Fairfield, Illinois, United States presents a moderately favorable location for year-round solar energy generation, though with significant seasonal variations typical of the Northern Temperate Zone climate.

Seasonal Solar Performance

The solar energy output at this location shows strong seasonal patterns. Summer delivers the highest production at 6.53 kWh per day per kW of installed solar capacity, making it the peak season for solar generation. Spring follows as the second-best performing season with 5.46 kWh per day per kW, offering excellent solar conditions as daylight hours increase and weather improves. Autumn production drops to 3.89 kWh per day per kW as the sun angle decreases and weather patterns change. Winter presents the most challenging conditions with only 2.40 kWh per day per kW, representing less than 40% of summer output levels. For optimal year-round energy capture at this location, solar panels should be installed on a fixed mounting system tilted at 33 degrees facing south. This angle maximizes total annual production by accounting for the sun's varying position throughout the year and the location's specific latitude.

Local Factors Affecting Solar Production

Several environmental and weather factors in the Fairfield area can significantly impact solar energy generation:

• Snow accumulation during winter months can completely block solar panels
• Ice formation creates both production barriers and safety hazards
• Severe thunderstorms common to Illinois can bring hail damage risks
• High humidity levels throughout much of the year can reduce solar efficiency
• Frequent cloud cover during certain seasons limits direct sunlight exposure

Preventative Installation Measures

To maximize solar production despite these challenges, several installation strategies prove effective. Panels should be mounted at steeper angles where possible to encourage natural snow shedding, while ensuring adequate spacing between panel rows to prevent snow accumulation and shading issues. Installing panels with anti-reflective coatings and tempered glass helps resist hail damage and reduces efficiency losses from humidity. Proper drainage systems around ground-mounted installations prevent water pooling that could create ice formation problems. Regular maintenance scheduling becomes crucial, particularly for snow removal during winter months and cleaning after storm events. Professional installation with robust mounting systems designed for local wind loads and weather extremes ensures long-term reliability and optimal energy production throughout the varying seasonal 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 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 Fairfield, Illinois

Seasonal solar PV output for Latitude: 38.3821, Longitude: -88.351 (Fairfield, 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 Fairfield, Illinois, United States

To maximize your solar PV system's energy output in Fairfield, Illinois, United States (Lat/Long 38.3821, -88.351) 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 Fairfield, 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 Fairfield, 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	53° 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 Fairfield, 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 Fairfield, 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 Fairfield, Illinois, United States

Topographical Features of Fairfield, Illinois

Fairfield is situated in the gently rolling agricultural landscape of southeastern Illinois, within Wayne County. The area is characterized by relatively flat to slightly undulating terrain typical of the Midwest's glaciated plains. The topography consists primarily of low-lying farmland with gradual elevation changes, creating an expansive landscape dotted with agricultural fields, scattered woodlots, and small creek valleys.

The region sits at a modest elevation, with the surrounding countryside featuring gentle slopes and broad, open areas that have been extensively cultivated for corn, soybeans, and other crops. Small streams and drainage ditches meander through the area, creating subtle variations in the otherwise predominantly flat terrain. These waterways, including various tributaries that eventually flow toward the Little Wabash River system, have carved shallow valleys that add gentle contours to the landscape.

The soil composition reflects the area's glacial history, with deep, fertile deposits that have made the region highly suitable for agriculture. This geological foundation has resulted in a landscape with minimal steep grades or significant topographical obstacles, making it relatively uniform in terms of elevation and slope characteristics.

Optimal Areas for Large-Scale Solar Development

The topographical characteristics around Fairfield present excellent opportunities for large-scale solar photovoltaic installations. The predominantly flat agricultural land provides ideal conditions for solar arrays, as the minimal slope variations reduce grading requirements and installation complexity. These open agricultural areas, particularly those with southern and southwestern exposures, would be most suitable for solar development due to their unobstructed access to sunlight throughout the day.

The areas immediately south and southwest of Fairfield offer particularly promising locations for solar farms. These zones combine the advantages of level terrain with optimal solar orientation, while remaining sufficiently distant from residential areas to minimize visual impact concerns. The existing agricultural infrastructure in these areas, including established road networks and proximity to electrical transmission lines, would facilitate the development and maintenance of solar installations.

Fields located on the higher, well-drained portions of the local topography would be preferable to lower-lying areas that might be subject to seasonal flooding or poor drainage. The slightly elevated agricultural lands to the west and northwest of town present ideal conditions, offering stable ground conditions and excellent accessibility for construction and ongoing maintenance operations.

The minimal tree cover in the actively farmed areas eliminates shading concerns that might affect solar panel efficiency, while the generally stable soil conditions provide a solid foundation for mounting systems. The gentle topography also allows for efficient water drainage around solar installations, preventing erosion issues that could arise in areas with steeper slopes or poor drainage characteristics.

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.