Inaruwa, Koshi, Nepal presents a moderately favorable location for year-round solar energy generation, with its position in the Northern Sub Tropics at coordinates 26.6165° North, 87.1505° East offering consistent solar potential throughout the year.

Seasonal Solar Performance

The location demonstrates varying solar energy output across different seasons, with spring being the most productive period at 5.59 kWh per day per kW of installed solar capacity. This peak performance in spring is followed by autumn at 4.54 kWh/day, summer at 4.46 kWh/day, and winter showing the lowest output at 3.73 kWh/day per kW installed. Spring emerges as the ideal time for solar generation at this location, producing approximately 50% more energy than the winter months. The relatively strong performance during autumn and summer ensures that the location maintains decent solar production for three-quarters of the year, with only winter showing a notable decline. For optimal year-round energy production, solar panels should be installed at a fixed tilt angle of 25 degrees facing south. This angle has been calculated to maximize total annual solar output by accounting for the sun's varying position throughout the year and the Earth's elliptical orbit around the sun.

Environmental and Weather Challenges

Several significant local factors could impede solar production at Inaruwa, Koshi, requiring careful consideration during installation planning. The monsoon season presents the most substantial challenge to solar energy generation in this region. Heavy rainfall and prolonged cloud cover during monsoon months can dramatically reduce solar irradiance, contributing to the lower winter production figures. The high humidity levels associated with monsoons can also lead to increased soiling of solar panels and potential corrosion issues. Dust accumulation poses another significant concern, particularly during dry periods. The location's proximity to agricultural areas and unpaved roads can result in substantial dust buildup on solar panels, reducing their efficiency by blocking sunlight from reaching the photovoltaic cells.

Preventative Measures for Optimal Performance

Several installation strategies can help mitigate these environmental challenges and ensure better energy production:

• Install panels with adequate spacing and proper drainage systems to prevent water accumulation during heavy rains
• Use mounting systems that allow for easy cleaning and maintenance access
• Implement regular cleaning schedules, particularly before and after monsoon seasons
• Choose solar panels and mounting hardware with enhanced corrosion resistance suitable for high-humidity environments
• Install bypass diodes and optimizers to minimize the impact of partial shading from clouds or debris

Regular maintenance becomes crucial at this location, with monthly cleaning recommended during dry seasons and immediate post-storm inspections during monsoon periods. Proper system design should also include adequate ventilation behind panels to prevent overheating during humid conditions, which can reduce solar panel efficiency. Despite these challenges, Inaruwa's consistent year-round solar potential makes it a viable location for solar energy projects, provided that appropriate installation techniques and maintenance protocols are followed to address the local environmental conditions.

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 Inaruwa

Seasonal solar PV output for Latitude: 26.6165, Longitude: 87.1505 (Inaruwa, 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 Inaruwa, Nepal

To maximize your solar PV system's energy output in Inaruwa, Nepal (Lat/Long 26.6165, 87.1505) 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 Inaruwa, 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 Inaruwa, 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
10° 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 Inaruwa, 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 Inaruwa, 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 Inaruwa, Nepal

Topographical Features of Inaruwa

Inaruwa sits in the southeastern region of Nepal within the Terai plains, a relatively flat lowland area that extends along the country's southern border with India. This location places it at a moderate elevation of approximately 150 meters above sea level, making it part of the transitional zone between the flat Gangetic plains to the south and the rising foothills of the Himalayas to the north. The immediate landscape around Inaruwa is characterized by gently rolling terrain with minimal elevation changes. The area features fertile alluvial soils deposited by rivers flowing down from the mountains, creating a predominantly agricultural landscape. Small streams and seasonal watercourses meander through the region, though these do not create significant topographical obstacles or steep valleys. Moving northward from Inaruwa, the terrain gradually begins to rise as it approaches the Churia Hills, also known as the Siwalik Range. These foothills represent the southernmost extension of the Himalayan mountain system, with elevations increasing progressively from around 300 meters to over 1,000 meters. The transition from the Terai plains to these hills creates a varied topographical profile with moderate slopes and occasional ridgelines.

Optimal Locations for Large-Scale Solar Development

The flat to gently undulating terrain of the Terai plains surrounding Inaruwa presents excellent opportunities for large-scale solar photovoltaic installations. The minimal elevation changes across extensive areas reduce the need for complex grading and earthwork, significantly lowering construction costs and simplifying project logistics. Areas immediately south and southwest of Inaruwa offer particularly favorable conditions for solar development. These zones maintain consistent gentle slopes with good natural drainage while avoiding the more agriculturally intensive river valleys. The terrain in these areas typically features gradual elevation changes of less than 5 degrees, ideal for optimizing panel orientation and minimizing shading between solar array rows. The eastern plains extending toward the Indian border also present suitable topography for solar installations. This region benefits from relatively uniform terrain with good accessibility via existing road networks. The land here is less dissected by watercourses compared to areas closer to major river systems, providing larger contiguous parcels suitable for utility-scale solar farms. Areas to the north, while offering some suitable terrain, begin to encounter the complications of steeper slopes and more complex topography as they approach the Churia Hills. However, certain ridge tops and plateau areas within this transitional zone could accommodate smaller solar installations, particularly where the terrain levels out between hill formations. The western approaches to Inaruwa feature similar favorable conditions to the southern areas, with extensive flat to gently rolling terrain. These locations benefit from good drainage characteristics and minimal topographical constraints, though careful site selection would be necessary to avoid seasonal flooding zones associated with monsoon runoff patterns.

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.