Solar Energy Potential in Lang Son, Lạng Sơn Province, Vietnam

Lang Son, Lạng Sơn Province, Vietnam, located at 21.8508° N, 106.7592° E, offers moderate potential for solar energy generation throughout the year. This tropical location experiences seasonal variations in solar productivity that align with its wet and dry seasons rather than extreme temperature differences. The solar energy production varies significantly across seasons. Summer stands out as the most productive period with 5.56 kWh per day for each kilowatt of installed solar capacity. This drops to 3.96 kWh/day in autumn, reaches its lowest point in winter at 3.19 kWh/day, and recovers somewhat in spring to 3.61 kWh/day. For fixed solar panel installations in Lang Son, Lạng Sơn Province, the optimal tilt angle is 19 degrees facing South. This specific angle has been calculated to maximize year-round energy production by accounting for the location's latitude and the varying solar irradiance throughout the year.

Environmental and Weather Factors

Several significant factors can impact solar energy production in Lang Son:

• Monsoon rainfall: The region experiences heavy monsoon rains that can reduce solar output during the wet season (May to October). Panels should be installed with proper drainage systems and at the optimal angle to allow water runoff.
• High humidity: Lang Son's tropical humidity can cause dust to stick to panels more readily, reducing efficiency. Regular cleaning schedules are essential for maintaining optimal performance.
• Seasonal cloud cover: The monsoon season brings extended periods of cloud cover that significantly impact production. Sizing systems appropriately to account for this seasonal variation is crucial.
• Typhoon risk: The region is susceptible to typhoons that can damage installations. Using reinforced mounting systems and high-wind-rated panels is recommended.

To mitigate these challenges, solar installations should incorporate robust mounting structures, regular maintenance schedules, and possibly hybrid systems that can compensate during the less productive winter months. Microinverters or power optimizers can also help manage partial shading issues that might occur during cloudy periods. Despite these challenges, Lang Son's location still provides sufficient solar resources to make photovoltaic systems viable, especially during the summer months when production peaks.

Note: The Tropics are located between 23.5° North and -23.5° South of the equator.

So far, we have conducted calculations to evaluate the solar photovoltaic (PV) potential in 160 locations across Vietnam. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Vietnam by location

Solar output per kW of installed solar PV by season in Lang Son

Seasonal solar PV output for Latitude: 21.8508, Longitude: 106.7592 (Lang Son, Vietnam), based on our analysis of 8760 hourly intervals of solar and meteorological data (one whole year) retrieved for that set of coordinates/location from NASA POWER (The Prediction of Worldwide Energy Resources) API:

 

Ideally tilt fixed solar panels 19° South in Lang Son, Vietnam

To maximize your solar PV system's energy output in Lang Son, Vietnam (Lat/Long 21.8508, 106.7592) throughout the year, you should tilt your panels at an angle of 19° South for fixed panel installations.

As the Earth revolves around the Sun each year, the maximum angle of elevation of the Sun varies by +/- 23.45 degrees from its equinox elevation angle for a particular latitude. Finding the exact optimal angle to maximise solar PV production throughout the year can be challenging, but with careful consideration of historical solar energy and meteorological data for a certain location, it can be done precisely.

We use our own calculation, which incorporates NASA solar and meteorological data for the exact Lat/Long coordinates, to determine the ideal tilt angle of a solar panel that will yield maximum annual solar output. We calculate the optimal angle for each day of the year, taking into account its contribution to the yearly total PV potential at that specific location.

Seasonally adjusted solar panel tilt angles for Lang Son, Vietnam

If you can adjust the tilt angle of your solar PV panels, please refer to the seasonal tilt angles below for optimal solar energy production in Lang Son, Vietnam. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 19° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
6° South in Summer	27° South in Autumn	38° South in Winter	13° South in Spring

Our recommendations take into account more than just latitude and Earth's position in its elliptical orbit around the Sun. We also incorporate historical solar and meteorological data from NASA's Prediction of Worldwide Energy Resources (POWER) API to assign a weight to each ideal angle for each day based on its historical contribution to overall solar PV potential during a specific season.

This approach allows us to provide much more accurate recommendations than relying solely on latitude, as it considers unique weather conditions in different locations sharing the same latitude worldwide.

Calculate solar panel row spacing in Lang Son, Vietnam

We've added a feature to calculate minimum solar panel row spacing by location. Enter your panel size and orientation below to get the minimum spacing in Lang Son, Vietnam.

Our calculation method

1. Solar Position:
   We determine the Sun's position on the Winter solstice using the location's latitude and solar declination.
2. Shadow Projection:
   We calculate the shadow length cast by panels using trigonometry, considering panel tilt and the Sun's elevation angle.
3. Minimum Spacing:
   We add the shadow length to the horizontal space occupied by tilted panels.

This approach ensures maximum space efficiency while avoiding shading during critical times, as the Winter solstice represents the worst-case scenario for shadow length.

Topography for solar PV around Lang Son, Vietnam

The topography around Lang Son, Vietnam presents a diverse landscape characterized predominantly by rugged, karst-dominated terrain. Located in the northeastern part of Vietnam near the Chinese border, Lang Son sits within a region of limestone mountains and hills that create a dramatic, undulating landscape. The city itself rests in a valley at approximately 250-300 meters above sea level, surrounded by peaks that can reach 500-700 meters in elevation.

Karst Landscape Features

The distinctive karst formations around Lang Son include numerous limestone hills with steep sides, caves, sinkholes, and underground streams. These geological features create a picturesque scenery but also present challenges for large-scale development projects. The terrain is irregular, with scattered flat valleys between the limestone outcrops where agricultural activities and settlements concentrate. The Ky Cung River flows through Lang Son province, creating fertile valleys amid the mountainous terrain. These valleys offer some of the few relatively flat areas in the region, though they are typically narrow and limited in extent.

Border Highlands

Moving toward the Chinese border to the north and northeast, the landscape becomes increasingly mountainous, with higher elevations and steeper slopes. These highlands form part of the larger mountain system that stretches across northern Vietnam and southern China. Dense forests still cover many of these mountain slopes, though deforestation has affected some areas. To the south and southwest of Lang Son city, the terrain gradually transitions to less rugged hills as it merges with the Red River Delta region, though still maintaining significant relief compared to the flat delta plains further south.

Solar PV Potential Areas

For large-scale solar photovoltaic installations, several areas near Lang Son offer more favorable conditions than others: The broader valleys along the Ky Cung River and its tributaries present the most immediately suitable terrain for solar development. These areas provide relatively flat land with good solar exposure, though they face competition from agricultural uses as they represent some of the most productive farmland in the region. South-facing hillsides with moderate slopes (under 15-20 degrees) could be utilized for solar installations with appropriate engineering solutions. These locations benefit from excellent sun exposure while requiring less valuable agricultural land. The transitional areas toward the southwest of Lang Son province, where the landscape becomes less rugged, offer promising locations for large-scale solar development. These gently rolling hills provide sufficient flat or moderately sloped land while generally having good solar exposure.

Topographical Challenges

Despite these potential areas, the karst topography presents significant challenges for large-scale solar development. The irregular terrain means that many sites would require substantial earthworks and custom mounting solutions, increasing installation costs. Additionally, the region experiences seasonal fog and cloud cover, particularly during winter months, which can reduce solar generation efficiency. The limited availability of large, contiguous flat areas means that solar installations might need to be distributed across multiple smaller sites rather than concentrated in one massive facility. This distributed approach could actually provide benefits in terms of grid integration and resilience but would increase infrastructure and maintenance complexity.

Infrastructure Considerations

The mountainous terrain also affects infrastructure development necessary for solar projects. Road access to potential sites can be challenging, potentially increasing construction and maintenance costs. However, Lang Son's proximity to China and its position along major transportation corridors does provide some logistical advantages for equipment delivery. Transmission infrastructure would need careful planning given the topographical constraints, though the existing electrical grid serving the provincial capital provides a foundation that could be expanded to accommodate new generation capacity.

Vietnam solar PV Stats as a country

Vietnam ranks 9th in the world for cumulative solar PV capacity, with 16,660 total MW's of solar PV installed. Each year Vietnam is generating 171 Watts from solar PV per capita (Vietnam ranks 30th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Vietnam?

Yes, there are several incentives for businesses wanting to install solar energy in Vietnam. The government has implemented a number of policies and programs to encourage the development of renewable energy sources, including solar energy. These include tax exemptions, preferential loans, and feed-in tariffs for electricity generated from solar power plants. Additionally, the government has established a Renewable Energy Development Fund to provide financial support for projects related to renewable energy sources such as solar power.

Do you have more up to date information than this on incentives towards solar PV projects in Vietnam? Please reach out to us and help us keep this information current. Thanks!

Citation Guide

Article Details for Citation

Tell Us About Your Work

We love seeing how our research helps others! If you've cited this article in your work, we'd be delighted to hear about it. Drop us a line via our Contact Us page or on X, to share where you've used our information - we may feature a link to your work on our site. This helps create a network of valuable resources for others in the solar energy community and helps us understand how our research is contributing to the field. Plus, we occasionally highlight exceptional works that reference our research on our social media channels.

Feeling generous?

Share this with your friends!

Compare this location to others worldwide for solar PV potential

The solar PV analyses available on our website, including this one, are offered as a free service to the global community. Our aim is to provide education and aid informed decision-making regarding solar PV installations.

However, please note that these analyses are general guidance and may not meet specific project requirements. For in-depth, tailored forecasts and analysis crucial for feasibility studies or when pursuing maximum ROI from your solar projects, feel free to contact us; we offer comprehensive consulting services expressly for this purpose.

Helping you assess viability of solar PV for your site

Calculate Your Optimal Solar Panel Tilt Angle: A Comprehensive Guide

Enhance your solar panel's performance with our in-depth guide. Determine the best tilt angle using hard data, debunk common misunderstandings, and gain insight into how your specific location affects solar energy production.