Power Planner

Off-Grid Energy Sizing & Critical Load Analysis

Important Considerations

Inverter Surge Capability:

Ensure your inverter can handle the Peak Surge for at least 5-10 seconds. Induction motors (Fridges Pumps Power Tools AC Units) require 3-5x their running watts to start.

Note: Induction equipment (motors) can surge 5x-7x their rated power.

Battery Discharge Rate (C-Rating):

Verify your battery bank can deliver the required Instant Watts without voltage drop.

• Lead-Acid: 0.1C - 0.2C (Slow, prevents overheating)

• LiFePO4: 0.3C - 0.5C (Fast, high efficiency)

• C-Rating: Max current relative to capacity (100Ah @ 0.2C = 20A).

Equipment List

Device Name

Watts

Surge W

Hrs/Day

Duty Cycle

Qty

Device Name

Watts

Surge W

Hrs/Day

Duty Cycle

Qty

System Configuration

Battery Bank Voltage

Inverter Efficiency

Target Max Depth of Discharge (DoD)

Charger / Solar Output (Watts)

Daily Active Charge Hours

Expected Autonomy Days(Battery size is multiplied by this factor)

Power Results

System Load (incl. Inverter Losses)

150.0 Watts

INVERTER SURGE SCENARIOS:

Best Case (Single max surge)1200.0 W

Standard1200.0 W

Worst Case (Concurrent startup)1200.0 W

DAILY ENERGY BALANCE

Consumption (incl. losses):1397.6 Wh

Daily Energy Refill:+0.0 Wh

Net Balance:-1397.6 Wh

Sustainability Ratio:0.00x

Daily Net Balance:-1398 Wh

SYSTEM BALANCING (WHAT-IF)

Charger Output0W

Recharge Hours0h

Recalculating Equilibrium:

• To reach balance with current equipment, you need a charger of at least 0W.
• Or, increase your daily recharge window to 0.0 hours.

SYSTEM WARNINGS

❌

System in Deficit: You are losing 1398Wh daily. With your current battery size, the system will reach 0% in approximately 1.0 days. Increase charging power to avoid shutdown.

Required Battery Bank

232.9 Ah @ 12V

Battery Floor (Bridge the gap): 232.9 Ah

C-Rate Validations

Max Charge Rate:0.00C

Cont. Discharge:0.06C

Surge Capacity:0.51C

Note: Pure Sine Wave inverters are highly recommended. Many electronic devices and appliances may not function correctly or could even be damaged by Modified Sine Wave output.

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Determine your off-grid power requirements and battery bank needs for emergency scenarios. Correct sizing of inverters and discharge rates is critical for system reliability.

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