Solar panels: how many does your home need?
Panel watts × sun hours = daily energy (a 540 W panel × ~4.5 h ≈ 2.4 units/day) and how to size panels from your monthly units.
How many solar panels does YOUR home need? Easy maths ☀️🏠
1️⃣ ONE PANEL, ONE DAY: a 540 W panel only gives 540 W in strong noon sun. Across a whole day, India gets about 4.5 "full-sun hours" (it varies by city and season). 540 W × 4.5 h = 2430 Wh ≈ 2.4 units. After dust, heat and inverter losses: about 2 units a day per panel.
2️⃣ YOUR BILL: 300 units a month ÷ 30 days = 10 units a day. 10 ÷ 2 = 5 panels → 5 × 540 W ≈ 2.7 kW system (about 13 m² of roof).
3️⃣ WIRING: the panels are wired in SERIES, like battery cells, so the volts add: 5 × 41 V ≈ 205 V DC into the inverter, while the current stays about 13 A. The inverter turns it into 230 V AC.
📌 Quick rule: number of panels ≈ your daily units ÷ 2. (Get a proper site survey before you buy.)
Read the voiceover (transcript)
- How many solar panels does your home need?
- One five-forty watt panel: four and a half sun hours. After losses, about two units a day!
- Your bill says three hundred units a month: ten a day. Ten divided by two: five panels, about two point seven kilowatts!
- Wire them in series: the volts add up to two hundred and five!
- Daily units divided by two: your panels!
- Next: net metering! Follow for part nine!
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