Peak Sun Hours in Gebze, Kocaeli, Turkey
- Solar zone
- Zone 3 (good)
- Best month
- July (7.3)
- Worst month
- December (1.5)
- Climate
- Temperate · 14.8°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 1.64 | 2.79 | 2.28 | 0.84 | 5.8 | 83 |
| Feb | 2.37 | 3.87 | 2.63 | 1.20 | 6.5 | 81 |
| Mar | 3.55 | 5.35 | 3.41 | 1.64 | 8.5 | 78 |
| Apr | 4.95 | 6.81 | 4.28 | 2.15 | 11.8 | 76 |
| May | 6.12 | 7.82 | 5.17 | 2.50 | 16.9 | 76 |
| Jun | 7.03 | 8.25 | 6.60 | 2.37 | 21.6 | 73 |
| Jul | 7.27 | 8.03 | 7.53 | 2.11 | 24.3 | 70 |
| Aug | 6.39 | 7.09 | 6.84 | 1.91 | 24.7 | 71 |
| Sep | 4.76 | 5.77 | 5.31 | 1.66 | 21.3 | 72 |
| Oct | 3.16 | 4.26 | 4.00 | 1.27 | 16.6 | 78 |
| Nov | 2.15 | 3.03 | 3.34 | 0.91 | 12.0 | 80 |
| Dec | 1.51 | 2.45 | 2.44 | 0.73 | 7.8 | 82 |
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 1.51 kWh/m²/day, 0.77 system efficiency.
About solar in Gebze
Gebze, Turkey has a temperate climate with meaningful seasonal variation in solar resource. Its annual peak sun hours average 4.24 kWh/m²/day, a good solar resource by global standards.
The strongest month in Gebze is July (summer) at 7.27 kWh/m²/day, and the weakest is December (winter) at 1.51 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the December value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.
Gebze'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 Gebze?
- Gebze averages 4.24 peak sun hours per day annually, ranging from 1.51 in December to 7.27 in July.
- How many solar panels do I need in Gebze?
- Panel count depends on your daily load. At Gebze's annual average of 4.24 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 Gebze?
- Sizing against Gebze's worst month (December, 1.51 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 Gebze's solar resource compare globally?
- Gebze sits in solar zone 3 out of 5 (where 5 is strongest) at 4.24 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 much does winter reduce solar output in Gebze?
- Gebze's worst month (December) delivers 1.51 kWh/m²/day — about 21% of the summer peak of 7.27. Off-grid systems here typically oversize 1.5–2× or pair with a backup source.
- Do cloudy days significantly affect Gebze's solar?
- Partly. Diffuse light still produces 10–25% of clear-sky output. Gebze's 4.24 kWh/m²/day already reflects average cloudiness, so no further derating is needed for sizing.
- What panel tilt works best in Gebze?
- At Gebze's latitude (41°), a fixed tilt near 41° balances year-round yield. Winter-heavy loads favor latitude + 15°; summer-heavy, latitude − 15°.