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Peak Sun Hours in Guangzhou, Guangdong, China

3.8
kWh/m²/day (annual avg)
Solar zone
Zone 2 (moderate)
Best month
July (5.0)
Worst month
February (2.8)
Climate
Tropical · 22.6°C

Monthly solar breakdown

J: 2.83 kWh/m²/day F: 2.8 kWh/m²/day M: 2.86 kWh/m²/day A: 3.28 kWh/m²/day M: 3.95 kWh/m²/day J: 4.17 kWh/m²/day J: 5 kWh/m²/day A: 4.87 kWh/m²/day S: 4.59 kWh/m²/day O: 4.22 kWh/m²/day N: 3.48 kWh/m²/day D: 3.09 kWh/m²/day J F M A M J J A S O N D 6 0
Month GHI Clear-sky DNI DHI Temp °C Humid %
Jan 2.83 4.36 2.43 1.44 14.0 70
Feb 2.80 5.00 1.69 1.65 16.9 73
Mar 2.86 5.49 1.19 1.80 20.1 74
Apr 3.28 6.13 1.12 2.12 23.8 78
May 3.95 6.92 1.55 2.42 26.5 83
Jun 4.17 7.15 1.72 2.56 27.8 88
Jul 5.00 7.27 2.79 2.69 28.3 87
Aug 4.87 6.81 2.67 2.60 28.3 86
Sep 4.59 6.15 2.86 2.32 26.9 84
Oct 4.22 5.30 3.32 1.93 23.7 77
Nov 3.48 4.59 3.36 1.50 19.9 73
Dec 3.09 4.14 3.32 1.33 14.8 67

GHI, Clear-sky, DNI, DHI in kWh/m²/day. Data: NASA POWER climatology (long-term monthly averages).

Off-grid calculator

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Sizing against worst-month PSH of 2.80 kWh/m²/day, 0.77 system efficiency.

About solar in Guangzhou

Guangzhou, China has a warm, tropical climate with a distinct wet and dry season. Its annual peak sun hours average 3.76 kWh/m²/day, a moderate solar resource by global standards.

The strongest month in Guangzhou is July (summer) at 5 kWh/m²/day, and the weakest is February (winter) at 2.8 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the February value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.

Given the moderate resource, Guangzhou installations typically oversize panels or combine solar with another source (grid, generator, hydro) for reliability.

FAQ

What are the peak sun hours in Guangzhou?
Guangzhou averages 3.76 peak sun hours per day annually, ranging from 2.8 in February to 5 in July.
How many solar panels do I need in Guangzhou?
Panel count depends on your daily load. At Guangzhou's annual average of 3.76 kWh/m²/day, a 5 kWh/day load needs roughly 5 × 400 W panels. Use the calculator above for your actual load.
What size battery do I need in Guangzhou?
Sizing against Guangzhou's worst month (February, 2.8 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 Guangzhou's solar resource compare globally?
Guangzhou sits in solar zone 2 out of 5 (where 5 is strongest) at 3.76 kWh/m²/day — moderate 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 Guangzhou?
Guangzhou's dry-season output peaks at 5 kWh/m²/day in July; the wet season drops it to 2.8 in February. That ~59% swing is a key sizing consideration.
Can solar panels survive tropical storms in Guangzhou?
Most tier-1 PV panels are rated for 140+ mph wind loads; mounting hardware usually fails first. In cyclone-prone regions like China, specify IEC 61215-certified panels and anchor-bolt mounts rather than ballasted.
What's the dry-to-wet output gap in Guangzhou?
Guangzhou swings from 5 kWh/m²/day in July (dry) to 2.8 in February (wet) — roughly 59%. Year-round off-grid systems must size against the wet-season minimum.