The city of Velenje in Slovenia, situated at 46.3746°N, 15.0842°E, presents a mixed picture for solar energy generation throughout the year. This location in the Northern Temperate Zone experiences significant seasonal variations in solar output, which impacts the overall efficiency of photovoltaic (PV) systems.

Seasonal Solar Performance

Summer stands out as the most productive season for solar energy in Velenje, with an impressive average daily output of 6.55 kWh per kW of installed solar capacity. This high yield is due to longer daylight hours and more direct sunlight during the summer months. Spring follows as the second-best season, generating an average of 4.66 kWh per day. This period sees increasing daylight and improving weather conditions, making it a favorable time for solar energy production. Autumn experiences a noticeable decline in solar output, with an average daily production of 3.02 kWh. The shorter days and increased cloud cover contribute to this reduction. Winter presents the greatest challenge for solar energy generation in Velenje, with a significantly lower average daily output of 1.84 kWh. The combination of shorter days, lower sun angle, and potentially snowy or overcast conditions leads to this marked decrease in production.

Optimizing Solar Panel Installation

To maximize year-round solar energy production in Velenje, fixed solar panels should be installed at a tilt angle of 40 degrees facing south. This angle has been calculated to optimize the capture of available sunlight throughout the year, taking into account the location's latitude and seasonal variations in sun position.

Environmental and Weather Considerations

While Velenje's location is generally suitable for solar energy production, there are some factors that could potentially impact system performance: 1. Snow accumulation in winter: Regular panel cleaning or the installation of snow-shedding systems can help maintain efficiency during snowy periods. 2. Fog and cloud cover: Velenje experiences some foggy days, particularly in autumn and winter. Using high-efficiency panels and microinverters can help maximize energy production even in diffuse light conditions. 3. Air pollution: As an industrial city, Velenje may experience periods of increased air pollution. Regular panel cleaning and the use of anti-soiling coatings can mitigate the impact on solar production. By addressing these factors through proper system design and maintenance, solar PV installations in Velenje can achieve optimal performance despite the seasonal variations and local environmental conditions.

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

Link: Solar PV potential in Slovenia by location

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

Seasonal solar PV output for Latitude: 46.3746, Longitude: 15.0842 (Velenje, Slovenia), 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 40° South in Velenje, Slovenia

To maximize your solar PV system's energy output in Velenje, Slovenia (Lat/Long 46.3746, 15.0842) throughout the year, you should tilt your panels at an angle of 40° 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 Velenje, Slovenia

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 Velenje, Slovenia. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 40° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
30° South in Summer	49° South in Autumn	60° South in Winter	39° 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 Velenje, Slovenia

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 Velenje, Slovenia.

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 Velenje, Slovenia

The topography around Velenje, Slovenia is characterized by a mix of rolling hills, valleys, and low mountains. The city itself sits in a valley surrounded by gentle slopes and forested areas. To the north and east of Velenje, the terrain gradually rises into the foothills of the Kamnik-Savinja Alps, with elevations increasing as you move further from the city.

The Šalek Valley, where Velenje is located, is relatively flat and open, with the Paka River running through it. This valley is flanked by hills on both sides, creating a somewhat enclosed landscape. To the south and west, the terrain becomes more varied, with a series of hills and small valleys dotting the landscape.

When considering areas nearby that would be most suited for large-scale solar PV (photovoltaic) installations, there are a few factors to consider. Ideally, solar farms require relatively flat or gently sloping land with good sun exposure throughout the day. Based on the topography around Velenje, the following areas might be suitable:

The open areas within the Šalek Valley, particularly to the east and west of Velenje, could be potential sites for solar installations. These areas are relatively flat and may have fewer obstructions to sunlight. However, it's important to consider that some of this land may already be used for agriculture or other purposes.

The south-facing slopes of the hills surrounding the valley might also be good candidates for solar farms. These areas would receive more direct sunlight throughout the day, especially if they're not heavily forested. The gentle slopes could actually be advantageous, as they would naturally angle the solar panels towards the sun.

It's worth noting that while the mountainous areas to the north might seem appealing due to their elevation, they may not be ideal for large-scale solar installations. The steeper terrain and potential for more cloud cover at higher elevations could reduce the efficiency of solar panels in these locations.

Ultimately, the selection of sites for solar PV would require detailed local surveys, taking into account not just topography but also factors like land ownership, proximity to power infrastructure, and local environmental considerations.

Slovenia solar PV Stats as a country

Slovenia ranks 60th in the world for cumulative solar PV capacity, with 367 total MW's of solar PV installed. Each year Slovenia is generating 175 Watts from solar PV per capita (Slovenia ranks 28th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Slovenia?

Yes, there are incentives for businesses wanting to install solar energy in Slovenia. The Slovenian government offers a range of financial incentives and subsidies for businesses that install solar energy systems. These include grants, tax credits, and other forms of support. Additionally, the government has set up a number of programs to promote the use of renewable energy sources such as solar power.

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