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Solar data for Vietnam

Across the 307 places in Vietnam the best fixed tilt for solar panels runs from 9° in Vĩnh Châu to 21° in Dien Bien Phu, and flat ground gets 3.6 to 5.5 peak sun hours a day. Every number is computed for each place.

Solar power in Vietnam at a glance

Averages over 307 places with climate data, for a fixed array facing south.

Best panel angle13°average, facing south
Peak sun hours4.47a day on flat ground
1 kWp makes1,320kWh a year at the best angle
Off-grid angle24°average, for the darkest month
Ho Chi Minh CityPhú Quý (most sun)
  • 3.61–3.98
  • 3.98–4.35
  • 4.35–4.71
  • 4.71–5.08
  • 5.08–5.45

Peak sun hours a day on flat ground. Each dot is one place.

The sunniest place in Vietnam is Phú Quý (Lam Dong) with 5.45 peak sun hours a day on flat ground; the least sunny are Thị Trấn Thất Khê and one other place with 3.61. A 1 kWp array at its best angle makes from 1,085 kWh a year in Thị Trấn Thất Khê to 1,591 kWh in Mui Ne — 1,320 kWh on average.

The best year-round tilt runs from 9° in Vĩnh Châu to 21° in Dien Bien Phu. Off-grid systems are sized for the darkest month and do better steeper, at 24° on average: at 70° that month brings 1.17 kWh per kWp a day in Tam Giang and 1.85 kWh in Hà Giang.

Size an off-grid system or open any place below for its sun path, monthly table and tilt curve.

Sunniest places in Vietnam

Ranked by peak sun hours on flat ground: the yearly average of a day's sunshine energy (NASA POWER climatology). Output: 1 kWp at its best year-round angle.

RankPlaceRegionSun hours/daykWh per kWp a yearBest tilt
1Phú QuýLam Dong5.451,5919°
2Mui NeLam Dong5.411,59111°
3La GiLam Dong5.401,58211°
4Ấp Bình ChâuHo Chi Minh City (HCMC)5.391,58011°
5Phan ThiếtLam Dong5.371,58111°
5Thị Trấn Phước BửuHo Chi Minh City (HCMC)5.371,57311°
7Thị Trấn Đất ĐỏHo Chi Minh City (HCMC)5.361,56811°
8Xã Long HảiHo Chi Minh City (HCMC)5.351,56511°
9Long DiềnHo Chi Minh City (HCMC)5.341,56411°
9Ấp Phước TĩnhHo Chi Minh City (HCMC)5.341,56211°

Least sunny places in Vietnam

RankPlaceRegionSun hours/daykWh per kWp a yearBest tilt
302Thị Trấn Na DươngLạng Sơn Province3.631,08917°
302Lạng SơnLạng Sơn Province3.631,08917°
305Cao BằngCao Bằng Province3.621,09317°
306Thị Trấn Trùng KhánhCao Bằng Province3.611,09318°
306Thị Trấn Thất KhêLạng Sơn Province3.611,08517°

Solar by region in Vietnam

Averages of the places in each region, sunniest first. Darkest month: what 1 kWp of off-grid panels at 70° makes a day in the worst month of the year.

RegionPlacesSun hours/daykWh per kWp a yearBest tiltDarkest month at 70°Sunniest place
Ho Chi Minh City (HCMC)285.281,54612°1.29 kWhẤp Bình Châu
Tay Ninh85.241,53412°1.31 kWhDương Minh Châu
Dong Nai85.231,53613°1.32 kWhLong Thành
Lam Dong115.201,53412°1.32 kWhPhú Quý
Vinh Long55.191,51410°1.24 kWhDuyên Hải
Khanh Hoa65.151,51210°1.32 kWhPhan Rang-Tháp Chàm
Dong Thap85.151,50411°1.29 kWhGò Công
Vietnam15.111,49111°1.28 kWhQuận Đức Thịnh
An Giang185.101,48911°1.27 kWhTân Châu
Can Tho City175.061,47510°1.24 kWhVĩnh Châu
Ca Mau135.031,46510°1.19 kWhTam Giang
Dak Lak84.921,45312°1.37 kWhTuy Hòa
Gia Lai54.891,44111°1.40 kWhQui Nhon
Quang Ngai64.831,42111°1.44 kWhLý Sơn
Da Nang City144.591,35111°1.49 kWhNúi Thành
Thừa Thiên Huế Province44.271,25811°1.53 kWhHương Thủy
Điện Biên Province24.251,31721°1.78 kWhDien Bien Phu
Quang Tri74.141,22112°1.57 kWhÐông Hà
Sơn La Province44.101,25820°1.79 kWhThị Trấn Thuận Châu
Lai Châu Province14.021,24421°1.75 kWhLai Châu
Hà Tĩnh Province44.011,18313°1.64 kWhKỳ Anh
Nghệ An Province83.991,18714°1.67 kWhThái Hòa
Thanh Hóa Province83.951,16714°1.77 kWhNghi Sơn
Ninh Binh33.891,15415°1.80 kWhNinh Bình
Hưng Yên Province53.841,14015°1.78 kWhThái Bình
Hai Phong63.831,13715°1.72 kWhCát Bà
Lao Cai43.801,15618°1.80 kWhLào Cai
Phu Tho63.801,13216°1.82 kWhHòa Bình
Hanoi573.791,12815°1.80 kWhXuân Mai
Quảng Ninh103.751,12116°1.68 kWhHạ Long
Bac Ninh73.741,11416°1.72 kWhThuận Thanh
Tuyen Quang43.701,11917°1.84 kWhHà Giang
Thai Nguyen53.701,10516°1.77 kWhPhổ Yên
Lạng Sơn Province33.621,08817°1.67 kWhThị Trấn Na Dương
Cao Bằng Province33.621,09517°1.81 kWhThị Trấn Nước Hai

Largest places in Vietnam at a glance

PlaceLatitudeBest tiltOff-grid tiltSun hours/day (flat)
Ho Chi Minh City10.8° N12°5°5.23
Hanoi21.0° N15°38°3.79
Haiphong20.9° N15°36°3.82
Cần Thơ10.0° N10°2°5.09
Huế16.5° N11°39°4.28
Da Nang16.1° N11°38°4.60
Biên Hòa10.9° N12°5°5.24
Thanh Hóa19.8° N14°38°3.96
Vinh18.7° N13°41°3.96
Thuận An10.9° N12°6°5.24
Nha Trang12.2° N10°32°5.10
Thủ Đức10.8° N12°5°5.24
Qui Nhon13.8° N10°37°4.98
Vũng Tàu10.3° N11°7°5.32
Dĩ An10.9° N12°5°5.24
Rạch Giá10.0° N11°1°5.06
Bắc Giang21.3° N16°37°3.72
Nam Định20.4° N15°38°3.90
Buôn Ma Thuột12.7° N13°15°4.91
Thái Nguyên21.6° N16°37°3.70

Daylight and clock time in Vietnam

In Thị Trấn Trùng Khánh (22.8° N), the northernmost place, the longest day of the year lasts 13 h 32 min and the shortest 10 h 44 min; in Năm Căn (8.8° N), the southernmost, 12 h 38 min and 11 h 37 min. Vietnam does not use daylight saving time: the clocks stay the same all year.

Time zonePlacesUTC offsetClocks change in 2026
Asia/Ho_Chi_Minh193UTC+7no daylight saving time
Asia/Bangkok114UTC+7no daylight saving time

Questions about solar in Vietnam

What is the best angle for solar panels in Vietnam?
Facing south, between 9° and 21° depending on the place — 13° on average over 307 places. Off-grid systems that must get through the darkest month do better steeper, at about 24° on average.
How many peak sun hours does Vietnam get?
From 3.6 hours a day in Thị Trấn Thất Khê to 5.5 in Phú Quý on flat ground, averaged over the year; 4.5 on average.
How much electricity does 1 kWp of solar panels produce in Vietnam?
About 1,320 kWh a year at the best fixed angle on average, from 1,085 kWh in Thị Trấn Thất Khê to 1,591 kWh in Mui Ne. These are long-term climate averages; a single year can be several per cent higher or lower.
Where is the sunniest place in Vietnam?
Phú Quý (Lam Dong) gets the most sun of the 307 places: 5.45 peak sun hours a day on flat ground, so 1 kWp there makes about 1,591 kWh a year.
Does Vietnam use daylight saving time?
Vietnam does not use daylight saving time: the clocks stay the same all year.
How long is the longest day in Vietnam?
13 h 32 min in Thị Trấn Trùng Khánh; the shortest day lasts 10 h 44 min in Thị Trấn Trùng Khánh.

All places in Vietnam

Lai Châu Province

Điện Biên Province