Sobral, Évora, Portugal, located in the Northern Temperate Zone at coordinates 38.735, -7.8122, offers varying conditions for solar PV energy generation throughout the year. This location experiences significant seasonal fluctuations in solar electricity production that are worth understanding when considering solar installations.

Seasonal Solar Production

Solar panels in Sobral demonstrate considerable seasonal variation in electricity output. During summer, production reaches its peak at 8.25kWh per day for each kilowatt of installed capacity. Spring follows as the second most productive season with 6.25kWh/day. Autumn sees a moderate decrease to 4.45kWh/day, while winter production drops significantly to just 2.56kWh/day per kilowatt installed.

This pattern creates a more than three-fold difference between the best and worst seasons, with summer generating approximately 222% more electricity than winter. The substantial drop during winter months means annual production is not evenly distributed.

Optimal Panel Installation

For fixed solar panel installations in Sobral, Évora, the ideal tilt angle to maximize year-round energy production is 33 degrees facing South. This carefully calculated angle balances seasonal variations to capture the most solar energy possible throughout the entire year.

Environmental Considerations

Several environmental factors could potentially impact solar production in Sobral:

• Dust and pollen accumulation can be significant in this region of Portugal, potentially reducing panel efficiency by 5-15% if not regularly cleaned. Installing automatic cleaning systems or scheduling quarterly maintenance can mitigate this issue.
• Occasional heat waves during summer months can reduce panel efficiency, as solar PV performance decreases slightly at very high temperatures. Ensuring adequate airflow beneath panels and using temperature-resistant components can help maintain production levels during hot periods.

Despite these considerations, Sobral's location offers excellent solar potential, particularly from April through September. The pronounced seasonal variation suggests that system sizing should account for winter's limited production if year-round energy independence is desired.

Note: The Northern Temperate Zone extends from 35° latitude North up to 66.5° latitude.

So far, we have conducted calculations to evaluate the solar photovoltaic (PV) potential in 179 locations across Portugal. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Portugal by location

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

Seasonal solar PV output for Latitude: 38.735, Longitude: -7.8122 (Sobral, Portugal), 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 33° South in Sobral, Portugal

To maximize your solar PV system's energy output in Sobral, Portugal (Lat/Long 38.735, -7.8122) throughout the year, you should tilt your panels at an angle of 33° 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 Sobral, Portugal

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 Sobral, Portugal. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 33° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
23° South in Summer	43° South in Autumn	54° South in Winter	31° 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 Sobral, Portugal

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 Sobral, Portugal.

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 Sobral, Portugal

The topography around Sobral, Portugal presents a varied landscape characteristic of the Alentejo region in the southeastern part of the country. This area is defined by gently rolling plains that gradually transition into more pronounced hills as one moves eastward toward the Spanish border. The immediate vicinity of Sobral sits at an elevation of approximately 240 meters above sea level, with the surrounding terrain generally ranging between 200-300 meters in elevation. The landscape is dominated by what locals call "montado" - a traditional agroforestry system featuring scattered cork and holm oak trees across open grasslands. This creates a somewhat sparse, savanna-like appearance that is distinctive to this region of Portugal. The Guadiana River valley influences the broader regional topography, with the river flowing north to south about 15 kilometers to the east of Sobral.

Terrain Characteristics

The terrain around Sobral exhibits a mild undulation rather than steep slopes or dramatic elevation changes. Small streams and seasonal waterways have carved shallow valleys throughout the area, creating a subtly contoured landscape. The underlying geology consists primarily of schist and granite formations, which contribute to the moderately fertile soils that have historically supported agriculture in the region. To the west of Sobral, the terrain becomes slightly flatter as it extends toward the central plains of Alentejo. Moving south, the landscape maintains its gently rolling character with occasional more prominent hills that rarely exceed 350 meters in height. The northern direction features similar topography with a gradual increase in elevation as one approaches the Serra de São Mamede mountain range, located approximately 40 kilometers from Sobral.

Optimal Areas for Solar PV Development

The most suitable areas for large-scale solar photovoltaic development near Sobral would be the gently sloping plains to the west and southwest of the settlement. These areas combine several favorable characteristics for solar installations: they feature minimal shadowing from topographical features, possess south-facing gentle slopes that optimize solar exposure throughout the day, and consist of relatively less productive agricultural land compared to other areas in the region. Specifically, the plateau areas extending 5-10 kilometers west of Sobral offer excellent potential for solar development. These locations provide large contiguous spaces with consistent elevation profiles, minimizing the engineering challenges and costs associated with uneven terrain. The natural drainage patterns in these areas also reduce the risk of seasonal flooding that could potentially damage infrastructure. The southeastern quadrant from Sobral also presents viable opportunities for solar development, featuring similar gently undulating terrain with favorable exposure aspects. These areas benefit from the rain shadow effect of higher elevations to the north and west, resulting in clearer atmospheric conditions that enhance solar irradiance efficiency. Areas to potentially avoid include the more steeply sloped terrain to the northeast, where the landscape begins to rise more dramatically, and the immediate riparian zones along the seasonal waterways that crisscross the region. These waterways, while often dry during summer months, can experience flash flooding during the winter rainy season, potentially compromising ground-mounted solar installations. The combination of favorable topography, relatively sparse vegetation coverage, and abundant open space makes the broader Sobral area naturally conducive to solar energy development, with the western plains representing the prime location for such initiatives based on topographical considerations alone.

Portugal solar PV Stats as a country

Portugal ranks 32nd in the world for cumulative solar PV capacity, with 1,801 total MW's of solar PV installed. This means that 3.40% of Portugal's total energy as a country comes from solar PV (that's 23rd in the world). Each year Portugal is generating 174 Watts from solar PV per capita (Portugal ranks 29th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Portugal?

Yes, there are several incentives for businesses wanting to install solar energy in Portugal. The Portuguese government offers a range of financial incentives and tax breaks for businesses that invest in renewable energy sources such as solar power. These include grants, loans, and tax credits. Additionally, the government has set up a feed-in tariff system which guarantees a fixed price for electricity generated from renewable sources such as solar power. This helps to make investing in solar energy more attractive to businesses.

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