Ratmalana, Western Province, Sri Lanka, situated at 6.8165°N, 79.8634°E, presents a favorable location for solar PV energy generation throughout the year. This tropical setting benefits from consistent sunlight, with seasons primarily distinguished by wet and dry periods rather than temperature variations.

Seasonal Solar Performance

The solar energy output in Ratmalana demonstrates remarkable consistency across all seasons. Spring emerges as the most productive period, with an average daily output of 6.49 kWh per kW of installed solar capacity. Winter follows closely behind at 6.18 kWh/day, while summer yields 6.04 kWh/day. Autumn experiences a slight dip but still maintains a respectable 5.52 kWh/day. This minimal seasonal variation is a significant advantage for solar energy production in Ratmalana. It ensures a steady and reliable power supply throughout the year, reducing the need for alternative energy sources during less productive periods.

Optimal Panel Positioning

For fixed solar panel installations in Ratmalana, Western Province, the ideal tilt angle to maximize year-round energy production is 6 degrees facing South. This relatively shallow angle reflects the location's proximity to the equator, where the sun's path remains high in the sky throughout the year.

Environmental Considerations

While Ratmalana's climate is generally conducive to solar energy production, there are some environmental factors to consider: 1. Monsoon seasons: Sri Lanka experiences two monsoon seasons, which can lead to increased cloud cover and rainfall, potentially reducing solar efficiency. 2. High humidity: The tropical climate results in high humidity levels, which may affect solar panel performance and longevity. To mitigate these challenges, several preventative measures can be implemented:

Preventative Measures

1. Use corrosion-resistant materials for mounting systems and electrical components to combat humidity-related degradation. 2. Install robust waterproofing for all electrical connections to protect against heavy rainfall. 3. Implement a regular cleaning schedule to remove dust and debris, which can accumulate more quickly in humid environments. 4. Consider slightly oversizing the solar array to compensate for potential production losses during cloudy monsoon periods. By addressing these factors, solar installations in Ratmalana can maintain high efficiency and longevity, capitalizing on the location's excellent solar potential throughout the year.

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 109 locations across Sri Lanka. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Sri Lanka by location

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

Seasonal solar PV output for Latitude: 6.8165, Longitude: 79.8634 (Ratmalana, Sri Lanka), 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 6° South in Ratmalana, Sri Lanka

To maximize your solar PV system's energy output in Ratmalana, Sri Lanka (Lat/Long 6.8165, 79.8634) throughout the year, you should tilt your panels at an angle of 6° 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 Ratmalana, Sri Lanka

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 Ratmalana, Sri Lanka. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 6° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
9° North in Summer	12° South in Autumn	22° South in Winter	1° 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 Ratmalana, Sri Lanka

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 Ratmalana, Sri Lanka.

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 Ratmalana, Sri Lanka

Ratmalana, located in the western part of Sri Lanka, is characterized by a predominantly flat coastal landscape. The area surrounding Ratmalana is part of the Colombo District, which is known for its low-lying terrain with minimal elevation changes. The topography here is largely influenced by its proximity to the Indian Ocean, resulting in a mix of urban development and coastal features. The immediate vicinity of Ratmalana consists of a blend of residential areas, industrial zones, and pockets of open land. To the west, the coastline stretches along the Indian Ocean, featuring sandy beaches and occasional rocky outcrops. Moving inland towards the east, the landscape remains relatively flat, with subtle undulations rarely exceeding a few meters in height.

Nearby Areas Suitable for Large-scale Solar PV

When considering areas near Ratmalana for large-scale solar photovoltaic (PV) installations, several factors come into play. The flat terrain in the region is generally favorable for solar projects, as it minimizes the need for extensive land preparation and allows for efficient panel placement. One potentially suitable area for solar PV development is the land to the east and southeast of Ratmalana. This region, extending towards Homagama and Kaduwela, features larger tracts of open land with fewer urban developments. These areas benefit from the consistent tropical sunshine characteristic of Sri Lanka's climate, making them promising locations for solar energy production. Another promising location for solar PV installations could be found in the less densely populated areas to the northeast of Ratmalana, towards Kaduwela and Malabe. These regions offer a good balance of open space and proximity to existing infrastructure, which is crucial for connecting solar farms to the power grid. It's worth noting that while the coastal areas west of Ratmalana receive ample sunlight, they may not be ideal for large-scale solar projects due to their proximity to the ocean, potential for flooding, and higher land values associated with beachfront property. When planning solar PV installations, it's essential to consider factors beyond just topography. These include land availability, proximity to power infrastructure, environmental impact, and local regulations. Additionally, care must be taken to avoid ecologically sensitive areas or lands crucial for agriculture. In conclusion, while the flat terrain around Ratmalana offers potential for solar PV development, the most suitable areas are likely to be found in the less urbanized regions to the east and northeast. These areas combine favorable topography with the space required for large-scale installations, making them promising candidates for future solar energy projects in the region.

Sri Lanka solar PV Stats as a country

Sri Lanka ranks 55th in the world for cumulative solar PV capacity, with 434 total MW's of solar PV installed. Each year Sri Lanka is generating 20 Watts from solar PV per capita (Sri Lanka ranks 66th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Sri Lanka?

Yes, there are incentives for businesses wanting to install solar energy in Sri Lanka. The government of Sri Lanka 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 set up 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 Sri Lanka? 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.