Joliet, Illinois, located in the Northern Temperate Zone at coordinates 41.4893, -88.159, presents a varied landscape for solar PV energy generation throughout the year. The location experiences significant seasonal fluctuations in solar output, which impacts the overall efficiency of solar installations.

Seasonal Solar Performance

Summer stands out as the most productive season for solar energy in Joliet, with an impressive daily output of 6.25 kWh per kW of installed solar capacity. Spring follows closely behind, generating 5.29 kWh/day. However, the colder months see a substantial drop in production, with autumn yielding 3.39 kWh/day and winter bottoming out at 2.35 kWh/day.

These figures indicate that solar energy generation in Joliet is most effective from late spring through early fall. During this period, longer days and higher sun angles contribute to increased solar panel efficiency. Conversely, the shorter days and lower sun angles of late fall and winter significantly reduce solar output.

Optimal Panel Installation

To maximize year-round solar production in Joliet, fixed solar panels should be installed at a tilt angle of 36 degrees facing south. This angle optimizes the panels' exposure to sunlight throughout the year, balancing the seasonal variations in sun position and intensity.

Environmental and Weather Considerations

Joliet's climate presents some challenges for solar energy production. The area experiences cold winters with occasional heavy snowfall, which can temporarily reduce panel efficiency. To mitigate this, panels can be installed at a steeper angle to encourage snow sliding off. Regular maintenance to remove snow accumulation may also be necessary.

Additionally, Joliet is subject to severe weather events, including thunderstorms and tornadoes. While these occurrences are relatively infrequent, they can pose a risk to solar installations. To address this, robust mounting systems and impact-resistant panels should be used. It's also advisable to include lightning protection systems in the installation.

Despite these challenges, with proper planning and installation techniques, Joliet remains a viable location for solar PV energy generation, particularly during the warmer months of the year.

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 Joliet, Illinois

Seasonal solar PV output for Latitude: 41.4893, Longitude: -88.159 (Joliet, 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 36° South in Joliet, Illinois, United States

To maximize your solar PV system's energy output in Joliet, Illinois, United States (Lat/Long 41.4893, -88.159) throughout the year, you should tilt your panels at an angle of 36° 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 Joliet, 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 Joliet, Illinois, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 36° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
26° South in Summer	45° South in Autumn	55° South in Winter	34° 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 Joliet, 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 Joliet, 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 Joliet, Illinois, United States

The topography around Joliet, Illinois, is characterized by gently rolling plains and relatively flat terrain. This area, located in the northeastern part of the state, is part of the larger Midwest region known for its prairie landscapes. The city of Joliet and its surrounding areas sit on what was once glacial terrain, shaped by the retreat of massive ice sheets thousands of years ago. The landscape is predominantly composed of low-lying areas with subtle elevation changes. The Des Plaines River runs through Joliet, creating a shallow valley that adds some variation to the otherwise level ground. Small hills and modest ridges can be found scattered throughout the region, but dramatic changes in elevation are rare.

Soil Composition and Land Use

The soil in and around Joliet is generally fertile, a result of glacial deposits and the area's prairie history. This has made the region well-suited for agriculture, with many farms and fields surrounding the urban areas. The combination of rich soil and relatively flat terrain has allowed for extensive cultivation of crops like corn and soybeans.

Potential for Solar PV Development

When considering areas nearby that would be most suited to large-scale solar PV installations, several factors come into play. The flat to gently rolling terrain around Joliet offers numerous advantages for solar development. Large, open spaces with minimal shading from natural features are abundant, which is ideal for maximizing solar exposure throughout the day. Rural areas to the south and west of Joliet present particularly promising opportunities for solar PV projects. These locations often feature expansive agricultural lands that could potentially accommodate solar arrays without significant alterations to the landscape. The relatively low population density in these areas also means less competition for land use and fewer concerns about visual impact on residential communities.

Considerations for Solar Development

While the topography is generally favorable, potential developers would need to consider factors such as proximity to existing electrical infrastructure, local zoning regulations, and environmental impact assessments. Areas near major roads or transmission lines might be particularly attractive due to easier access and reduced costs for connecting to the grid. It's worth noting that while the region experiences all four seasons, including snowy winters, the overall climate still provides ample sunlight for solar energy production. The flat terrain also means that wind is less likely to be obstructed, which can help keep solar panels cool and operating efficiently during warmer months. In conclusion, the topography around Joliet offers a conducive environment for large-scale solar PV development, with its open spaces and minimal elevation changes. The areas to the south and west of the city, where agricultural land is prevalent, appear to be the most promising for such projects, balancing the need for space with accessibility and existing land use patterns.

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.