Dhangadhi, Sudurpashchim Pradesh, Nepal shows strong potential for year-round solar energy generation, though with notable seasonal variations that make it a moderately favorable location for solar PV installations.

Seasonal Solar Performance

The location experiences significant seasonal fluctuations in solar energy output. Spring emerges as the peak season, delivering an impressive 6.57kWh per day per kW of installed solar capacity. Summer follows as the second-best performing season at 5.02kWh/day, while autumn maintains decent production at 4.71kWh/day. Winter presents the most challenging period for solar generation, dropping to 3.53kWh/day per kW. Despite this seasonal low, the winter output remains sufficient to justify year-round solar installations, particularly when considering the excellent spring and summer performance that helps balance the annual energy budget.

Optimal Installation Configuration

For maximum year-round energy production at Dhangadhi, Sudurpashchim Pradesh, solar panels should be installed at a fixed tilt angle of 26 degrees facing south. This optimal angle is calculated by analyzing daily solar elevation angles throughout the year, weighted by solar irradiance data to maximize total annual output.

Local Environmental Challenges

Several environmental and weather factors in the Dhangadhi region can significantly impact solar panel performance:

• Monsoon season dust and debris: The pre-monsoon and post-monsoon periods bring substantial dust accumulation on panel surfaces
• Heavy monsoon rainfall: While rain can clean panels, intense monsoon downpours may cause temporary shading from cloud cover
• Agricultural burning: Seasonal crop burning in surrounding areas creates smoke and particulate matter that reduces solar irradiance
• High humidity levels: Elevated moisture can lead to faster degradation of electrical components

Preventative Measures for Enhanced Performance

To maximize solar energy production despite these challenges, several installation strategies prove effective. Regular cleaning schedules become essential, particularly before and after monsoon seasons, with monthly cleaning recommended during peak dust periods. Installing panels with adequate spacing allows for better air circulation, reducing humidity-related issues and preventing overheating. Choosing high-quality, weather-resistant mounting systems and electrical components specifically rated for tropical conditions helps ensure longevity. Implementing tilt-adjustable mounting systems, while more expensive, can optimize seasonal performance by allowing steeper angles during winter months to capture more available sunlight. Additionally, installing monitoring systems enables quick identification of performance drops due to environmental factors, allowing for prompt maintenance responses. The location's overall solar potential remains quite good despite these challenges, making Dhangadhi a viable location for solar PV installations when proper planning and maintenance protocols are implemented.

Note: The Northern Sub Tropics extend from 23.5° latitude North up to 35° latitude.

So far, we have conducted calculations to evaluate the solar photovoltaic (PV) potential in 40 locations across Nepal. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Nepal by location

Solar output per kW of installed solar PV by season in Dhangadhi

Seasonal solar PV output for Latitude: 28.6997, Longitude: 80.5862 (Dhangadhi, Nepal), 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 26° South in Dhangadhi, Nepal

To maximize your solar PV system's energy output in Dhangadhi, Nepal (Lat/Long 28.6997, 80.5862) throughout the year, you should tilt your panels at an angle of 26° 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 Dhangadhi, Nepal

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 Dhangadhi, Nepal. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 26° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
12° South in Summer	34° South in Autumn	43° South in Winter	22° 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 Dhangadhi, Nepal

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 Dhangadhi, Nepal.

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 Dhangadhi, Nepal

Topographical Features of Dhangadhi

Dhangadhi sits in the far-western region of Nepal within the Terai plains, a flat lowland area that extends along Nepal's southern border with India. This city is positioned at a relatively low elevation of approximately 200 meters above sea level, making it part of the characteristic flat terrain that defines much of southern Nepal. The landscape around Dhangadhi is predominantly agricultural, with vast expanses of fertile farmland stretching in all directions across the plains. The topography is remarkably uniform and gentle, with minimal elevation changes across large areas. This flat terrain is punctuated by numerous rivers and streams that flow southward from the higher elevations of the Chure Hills to the north. The Mahakali River forms a significant geographical feature to the west, serving as the border between Nepal and India. Smaller waterways meander through the agricultural landscape, creating a network of drainage channels that support the region's farming activities.

Terrain Challenges and Opportunities

The Terai plains experience seasonal flooding during monsoon periods, which shapes both the natural landscape and human settlement patterns. This flooding creates temporary wetlands and affects the suitability of certain areas for permanent installations. However, the generally flat nature of the terrain means that drainage patterns are predictable, and higher ground can be identified for development purposes. North of Dhangadhi, the landscape gradually transitions toward the Chure Hills, also known as the Siwalik Range. These low hills create a gentle rise in elevation and represent the first foothill zone before the more dramatic Himalayan ranges further north. The Chure Hills are characterized by relatively modest elevations and rolling terrain, offering different topographical conditions compared to the completely flat plains.

Optimal Areas for Large-Scale Solar Development

The most suitable areas for large-scale solar photovoltaic installations around Dhangadhi would be the elevated sections of agricultural land that remain above seasonal flood levels. These areas combine the advantages of flat terrain for easy installation and maintenance while avoiding the complications of monsoon flooding. The extensive agricultural plains offer numerous potential sites where large solar arrays could be established without significant grading or terrain modification. The transitional zone between the flat Terai plains and the beginning slopes of the Chure Hills presents particularly attractive opportunities. This area typically features gentle slopes and elevated positions that provide natural drainage while maintaining relatively easy access for construction and maintenance activities. The terrain in this zone is stable and well-drained, making it ideal for permanent solar installations. Areas to the east and west of Dhangadhi city center, where the agricultural land extends across broad flat expanses, would also be highly suitable for solar development. These locations benefit from the characteristic openness of the Terai landscape, which minimizes shading concerns from topographical features. The uniform terrain allows for optimal panel orientation and spacing across large areas. The slightly elevated agricultural terraces and farmland that sit above the immediate floodplain represent another category of prime solar development sites. These areas maintain the flat characteristics ideal for solar installations while providing the elevation necessary to avoid seasonal water issues that could affect equipment and access roads.

Nepal solar PV Stats as a country

Nepal ranks 89th in the world for cumulative solar PV capacity, with 93 total MW's of solar PV installed. This means that 0.10% of Nepal's total energy as a country comes from solar PV (that's 43rd in the world). Each year Nepal is generating 3 Watts from solar PV per capita (Nepal ranks 86th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Nepal?

Yes, there are incentives for businesses wanting to install solar energy in Nepal. The Government of Nepal has implemented a number of policies and programs to promote the use of renewable energy sources such as solar power. These include tax exemptions, subsidies, and other financial incentives for businesses that install solar systems. Additionally, the government has established a Renewable Energy Fund which provides grants to support research and development activities related to renewable energy technologies.

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

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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.