Valongo, Santarém, Portugal, located at 39.7603° North, -8.5613° East, offers a reasonably good location for solar PV energy generation throughout the year, though with significant seasonal variations. This site in central Portugal experiences typical Mediterranean climate patterns that influence solar energy production.

Seasonal Solar Production

Solar energy generation at this location follows a predictable seasonal pattern. Summer stands out as the most productive period, with panels generating approximately 7.86kWh per day for each kilowatt installed. Spring follows as the second most productive season, yielding about 5.99kWh daily per kilowatt of capacity.

Production decreases considerably during autumn, with daily generation dropping to around 4.22kWh per kilowatt installed. Winter represents the least productive period, with output falling to just 2.37kWh daily per kilowatt of capacity—less than one-third of summer production.

Optimal Panel Installation

For fixed solar panel installations at this Valongo location, the ideal tilt angle to maximize year-round energy production is 34 degrees facing South. This angle has been calculated to optimize the total annual solar energy capture, accounting for seasonal variations in the sun's position and the Earth's elliptical orbit.

Environmental and Weather Considerations

Several factors could potentially impact solar production at this location. Fog and morning mist can be common in central Portugal, particularly during autumn and winter months, temporarily reducing panel efficiency during early daylight hours. Dust accumulation is another consideration in this Mediterranean climate, as dry summer periods can lead to significant dust buildup on panels.

Occasional Atlantic storms bringing heavy rainfall could temporarily decrease production, though they also provide natural panel cleaning. The region may also experience some wildfire risk during hot, dry summers, with smoke potentially reducing solar irradiance.

Preventative Measures

To maximize energy production despite these potential challenges, several preventative measures are recommended:

• Install an automated cleaning system or schedule regular manual cleaning to address dust accumulation, particularly before and after dry summer periods
• Consider slight adjustments to the tilt angle (perhaps 32-36 degrees) based on local microclimate conditions
• Implement quality surge protection to safeguard against lightning strikes during Atlantic storms
• Choose panels with anti-reflective coatings that perform better in diffuse light conditions during foggy periods
• Ensure adequate panel spacing and ground clearance to minimize dust accumulation and facilitate natural cleaning during rainfall

With these considerations addressed, Valongo offers a generally favorable location for solar energy generation, with particularly strong production potential from late spring through early autumn.

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 Valongo

Seasonal solar PV output for Latitude: 39.7603, Longitude: -8.5613 (Valongo, 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 34° South in Valongo, Portugal

To maximize your solar PV system's energy output in Valongo, Portugal (Lat/Long 39.7603, -8.5613) throughout the year, you should tilt your panels at an angle of 34° 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 Valongo, 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 Valongo, Portugal. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 34° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
24° South in Summer	44° South in Autumn	55° South in Winter	32° 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 Valongo, 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 Valongo, 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 Valongo, Portugal

The topography around Valongo, Portugal presents a diverse landscape characterized by rolling hills, valleys, and plateaus. Located in the northern region of Portugal, Valongo sits within a transitional zone between coastal plains and more mountainous interior terrain. The area features moderate elevation changes, with hills that generally range between 100 and 400 meters above sea level. The terrain surrounding Valongo is marked by several key topographical features. To the east, the landscape gradually rises toward the foothills of the Serra do Marão mountain range, creating a more rugged profile with steeper slopes and deeper valleys. Westward, the terrain becomes more gentle as it transitions toward the coastal plains near Porto and the Atlantic Ocean.

River Valleys and Watersheds

The region is intersected by several river valleys, most notably the Ferreira and Sousa rivers, which have carved distinct channels through the landscape over millennia. These river systems create natural corridors of flatter terrain amid the surrounding hills. The valleys typically feature alluvial soils and more level ground compared to the adjacent hillsides.

Forest Cover and Land Use

Much of the surrounding area features mixed forest cover, particularly pine and eucalyptus plantations, interspersed with agricultural land. These forested areas typically occupy the steeper slopes and higher elevations, while agricultural activities tend to concentrate in the more level areas and valley bottoms.

Potential for Solar PV Development

For large-scale solar photovoltaic development, several areas near Valongo show particular promise based on their topographical characteristics. The gently sloping plateaus to the south and southeast of Valongo offer ideal conditions for solar installations. These areas benefit from relatively level terrain that requires minimal grading, reducing construction costs while providing sufficient space for extensive arrays. The elevated plateaus between Valongo and Penafiel, approximately 10-15 kilometers to the east, present another promising zone. These higher elevation sites often experience less morning fog compared to the river valleys, potentially increasing solar exposure throughout the day. Areas of former agricultural land on south-facing slopes provide excellent opportunities for solar development. These locations combine favorable orientation toward the sun's path with already-cleared land, minimizing environmental impact and site preparation requirements.

Topographical Challenges

Not all areas around Valongo are equally suitable for solar development. The steeper slopes of the eastern hills present challenges for construction and maintenance of large installations. Similarly, the narrow river valleys, while flat, often have limited available space and may experience more shading from surrounding terrain features. The more densely forested sections would require significant clearing, raising both environmental concerns and development costs. Additionally, areas with northern slope aspects receive less direct sunlight throughout the year, reducing their potential energy yield compared to south-facing locations. In conclusion, the most suitable areas for large-scale solar PV development near Valongo would be the gently sloping, south-facing plateaus and hillsides that offer adequate space, reasonable access, and minimal topographical constraints. These areas combine the region's natural solar resource potential with terrain characteristics that facilitate efficient installation and operation of photovoltaic systems.

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.