How many solar panels you need for a 3BHK home in Noida depends on three things: your actual monthly electricity consumption, the wattage of panels chosen, and Noida's available peak sun hours (~5–5.5 hours/day). For most Noida 3BHK homes, a 3 kW to 5 kW system using 8–14 panels of 400–500W each covers the majority of daily needs.
Step 1: Find Your Monthly Consumption
Before picking a system size, pull out your last 12 electricity bills and note the monthly units consumed. This removes guesswork entirely. Typical Noida 3BHK consumption falls into three clear bands depending on AC usage:
| Usage Profile | Typical Appliances | Monthly Units (kWh) |
|---|---|---|
| Light usage (no AC) | LED lights, fans, fridge, TV, washing machine | 200–350 |
| Average usage (1 AC) | All above + 1 AC (5–6 hrs/day), geyser, microwave | 400–550 |
| Heavy usage (2–3 ACs) | All above + multiple ACs, EV charging, induction | 600–900 |
Step 2: Calculate Required System Size
The formula is straightforward: System size (kW) = Daily consumption (kWh) ÷ Peak sun hours ÷ System efficiency. For Noida, use 5.0–5.2 peak sun hours/day and 0.75–0.80 system efficiency to account for inverter and wiring losses. Here's how this plays out for each profile:
- Light usage (300 kWh/month → 10 kWh/day): 10 ÷ 5 ÷ 0.75 = ~2.7 kW → choose 3 kW system
- Average usage (450 kWh/month → 15 kWh/day): 15 ÷ 5 ÷ 0.75 = ~4 kW → choose 4–5 kW system
- Heavy usage (700 kWh/month → 23 kWh/day): 23 ÷ 5 ÷ 0.75 = ~6 kW → choose 6 kW system
Step 3: Convert kW to Panel Count
Modern residential panels in India come in 400W, 450W, and 500W ratings. Dividing your required system capacity by the individual panel wattage gives you the panel count:
| System Size | 400W Panels | 450W Panels | 500W Panels | Roof Space Needed |
|---|---|---|---|---|
| 3 kW | 8 panels | 7 panels | 6 panels | ~180–200 sq ft |
| 4 kW | 10 panels | 9 panels | 8 panels | ~240–260 sq ft |
| 5 kW | 13 panels | 12 panels | 10 panels | ~300–325 sq ft |
| 6 kW | 15 panels | 14 panels | 12 panels | ~360–400 sq ft |
The Most Common Choice for Noida 3BHK
A 3 kW system is ideal for families without AC or with minimal summer AC use, generating around 350–420 units/month in Noida's sunlight conditions and qualifying for the maximum ₹78,000 PM Surya Ghar subsidy. A 5 kW system is the most popular choice for families running 1–2 ACs, generating roughly 600–650 units/month and covering nearly the entire electricity bill.
The 5 kW system also qualifies for the enhanced subsidy bracket of up to ₹1,08,000 under PM Surya Ghar for systems above 3 kW.
Factors That Modify the Panel Count
Don't finalise panel count without checking these variables specific to your home:
- Shading from trees, water tanks, or neighbouring buildings: Even partial shading on 1–2 panels can cut system output by 20–30%; use micro-inverters or optimisers if shading is unavoidable.
- Roof orientation: South-facing panels give 100% output; east/west-facing roofs deliver 80–85% and may require 1–2 extra panels to compensate.
- Future load additions: Planning to buy an EV or add an AC in 2–3 years? Size the system 20–25% larger now—it's far cheaper than adding capacity later.
- Sanctioned load limit: Your DISCOM connection's sanctioned load caps the solar system size; systems must not exceed sanctioned load without load enhancement.
Estimated Cost After Subsidy (Noida, 2026)
| System Size | Approx Cost (Before Subsidy) | PM Surya Ghar Subsidy | Cost After Subsidy |
|---|---|---|---|
| 3 kW | ₹1.8–2.2 lakh | ₹78,000 | ₹1.0–1.4 lakh |
| 4 kW | ₹2.3–2.8 lakh | ₹78,000 | ₹1.5–2.0 lakh |
| 5 kW | ₹2.8–3.5 lakh | ₹1,08,000 | ₹1.7–2.4 lakh |
FAQs
Q1. How many solar panels does a typical 3BHK in Noida need?
Most Noida 3BHK homes need 8–14 panels of 400–500W depending on AC usage; a 1-AC household typically needs 10–12 panels in a 4–5 kW system.
Q2. What is the minimum roof area needed for a 3BHK solar system in Noida?
A 3 kW system needs approximately 180–200 sq ft of shadow-free flat roof area; a 5 kW system needs around 300–325 sq ft.
Q3. How many units will a 5 kW solar system generate in Noida per month?
In Noida's ~5 peak sun hours/day, a 5 kW system generates approximately 600–650 units/month on average across the year.
Q4. What subsidy is available for a 3BHK solar system in UP?
PM Surya Ghar provides ₹78,000 for up to 3 kW and up to ₹1,08,000 for systems above 3 kW, disbursed directly to your bank account after commissioning.
Q5. Should I go for 3 kW or 5 kW for my Noida 3BHK?
If you run 1+ AC units regularly and consume 400+ units/month, choose 5 kW. If consumption is below 350 units/month with no AC, 3 kW is sufficient and gets you full subsidy coverage.
