McLean, Virginia, located in the United States, offers a moderately favorable environment for solar PV energy generation throughout the year. Situated in the Northern Temperate Zone, this location experiences distinct seasonal variations in solar energy production.

Seasonal Solar Performance

Summer stands out as the most productive season, with an impressive 6.46 kWh per day for each kW of installed solar capacity. Spring follows closely behind, generating 5.73 kWh/day. Autumn sees a noticeable decrease to 4.01 kWh/day, while winter experiences the lowest output at 2.47 kWh/day.

The substantial difference between summer and winter production highlights the impact of seasonal changes on solar energy generation in McLean. This variation is primarily due to changes in daylight hours and sun angle throughout the year.

Optimal Panel Placement

To maximize year-round solar energy production in McLean, fixed solar panels should be tilted at a 34-degree angle facing south. This optimal angle takes into account the location's latitude and the sun's changing position throughout the year, ensuring the best overall performance across all seasons.

Environmental Considerations

While McLean's climate is generally conducive to solar energy production, there are some environmental factors to consider:

• Snowfall: Winter snowfall can temporarily reduce panel efficiency. Regular snow removal or the installation of panels at a steeper angle can help mitigate this issue.
• Tree cover: McLean's abundant vegetation may cast shadows on solar panels. Careful site selection and tree trimming can minimize this impact.

Despite these challenges, McLean's location offers a good balance for solar energy production. With proper installation and maintenance, solar PV systems can provide significant energy output throughout the year, particularly during the spring and summer months.

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 McLean

Seasonal solar PV output for Latitude: 38.9307, Longitude: -77.1673 (McLean, 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 34° South in McLean, United States

To maximize your solar PV system's energy output in McLean, United States (Lat/Long 38.9307, -77.1673) throughout the year, you should tilt your panels at an angle of 34° 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 McLean, 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 McLean, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 34° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
23° South in Summer	43° South in Autumn	54° South in Winter	32° 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 McLean, 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 McLean, 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 McLean, United States

McLean, located in Fairfax County, Virginia, is situated in a region characterized by gently rolling hills and shallow valleys. The area's topography is typical of the Piedmont region, which forms a transitional zone between the flat coastal plain to the east and the more rugged Appalachian Mountains to the west. The landscape around McLean features a mix of low-lying areas and modest elevations, with the highest points generally reaching no more than 400 feet above sea level. The terrain is punctuated by numerous small streams and creeks that have carved shallow valleys over time. These waterways, including Scott's Run and Dead Run, flow eastward towards the Potomac River, which forms the eastern border of McLean.

Forested Areas and Green Spaces

Much of the natural landscape in and around McLean is covered in deciduous forests, with oak and hickory trees being particularly common. These wooded areas are interspersed with open spaces, including parks, golf courses, and residential developments. The presence of trees and varied terrain creates a picturesque setting but can pose challenges for large-scale solar energy projects.

Potential for Solar PV Development

When considering areas nearby that might be suitable for large-scale solar photovoltaic (PV) installations, it's important to look for relatively flat, open spaces with good sun exposure. While the immediate vicinity of McLean may not offer ideal conditions due to its suburban nature and forested areas, there are potential locations in the broader region that could be more suitable: 1. Former agricultural lands to the west and southwest of McLean, in Loudoun and western Fairfax counties, may offer more expansive, open areas for solar development. 2. Abandoned industrial sites or brownfields in nearby jurisdictions could be repurposed for solar installations, providing both renewable energy and land reclamation benefits. 3. Large commercial or institutional rooftops in more urbanized areas to the east, such as Tysons Corner or Falls Church, might be suitable for significant solar arrays without requiring additional land use. It's worth noting that any large-scale solar PV project in this region would need to carefully consider local zoning regulations, environmental impacts, and community preferences. The dense population and high land values in the Washington D.C. metropolitan area may present economic challenges for extensive ground-mounted solar installations. As such, innovative approaches like community solar projects or distributed rooftop systems might be more feasible alternatives in this particular geographic context.

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.