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Peak Sun Hours in Surat, Gujarat, India

5.4
kWh/m²/day (annual avg)
Solar zone
Zone 4 (excellent)
Best month
May (7.3)
Worst month
August (4.2)
Climate
Tropical · 27.3°C

Monthly solar breakdown

J: 4.7 kWh/m²/day F: 5.61 kWh/m²/day M: 6.53 kWh/m²/day A: 7.17 kWh/m²/day M: 7.3 kWh/m²/day J: 5.73 kWh/m²/day J: 4.3 kWh/m²/day A: 4.23 kWh/m²/day S: 4.95 kWh/m²/day O: 5.36 kWh/m²/day N: 4.68 kWh/m²/day D: 4.35 kWh/m²/day J F M A M J J A S O N D 9 0
Month GHI Clear-sky DNI DHI Temp °C Humid %
Jan 4.70 4.83 5.57 1.48 22.9 36
Feb 5.61 5.73 6.18 1.64 25.2 37
Mar 6.53 6.70 6.48 1.92 28.6 39
Apr 7.17 7.33 6.65 2.10 31.5 48
May 7.30 7.51 6.30 2.32 32.3 56
Jun 5.73 7.03 3.20 2.85 29.9 74
Jul 4.30 6.67 1.32 2.76 27.4 87
Aug 4.23 6.54 1.39 2.70 26.6 89
Sep 4.95 6.15 2.92 2.48 26.9 86
Oct 5.36 5.63 4.96 1.89 26.8 70
Nov 4.68 4.85 5.05 1.58 25.5 55
Dec 4.35 4.51 5.31 1.39 23.8 42

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

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Panel count (400W modules)
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Sizing against worst-month PSH of 4.23 kWh/m²/day, 0.77 system efficiency.

About solar in Surat

Surat, India has a warm, tropical climate with a distinct wet and dry season. Its annual peak sun hours average 5.41 kWh/m²/day, a excellent solar resource by global standards.

The strongest month in Surat is May (spring) at 7.3 kWh/m²/day, and the weakest is August (summer) at 4.23 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the August value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.

Surat'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 Surat?
Surat averages 5.41 peak sun hours per day annually, ranging from 4.23 in August to 7.3 in May.
How many solar panels do I need in Surat?
Panel count depends on your daily load. At Surat's annual average of 5.41 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 Surat?
Sizing against Surat's worst month (August, 4.23 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 Surat's solar resource compare globally?
Surat sits in solar zone 4 out of 5 (where 5 is strongest) at 5.41 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 Surat?
Surat's dry-season output peaks at 7.3 kWh/m²/day in May; the wet season drops it to 4.23 in August. That ~57% swing is a key sizing consideration.
Can solar panels survive tropical storms in Surat?
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 Surat?
Surat swings from 7.3 kWh/m²/day in May (dry) to 4.23 in August (wet) — roughly 57%. Year-round off-grid systems must size against the wet-season minimum.