estimate inverter demand, battery runtime, solar array size, and operating cost.
No. It is a planning tool. Final design should also consider site conditions, wiring, protection devices, local codes, and manufacturer limits.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.