Peak Sun Hours in Phu Quoc, An Giang, Vietnam
- Solar zone
- Zone 3 (good)
- Best month
- March (5.9)
- Worst month
- September (4.2)
- Climate
- Tropical · 28.1°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 5.13 | 5.82 | 4.49 | 2.08 | 27.0 | 75 |
| Feb | 5.70 | 6.29 | 4.64 | 2.27 | 27.3 | 75 |
| Mar | 5.90 | 6.69 | 4.18 | 2.49 | 28.1 | 77 |
| Apr | 5.76 | 6.91 | 3.73 | 2.60 | 29.1 | 77 |
| May | 4.99 | 7.03 | 2.79 | 2.52 | 29.3 | 80 |
| Jun | 4.48 | 6.95 | 2.31 | 2.37 | 28.8 | 82 |
| Jul | 4.24 | 6.97 | 1.94 | 2.31 | 28.4 | 82 |
| Aug | 4.26 | 7.04 | 1.92 | 2.35 | 28.2 | 83 |
| Sep | 4.20 | 6.90 | 1.89 | 2.32 | 28.0 | 83 |
| Oct | 4.73 | 6.48 | 2.81 | 2.35 | 27.9 | 82 |
| Nov | 4.98 | 6.00 | 4.01 | 2.20 | 27.9 | 80 |
| Dec | 4.96 | 5.70 | 4.63 | 2.00 | 27.4 | 77 |
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 4.20 kWh/m²/day, 0.77 system efficiency.
About solar in Phu Quoc
Phu Quoc, Vietnam has a warm, tropical climate with a distinct wet and dry season. Its annual peak sun hours average 4.94 kWh/m²/day, a good solar resource by global standards.
The strongest month in Phu Quoc is March (spring) at 5.9 kWh/m²/day, and the weakest is September (autumn) at 4.2 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the September value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.
Phu Quoc'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 Phu Quoc?
- Phu Quoc averages 4.94 peak sun hours per day annually, ranging from 4.2 in September to 5.9 in March.
- How many solar panels do I need in Phu Quoc?
- Panel count depends on your daily load. At Phu Quoc's annual average of 4.94 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 Phu Quoc?
- Sizing against Phu Quoc's worst month (September, 4.2 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 Phu Quoc's solar resource compare globally?
- Phu Quoc sits in solar zone 3 out of 5 (where 5 is strongest) at 4.94 kWh/m²/day — good 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 Phu Quoc?
- Phu Quoc's dry-season output peaks at 5.9 kWh/m²/day in March; the wet season drops it to 4.2 in September. That ~34% swing is a key sizing consideration.
- Can solar panels survive tropical storms in Phu Quoc?
- Most tier-1 PV panels are rated for 140+ mph wind loads; mounting hardware usually fails first. In cyclone-prone regions like Vietnam, specify IEC 61215-certified panels and anchor-bolt mounts rather than ballasted.
- What's the dry-to-wet output gap in Phu Quoc?
- Phu Quoc swings from 5.9 kWh/m²/day in March (dry) to 4.2 in September (wet) — roughly 34%. Year-round off-grid systems must size against the wet-season minimum.