Janakpur Dham, Madhesh, Nepal represents a moderately good location for solar energy generation, positioned in the Northern Sub Tropics at coordinates 26.728°N, 85.9285°E. The location shows decent solar potential throughout most of the year, though with notable seasonal variations that affect energy production.

Seasonal Solar Performance

The solar energy output at Janakpur Dham varies significantly across the seasons. Spring emerges as the most productive period, delivering 5.91 kWh per day for each kilowatt of installed solar capacity. This makes it the ideal time for maximum energy generation at this location. Summer and autumn maintain relatively consistent performance levels, producing 4.66 kWh/day and 4.56 kWh/day respectively. However, winter presents a considerable challenge, dropping to just 3.55 kWh/day per kilowatt installed. This represents a 40% decrease compared to the peak spring output. For optimal year-round performance at Janakpur Dham, Madhesh, solar panels should be installed at a fixed tilt angle of 25 degrees facing south. This angle maximizes total annual energy production by accounting for the sun's changing position throughout the year and the varying solar irradiance levels at this latitude.

Environmental and Weather Challenges

Several significant factors at Janakpur Dham can impede solar energy production and require careful consideration during installation planning. The monsoon season presents the most substantial challenge to solar generation in this region. Heavy rainfall, dense cloud cover, and high humidity levels during monsoon months can dramatically reduce solar irradiance and panel efficiency. The moisture can also create condensation issues that affect electrical connections and panel performance. Dust accumulation is another major concern, particularly during dry periods before and after the monsoon. The Terai region of Nepal, where Janakpur Dham is located, experiences significant dust from agricultural activities and unpaved roads, which can coat solar panels and reduce their efficiency by blocking sunlight. High temperatures during summer months, while providing good solar irradiance, can actually reduce panel efficiency. Solar panels typically lose efficiency as temperatures rise above their optimal operating range, which can offset some of the benefits of increased sunlight.

Preventative Measures for Better Performance

Several installation strategies can help maximize solar energy production despite these environmental challenges:

• Install panels with adequate spacing and ventilation underneath to promote air circulation and reduce heat buildup
• Use high-quality waterproof electrical connections and junction boxes rated for high humidity conditions
• Implement regular cleaning schedules, especially during dusty periods, using appropriate cleaning methods that won't damage panels
• Consider installing panels at a steeper angle than the optimal 25 degrees in areas with heavy dust, as this helps with self-cleaning during rainfall
• Use anti-reflective coatings that are resistant to dust adhesion and easier to clean

Proper drainage around the installation site is crucial to prevent water pooling that could damage electrical components during heavy monsoon rains. Installing surge protection devices is also recommended due to the increased lightning activity during monsoon season. Regular maintenance becomes particularly important at this location, with inspections scheduled before and after monsoon seasons to ensure all connections remain secure and panels are functioning optimally. Despite these challenges, with proper installation and maintenance practices, Janakpur Dham can provide reliable solar energy generation throughout the year.

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 Janakpur Dham

Seasonal solar PV output for Latitude: 26.728, Longitude: 85.9285 (Janakpur Dham, 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 25° South in Janakpur Dham, Nepal

To maximize your solar PV system's energy output in Janakpur Dham, Nepal (Lat/Long 26.728, 85.9285) throughout the year, you should tilt your panels at an angle of 25° 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 Janakpur Dham, 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 Janakpur Dham, Nepal. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 25° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
11° South in Summer	32° South in Autumn	42° South in Winter	21° 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 Janakpur Dham, 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 Janakpur Dham, 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 Janakpur Dham, Nepal

Topography Around Janakpur Dham

Janakpur Dham sits in the heart of the Terai plains, Nepal's southernmost geographical region that forms part of the vast Indo-Gangetic plain stretching across northern India. This area represents some of the flattest terrain in Nepal, offering a dramatic contrast to the mountainous landscapes that dominate much of the country. The elevation around Janakpur Dham remains relatively consistent at approximately 80 to 100 meters above sea level, creating an expansive, gently undulating landscape that extends in all directions.

The topography is characterized by fertile alluvial soils deposited over millennia by rivers flowing down from the Himalayas. The terrain slopes very gradually southward toward the Indian border, with grade changes so subtle they are barely perceptible to the naked eye. This flat to gently rolling landscape is interrupted primarily by river channels, seasonal wetlands, and agricultural field boundaries rather than significant elevation changes.

Water features play a prominent role in shaping the local topography. Several rivers and their tributaries meander through the region, including seasonal waterways that swell during monsoon periods. These water bodies have created natural depressions and slightly elevated riverbanks, but even these variations rarely exceed a few meters in height difference from the surrounding plains.

Optimal Areas for Large-Scale Solar Development

The remarkably flat terrain surrounding Janakpur Dham presents exceptional opportunities for large-scale solar photovoltaic installations. The most suitable areas lie on the slightly elevated, well-drained lands between major river systems, where flooding risks remain minimal and ground conditions stay stable throughout seasonal variations.

Areas to the north and northwest of Janakpur Dham offer particularly favorable conditions, as these locations sit on marginally higher ground while maintaining the flat characteristics ideal for solar panel arrays. The terrain in these directions provides excellent drainage during monsoon seasons while avoiding the lowest-lying areas that may experience seasonal waterlogging.

The eastern and western approaches to the city also present viable options for solar development, especially on lands that currently serve as less productive agricultural areas or unused plots. These locations benefit from the same flat topography while potentially facing fewer land-use conflicts with prime agricultural zones.

Ground conditions throughout the region generally consist of stable alluvial soils that can adequately support solar mounting systems without requiring extensive foundation work. The absence of rocky outcrops, steep slopes, or significant elevation changes means that large solar installations can be developed with minimal grading or earthwork, reducing both construction costs and environmental impact.

Transportation access represents another advantage of the flat topography, as the level terrain facilitates the movement of equipment and materials to potential solar sites. The existing road network, built to serve the agricultural communities of the Terai, can accommodate the logistical requirements of large-scale solar construction and ongoing maintenance operations.

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.