How to Size Your Rooftop Solar System Using Your APDCL Bill
Determining the correct solar system capacity (kW) is essential to avoid under-sizing (which leaves you with remaining grid bills) or over-sizing (which incurs unnecessary initial cost). In Assam, system sizing is directly derived from your average monthly energy consumption in units (kWh) recorded on your APDCL bill.
APDCL Bill Sizing & Subsidy Quick Reference Table
| Average Monthly APDCL Bill | Monthly Unit Consumption | Recommended Solar System Size | Total Government Subsidy | Net Payable After Subsidy |
|---|---|---|---|---|
| ₹1,200 – ₹2,200 | 150 – 250 Units | 2kW Solar System | ₹1,05,000 (Combined) | Approx. ₹45,000 |
| ₹2,300 – ₹4,000 | 260 – 450 Units | 3kW Solar System | ₹1,30,800 (Max Subsidy) | ₹59,200 |
| ₹4,200 – ₹7,000 | 460 – 750 Units | 5kW Solar System | ₹1,30,800 (Capped) | Approx. ₹1,94,200 |
| ₹8,000 – ₹15,000+ | 800 – 1,500+ Units | 10kW Solar System | ₹1,30,800 (Capped) | Custom Quote |
Appliance Wattage Calculation Method
Alternatively, calculate your peak daytime load requirements using typical household appliance wattage ratings:
- 1.5 Ton Inverter Air Conditioner: 1,400W – 1,600W
- Refrigerator (Double Door): 250W – 350W
- Water Submersible Pump (1 HP): 750W
- LED Lights & Ceiling Fans (Whole House): 300W – 500W
- Total Simultaneous Load for 3kW System: Runs 1 AC + Refrigerator + Water Pump + Lights/Fans smoothly during daylight hours.
Next Step: Get a Free Site Survey
Send your APDCL bill copy and rooftop photos to Solar Assam via WhatsApp for a tailored quote and subsidy eligibility check.