Peak Sun Hours in Coimbatore, Tamil Nadu, India
- Solar zone
- Zone 4 (excellent)
- Best month
- March (6.4)
- Worst month
- July (4.1)
- Climate
- Tropical · 24.6°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 5.51 | 6.01 | 5.24 | 1.96 | 22.8 | 67 |
| Feb | 6.20 | 6.67 | 5.63 | 2.04 | 25.1 | 56 |
| Mar | 6.39 | 7.07 | 5.04 | 2.33 | 27.7 | 53 |
| Apr | 6.11 | 7.17 | 3.95 | 2.59 | 28.4 | 63 |
| May | 5.58 | 7.06 | 3.17 | 2.65 | 26.6 | 76 |
| Jun | 4.55 | 7.02 | 1.69 | 2.62 | 24.5 | 83 |
| Jul | 4.14 | 6.95 | 1.13 | 2.56 | 23.8 | 85 |
| Aug | 4.36 | 7.05 | 1.48 | 2.57 | 23.7 | 85 |
| Sep | 4.97 | 7.00 | 2.52 | 2.53 | 23.9 | 85 |
| Oct | 4.72 | 6.42 | 2.55 | 2.37 | 23.8 | 85 |
| Nov | 4.62 | 5.92 | 3.16 | 2.15 | 22.8 | 84 |
| Dec | 4.88 | 5.72 | 4.29 | 1.97 | 22.0 | 79 |
GHI, Clear-sky, DNI, DHI in kWh/m²/day. Data: NASA POWER climatology (long-term monthly averages).
Off-grid calculator
Add appliances
- Add an appliance to size a system.
Sizing
- Daily load
- 0.00 kWh
- Panel wattage
- 0 W
- Panel count (400W modules)
- 0
- Battery bank
- 0.0 kWh
Sizing against worst-month PSH of 4.14 kWh/m²/day, 0.77 system efficiency.
About solar in Coimbatore
Coimbatore, India has a warm, tropical climate with a distinct wet and dry season. Its annual peak sun hours average 5.17 kWh/m²/day, a excellent solar resource by global standards.
The strongest month in Coimbatore is March (spring) at 6.39 kWh/m²/day, and the weakest is July (summer) at 4.14 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the July value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.
Coimbatore's solar conditions are well within the range where off-grid PV is a straightforward engineering exercise with standard-sized arrays and lithium batteries.
FAQ
- What are the peak sun hours in Coimbatore?
- Coimbatore averages 5.17 peak sun hours per day annually, ranging from 4.14 in July to 6.39 in March.
- How many solar panels do I need in Coimbatore?
- Panel count depends on your daily load. At Coimbatore's annual average of 5.17 kWh/m²/day, a 5 kWh/day load needs roughly 4 × 400 W panels. Use the calculator above for your actual load.
- What size battery do I need in Coimbatore?
- Sizing against Coimbatore's worst month (July, 4.14 kWh/m²/day) with 2 days of autonomy at 80% depth of discharge, a 5 kWh/day load needs about a 12.5 kWh battery bank.
- How does Coimbatore's solar resource compare globally?
- Coimbatore sits in solar zone 4 out of 5 (where 5 is strongest) at 5.17 kWh/m²/day — excellent by global standards. For reference, top-tier desert sites average ~6.5 and high-latitude cities around 2.5 kWh/m²/day.
- How does the wet season affect solar generation in Coimbatore?
- Coimbatore's dry-season output peaks at 6.39 kWh/m²/day in March; the wet season drops it to 4.14 in July. That ~44% swing is a key sizing consideration.
- Can solar panels survive tropical storms in Coimbatore?
- Most tier-1 PV panels are rated for 140+ mph wind loads; mounting hardware usually fails first. In cyclone-prone regions like India, specify IEC 61215-certified panels and anchor-bolt mounts rather than ballasted.
- What's the dry-to-wet output gap in Coimbatore?
- Coimbatore swings from 6.39 kWh/m²/day in March (dry) to 4.14 in July (wet) — roughly 44%. Year-round off-grid systems must size against the wet-season minimum.