Marion, Illinois, located in the Northern Temperate Zone, presents a moderately favorable location for year-round solar energy generation, though with significant seasonal variations that potential solar installers should carefully consider.

Seasonal Solar Performance

The solar energy output at this location shows a typical temperate climate pattern with substantial differences between seasons. Summer delivers the strongest performance at 6.60 kWh per day per kW of installed solar capacity, making it the peak production period. Spring follows as the second-best season with 5.58 kWh per day per kW, offering excellent solar generation potential. Autumn sees a notable decline to 4.07 kWh per day per kW, while winter presents the most challenging period with only 2.38 kWh per day per kW. This winter figure represents less than 40% of summer production, highlighting the importance of proper system sizing for year-round energy needs.

Optimal Installation Configuration

For fixed panel installations at Marion, Illinois, the ideal tilt angle is 33 degrees facing South to maximize total year-round solar production. This angle has been calculated by analyzing daily solar elevation angles throughout the year and weighting them according to solar irradiance data to achieve optimal annual energy harvest.

Local Factors Affecting Solar Production

Several environmental and weather factors in Marion, Illinois, can significantly impact solar energy production:

• Winter weather conditions including snow accumulation that can block panels
• Frequent cloud cover and overcast skies common in the Midwest
• High humidity levels that can reduce solar efficiency
• Severe weather events including thunderstorms and potential hail damage
• Seasonal temperature variations affecting panel efficiency

Preventative Measures for Enhanced Production

To maximize solar energy production despite these challenges, several installation strategies prove effective:

• Install panels at the recommended 33-degree tilt to promote natural snow shedding and optimize sun exposure
• Ensure adequate spacing between panel rows to minimize shading and allow for maintenance access
• Use high-quality mounting systems designed to withstand severe weather and potential hail impact
• Implement regular cleaning schedules to remove dust, debris, and snow accumulation
• Consider micro-inverters or power optimizers to minimize impact of partial shading from clouds

The location's moderate solar potential makes it suitable for solar installation, particularly when systems are properly designed to account for the significant seasonal variations and local weather challenges typical of southern Illinois.

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 4253 locations across the United States. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in the United States by location

Solar output per kW of installed solar PV by season in Marion, Illinois

Seasonal solar PV output for Latitude: 37.7241, Longitude: -88.9301 (Marion, Illinois, United States), 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 Marion, Illinois, United States

To maximize your solar PV system's energy output in Marion, Illinois, United States (Lat/Long 37.7241, -88.9301) 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 Marion, Illinois, United States

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 Marion, Illinois, United States. 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
22° South in Summer	42° South in Autumn	52° South in Winter	30° 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 Marion, Illinois, United States

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 Marion, Illinois, United States.

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 Marion, Illinois, United States

Topographical Features Around Marion

Marion sits within the gently rolling landscape of southern Illinois, positioned in the foothills of the Shawnee Hills region. The terrain around the city is characterized by moderate elevation changes, with the land rising and falling in gradual undulations rather than steep inclines. This area represents a transition zone between the flatter agricultural plains to the north and the more rugged terrain of the Shawnee National Forest to the south and east.

The elevation around Marion varies from approximately 400 to 600 feet above sea level, creating a landscape of low ridges and shallow valleys. These topographical features were shaped by ancient geological processes and glacial activity, resulting in well-drained uplands interspersed with creek bottoms and small floodplains. The soil composition varies across the region, with clay and silt predominating on the higher ground and alluvial deposits in the lower-lying areas.

Water features play a significant role in defining the local topography. Several creeks and streams flow through the area, creating natural drainage patterns that have carved gentle valleys into the landscape. These waterways generally flow in a southwesterly direction toward the Mississippi River system, creating ribbons of lower-lying land that contrast with the surrounding uplands.

Optimal Areas for Large-Scale Solar Development

The most suitable locations for large-scale solar photovoltaic installations around Marion would be the gently sloping upland areas that offer good drainage and relatively stable soil conditions. These elevated sites provide several advantages for solar development, including reduced risk of flooding, better air circulation for equipment cooling, and typically fewer obstacles such as mature tree cover.

The ridgetops and upper slopes northwest and southwest of Marion present particularly favorable conditions for solar farms. These areas feature gradual south-facing slopes that would naturally optimize solar panel orientation, while the elevated position provides excellent exposure to sunlight throughout the day. The terrain in these locations is gentle enough to minimize grading requirements while still providing the elevation needed for proper drainage.

Agricultural fields on the rolling uplands represent another prime opportunity for solar development. Much of the land around Marion has been cleared for farming, eliminating the need for extensive tree removal and environmental mitigation. These open areas already have established access roads and are typically located away from residential neighborhoods, reducing potential land-use conflicts.

Areas to avoid for large-scale solar installations include the creek bottoms and floodplains, where seasonal flooding could damage equipment and soft soils might not provide adequate foundation support. Similarly, the steeper slopes found in some parts of the Shawnee Hills region would require extensive grading and could present erosion challenges. Heavily forested areas, while potentially suitable from a topographical standpoint, would require significant clearing that could impact environmental permitting and project economics.

The moderate topography around Marion generally works in favor of solar development, as the terrain is varied enough to offer optimal site selection opportunities while remaining gentle enough to keep construction and maintenance costs reasonable. The combination of adequate elevation for drainage, manageable slopes for installation, and extensive cleared agricultural land creates favorable conditions for utility-scale solar projects in multiple directions from the city center.

United States solar PV Stats as a country

United States ranks 2nd in the world for cumulative solar PV capacity, with 95,209 total MW's of solar PV installed. This means that 3.40% of United States's total energy as a country comes from solar PV (that's 26th in the world). Each year United States is generating 289 Watts from solar PV per capita (United States ranks 15th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in United States?

Yes, there are several incentives for businesses wanting to install solar energy in the United States. These include federal tax credits, state and local rebates, net metering policies, and renewable energy certificates (RECs). Additionally, many states have enacted legislation that requires utilities to purchase a certain amount of electricity from renewable sources such as solar.

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