Roanoke, Alabama, located in the Northern Sub Tropics at latitude 33.1493, longitude -85.3714, offers a generally favorable location for solar PV energy generation throughout the year, though with notable seasonal variations.

Seasonal Solar Production

Solar energy production in Roanoke follows a predictable seasonal pattern. Summer stands out as the most productive season, generating approximately 6.14kWh per day for each kilowatt of installed solar capacity. Spring follows closely behind with 6.02kWh/day, making these warmer months ideal for solar energy harvesting.

Autumn sees a moderate decrease in production, with panels generating about 4.50kWh/day. Winter represents the challenging season for solar generation in Roanoke, with output dropping significantly to 2.76kWh/day per installed kilowatt.

Optimal Panel Installation

For fixed solar panel installations in Roanoke, the ideal tilt angle to maximize year-round energy production is 29 degrees facing South. This specific angle has been calculated to optimize solar capture across all seasons, accounting for the Earth's elliptical orbit and Roanoke's particular geographic position.

Environmental Considerations

Several environmental factors could potentially affect solar production in Roanoke:

• Thunderstorms and heavy rainfall, particularly during summer months, may temporarily reduce solar output during storm events.
• Occasional tornado activity in the region poses a physical risk to solar installations if not properly secured.
• Humidity levels in this subtropical climate can cause slight decreases in panel efficiency compared to drier regions.
• Tree coverage in this heavily forested region can create shading issues if not properly addressed during installation.

Preventative Measures

To maximize solar production despite these challenges, several preventative measures can be implemented. Robust mounting systems designed to withstand high winds should be used to protect against severe weather events. Regular panel cleaning schedules help mitigate efficiency losses from pollen, dust, and humidity-related residue that is common in subtropical environments.

Strategic tree trimming or removal may be necessary to prevent shading, particularly as the sun's path changes seasonally. Additionally, installing microinverters or power optimizers can help minimize production losses when partial shading is unavoidable.

Overall, with proper installation considerations and maintenance, Roanoke provides a viable location for solar energy production, with particularly strong generation potential during the spring and summer months.

Note: The Northern Sub Tropics extend from 23.5° latitude North up to 35° 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 Roanoke, Alabama

Seasonal solar PV output for Latitude: 33.1493, Longitude: -85.3714 (Roanoke, Alabama, 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 29° South in Roanoke, Alabama, United States

To maximize your solar PV system's energy output in Roanoke, Alabama, United States (Lat/Long 33.1493, -85.3714) throughout the year, you should tilt your panels at an angle of 29° 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 Roanoke, Alabama, 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 Roanoke, Alabama, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 29° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
17° South in Summer	38° South in Autumn	48° South in Winter	26° 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 Roanoke, Alabama, 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 Roanoke, Alabama, 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 Roanoke, Alabama, United States

Roanoke, Alabama sits in the southeastern United States in Randolph County, nestled in a region characterized by gentle rolling hills and modest valleys typical of the lower Appalachian foothills. The topography around Roanoke features elevations generally ranging between 700 and 900 feet above sea level, creating a moderately undulating landscape. The area is part of the Piedmont Plateau physiographic province, which serves as a transitional zone between the Appalachian Mountains to the north and the coastal plains to the south. The landscape surrounding Roanoke is dissected by numerous small streams and creeks that have carved shallow valleys throughout the region. These waterways are part of the Tallapoosa River watershed, with the Tallapoosa River itself flowing not far from the town. This river system has played a significant role in shaping the local topography over millions of years, creating the rolling terrain visible today.

Vegetation and Land Cover

The region around Roanoke is characterized by a mix of deciduous forests, agricultural lands, and open spaces. Pine and oak forests dominate many of the hillsides, while cleared agricultural fields and pastures occupy the flatter areas and valley bottoms. This mosaic of forested and open land reflects both the natural environment and human influence on the landscape over generations.

Potential for Solar PV Development

For large-scale solar photovoltaic (PV) installations, several areas near Roanoke offer promising conditions. The most suitable locations would be: The gently sloping agricultural lands to the south and southeast of Roanoke present ideal conditions for solar PV development. These areas feature relatively flat to slightly rolling terrain with southern exposure, maximizing potential solar capture. The existing agricultural use means these areas are already cleared of forest cover, reducing development costs and environmental impacts. Several elevated plateaus and broad ridgetops in the region, particularly to the northeast and southwest of Roanoke, offer excellent potential for solar installations. These higher elevation areas often receive consistent sunlight throughout the day with minimal shadowing from surrounding terrain features. The transitional lands between forest and agricultural use, particularly where marginal farmland exists, could be repurposed for solar development. These areas often have the advantage of being partially cleared while not representing prime agricultural land.

Topographical Challenges

While the Roanoke area does present good opportunities for solar development, certain topographical features pose challenges that would need to be addressed: The rolling nature of the terrain means that some areas experience shadowing during parts of the day, particularly in the more deeply cut valleys. Solar developers would need to conduct detailed site assessments to identify locations with optimal sun exposure throughout the day. The numerous small streams and associated floodplains in the region create areas where development would be inadvisable due to flood risk and environmental considerations. These waterways also fragment potential development sites, potentially limiting the scale of continuous installations. Some of the steeper slopes in the region would require significant grading work to prepare for solar installations, increasing development costs and potential erosion concerns. Despite these challenges, the moderate relief of the Piedmont landscape around Roanoke generally presents favorable conditions for solar PV development compared to more mountainous or densely forested regions elsewhere in the Appalachian range.

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.