Covilha, Castelo Branco, Portugal, located at 40.2833° N, -7.508° E in the Northern Temperate Zone, offers varying solar energy potential throughout the year. This location experiences significant seasonal fluctuations in solar PV electricity generation, with production peaking in summer and dropping considerably during winter months.

Seasonal Solar Production

The solar energy output at this location follows a predictable seasonal pattern. During summer, solar panels generate an impressive 8.02 kWh per day for each kilowatt of installed capacity. Spring follows as the second most productive season with 5.90 kWh/day, while autumn delivers a moderate 4.00 kWh/day. Winter represents the challenging period with only 2.24 kWh/day of electricity generation per kW installed.

This seasonal variation means that Covilha's solar potential is substantially better during the warmer months from late spring through early autumn. The nearly four-fold difference between summer and winter production highlights the impact of seasonal changes at this latitude.

Optimal Panel Installation

For maximum year-round energy production in Covilha, Castelo Branco, fixed solar panels should be installed at a 34-degree tilt facing South. This specific angle optimizes the annual solar harvest by balancing seasonal variations in sun position and intensity throughout the year.

Environmental and Weather Considerations

Several factors may impact solar production in Covilha:

• The Serra da Estrela mountain range proximity can create localized cloud patterns and potential shading in certain areas.
• Winter fog is relatively common in this region, which can reduce solar generation during already low-production months.
• Occasional dust from the inland Iberian Peninsula, particularly during dry summer periods, may accumulate on panels.

To mitigate these challenges, installations should include regular cleaning protocols, especially before and after dry periods. Careful site assessment to avoid mountain shadows is essential, particularly for morning and evening sunlight. Additionally, using high-efficiency panels with good low-light performance can help maximize production during foggy winter days.

While Covilha experiences seasonal variations, its overall solar potential remains good by European standards, with particularly strong production from April through September making it suitable for solar PV investment.

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 Covilha

Seasonal solar PV output for Latitude: 40.2833, Longitude: -7.508 (Covilha, 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 Covilha, Portugal

To maximize your solar PV system's energy output in Covilha, Portugal (Lat/Long 40.2833, -7.508) 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 Covilha, 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 Covilha, 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	45° South in Autumn	55° South in Winter	33° 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 Covilha, 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 Covilha, 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 Covilha, Portugal

The topography surrounding Covilhã, Portugal is dominated by the Serra da Estrela mountain range, which forms part of the larger Central Massif system. Covilhã itself is positioned on the eastern slopes of Serra da Estrela at an elevation of approximately 700 meters above sea level. The town's unique position gives it a dramatic setting, with the urban area built along the mountainside, creating a terraced appearance when viewed from a distance.

Mountain Terrain

The Serra da Estrela mountains rise dramatically to the west of Covilhã, reaching Portugal's highest mainland point at Torre, which stands at 1,993 meters. These mountains feature rugged terrain with numerous valleys, rocky outcrops, and glacial formations shaped during the last ice age. The eastern slopes where Covilhã sits are generally steep, with numerous small streams and rivers cutting through the landscape as they flow down toward the Zêzere River valley.

River Valleys

The Zêzere River, one of Portugal's major waterways, flows near Covilhã, creating a fertile valley to the east. This river valley broadens as it moves eastward away from the mountains, transitioning into gentler terrain. Several smaller tributaries create additional valleys throughout the region, often with steep sides due to the erosive forces at work in this mountainous area.

Plains and Plateaus

Moving further east from Covilhã, the terrain gradually transitions to the higher plateaus of central Portugal. These areas feature more gentle, rolling landscapes compared to the dramatic mountain slopes directly surrounding the town. These plateaus, at elevations between 400-600 meters, offer more extensive flat or gently sloping terrain.

Potential for Solar PV Development

For large-scale solar photovoltaic (PV) installations, several areas near Covilhã present favorable conditions: The eastern plateaus extending toward Fundão and Castelo Branco offer the most promising locations for large-scale solar PV development. These areas combine relatively flat terrain with good solar exposure and fewer competing land uses than the fertile river valleys. The elevation is still beneficial for solar collection while avoiding the extreme conditions and difficult access of higher mountain areas. The broader sections of the Zêzere River valley, particularly moving southeast from Covilhã, provide another potential area for solar development. Though these areas may compete with agricultural uses, some portions offer suitable topography with minimal shading from surrounding mountains. Some of the gentler south-facing slopes at moderate elevations (400-600 meters) could also accommodate solar installations, though these would require more specialized construction techniques to address the sloping terrain.

Topographical Challenges

The immediate vicinity of Covilhã presents several challenges for large-scale solar development. The steep mountain slopes to the west are generally unsuitable due to their gradient, difficult access, and potential for shading. Additionally, many areas within the Serra da Estrela are protected as part of a natural park, limiting development possibilities. The northern aspects of many slopes receive significantly reduced direct sunlight, especially during winter months, making them poor candidates for solar installations regardless of other favorable characteristics. In conclusion, while Covilhã itself is nestled in mountainous terrain that presents challenges for large-scale solar development, the transitional areas to the east and southeast—where the mountains give way to plateaus and broader valleys—offer much more favorable conditions for substantial solar PV installations.

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.