Oeiras, Piauí, Brazil, situated at latitude -6.9085 and longitude -42.1749, offers an excellent location for solar photovoltaic (PV) energy generation throughout the year. Located in the tropics, this site benefits from consistent sunlight patterns that make it highly suitable for solar power installations.

The solar energy potential at this location shows impressive performance across all seasons. Winter stands out as the most productive period with an average daily output of 6.65kWh per kW of installed capacity. Spring follows closely behind at 6.56kWh/day. Summer and autumn produce 5.46kWh/day and 5.93kWh/day respectively per kW of installed capacity.

Interestingly, the winter-spring period provides the highest solar generation potential, which differs from what many might expect. This pattern is characteristic of tropical regions where the "winter" season often experiences clearer skies and less cloud cover than summer months, which can coincide with rainy seasons.

Optimal Panel Installation

For fixed solar panel installations in Oeiras, Piauí, the ideal tilt angle to maximize year-round energy production is 8 degrees facing North. This slight tilt helps optimize solar capture throughout the year, accounting for the sun's position as it varies across seasons at this near-equatorial location.

Environmental Considerations

Several environmental factors could potentially impact solar production in Oeiras:

• Dust accumulation during dry seasons can reduce panel efficiency by creating a film that blocks sunlight absorption
• Heavy rainfall during wet seasons may temporarily reduce solar output
• High temperatures in this tropical region can slightly decrease panel efficiency

To mitigate these challenges, several preventative measures are recommended. Installing panels with a self-cleaning tilt (which the recommended 8-degree angle helps facilitate) allows rainwater to naturally wash away dust. Regular maintenance cleaning, especially during dry periods, helps maintain optimal performance. Using heat-resistant, high-efficiency panels designed for tropical climates can minimize efficiency losses from high temperatures.

Overall, Oeiras presents an ideal location for solar PV installations with its consistently high solar irradiance throughout the year, particularly during winter and spring months. With proper installation practices and maintenance, solar energy systems in this location can deliver excellent returns on investment and reliable power generation.

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 3161 locations across Brazil. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Brazil by location

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

Seasonal solar PV output for Latitude: -6.9085, Longitude: -42.1749 (Oeiras, Brazil), 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 8° North in Oeiras, Brazil

To maximize your solar PV system's energy output in Oeiras, Brazil (Lat/Long -6.9085, -42.1749) throughout the year, you should tilt your panels at an angle of 8° North 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 Oeiras, Brazil

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 Oeiras, Brazil. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 8° North tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
9° South in Summer	14° North in Autumn	23° North in Winter	1° North 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 Oeiras, Brazil

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 Oeiras, Brazil.

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 Oeiras, Brazil

The topography surrounding Oeiras, in the northeastern Brazilian state of Piauí, is characterized by gently rolling terrain typical of the transition zone between the semi-arid sertão and the more humid cerrado biomes. The landscape features moderate elevation changes with an average altitude of approximately 170 meters above sea level. The terrain is predominantly composed of low hills and shallow valleys, with occasional rocky outcrops that punctuate the otherwise undulating landscape. The region experiences a tropical savanna climate with distinct wet and dry seasons. The natural vegetation consists primarily of drought-resistant shrubs and scattered trees, creating an open landscape with minimal natural shading. Soil composition tends toward sandy-clay mixtures with areas of exposed bedrock in certain locations.

Hydrological Features

The area is situated within the Canindé River basin, with several seasonal streams and small tributaries crossing the terrain. During the rainy season (December to April), these watercourses can swell significantly, while many become completely dry during the extended dry period. The Canindé River itself provides the most significant perennial water source in the vicinity, flowing roughly east to west to the south of Oeiras.

Optimal Areas for Solar PV Development

For large-scale solar photovoltaic installations, the most suitable areas near Oeiras would be the elevated plateaus and gently sloping hillsides that face northward. These locations offer several advantages: The higher elevation areas to the south and southwest of Oeiras present particularly favorable conditions. These zones feature minimal vegetation obstruction, stable soil conditions, and reduced flood risk compared to lowland areas near watercourses. The gradual slopes provide natural drainage while requiring minimal earthwork for installation. The northwestern corridor extending from Oeiras also contains promising terrain for solar development. This area features extensive stretches of open land with consistent elevation and minimal topographical barriers. The natural clearings in this region would require less preparation for solar array deployment. Areas to avoid would include the immediate floodplains of the Canindé River and its tributaries, as well as the more densely vegetated eastern approaches to the municipality where the terrain becomes more irregular and challenging for large installations. The geological stability of the region is generally favorable, with limited seismic activity and solid bedrock foundations in many areas. This provides good anchoring potential for solar mounting systems without excessive foundation requirements. From a topographical perspective, the combination of modest elevation, minimal shading obstacles, and relatively stable terrain makes the Oeiras region naturally conducive to solar energy development, particularly in the elevated areas to the south, southwest, and northwest of the urban center.

Brazil solar PV Stats as a country

Brazil ranks 13th in the world for cumulative solar PV capacity, with 13,708 total MW's of solar PV installed. This means that 2.50% of Brazil's total energy as a country comes from solar PV (that's 31st in the world). Each year Brazil is generating 64 Watts from solar PV per capita (Brazil ranks 47th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Brazil?

Yes, there are several incentives for businesses wanting to install solar energy in Brazil. The Brazilian government offers a range of tax credits and other financial incentives to encourage the adoption of renewable energy sources such as solar power. These include reduced import taxes on solar equipment, accelerated depreciation of investments in renewable energy projects, and preferential financing from public banks. Additionally, some states offer additional incentives such as subsidies or grants for businesses that install solar systems.

Do you have more up to date information than this on incentives towards solar PV projects in Brazil? 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.