Washington, Pennsylvania, located at coordinates 40.1678, -80.2591 in the Northern Temperate Zone, presents a moderate location for solar PV energy generation with significant seasonal variations. This location experiences substantial differences in solar production throughout the year, with summer months being considerably more productive than winter.

Seasonal Solar Production

The solar energy production at this location varies dramatically by season. Summer stands out as the most productive period, generating an average of 6.08kWh per day for each kilowatt of installed capacity. Spring follows as the second most productive season with 5.32kWh/day. Autumn yields a moderate 3.40kWh/day, while winter production drops significantly to just 1.78kWh/day per installed kilowatt.

This means summer produces more than three times the electricity of winter months, creating a substantial seasonal disparity. The combined spring and summer seasons (approximately March through August) represent the ideal period for solar energy generation in Washington, Pennsylvania, accounting for nearly 70% of the annual production.

Optimal Panel Installation

For fixed solar panel installations at this location, the ideal tilt angle to maximize year-round production is 34 degrees facing South. This angle optimizes the annual solar capture by balancing seasonal variations and accounting for the Earth's elliptical orbit and the location's position in the Northern Hemisphere.

Environmental and Weather Considerations

Several significant factors may impede solar production at this Pennsylvania location:

• Snowfall accumulation during winter months can cover panels and dramatically reduce output during an already low-production season
• Cloud cover is relatively common in western Pennsylvania, particularly during winter and early spring
• Tree coverage and potential shading issues, as the region has significant deciduous forest areas
• Occasional airborne particulates from nearby industrial activities may reduce panel efficiency

Preventative Measures

To maximize solar production despite these challenges, several preventative measures should be considered during installation:

• Install panels at the steeper 34-degree angle to help shed snow more effectively
• Implement regular panel cleaning schedules, particularly after snowfall and during pollen seasons
• Consider microinverters or power optimizers to minimize the impact of partial shading
• Conduct thorough shade analysis before installation to avoid tree coverage issues
• Install slightly more capacity than needed to compensate for the significant winter production drop

While not ideal for year-round consistent production, Washington, Pennsylvania still receives sufficient solar radiation to make PV installations worthwhile, especially when properly designed to account for seasonal variations and local environmental factors.

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 Washington, Pennsylvania

Seasonal solar PV output for Latitude: 40.1678, Longitude: -80.2591 (Washington, Pennsylvania, 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 Washington, Pennsylvania, United States

To maximize your solar PV system's energy output in Washington, Pennsylvania, United States (Lat/Long 40.1678, -80.2591) 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 Washington, Pennsylvania, 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 Washington, Pennsylvania, 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
24° South in Summer	44° South in Autumn	55° South in Winter	33° 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 Washington, Pennsylvania, 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 Washington, Pennsylvania, 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 Washington, Pennsylvania, United States

The topography around Washington, Pennsylvania is characterized by rolling hills and valleys typical of the Appalachian Plateau region. Located in southwestern Pennsylvania, Washington sits within what geologists call the Allegheny Plateau, which has been deeply dissected by rivers and streams over millions of years, creating a landscape of moderate relief with elevations ranging generally between 900 to 1,300 feet above sea level. The terrain features a series of hills and ridges with intervening valleys, creating an undulating landscape rather than flat plains. The Monongahela River flows to the east of Washington, carving a significant valley through the plateau. Several smaller waterways, including Chartiers Creek, further divide the landscape into a network of smaller ridges and valleys.

Soil and Surface Features

The soils around Washington are predominantly derived from weathered sedimentary rocks, including sandstone, shale, and limestone. These soils vary in depth and quality, with steeper slopes having thinner soil layers due to erosion. The region's long history of coal mining and other extractive industries has also left its mark on the landscape, with some areas showing evidence of past mining activities. The natural vegetation consists primarily of deciduous forest, though much of the land has been cleared for agriculture, residential development, or industrial use. The combination of rolling topography and mixed land use creates a patchwork landscape typical of western Pennsylvania.

Optimal Areas for Solar PV Development

For large-scale solar photovoltaic (PV) installations near Washington, Pennsylvania, several topographical factors should be considered. The most suitable areas would include: South-facing slopes offer ideal conditions for solar collection in the northern hemisphere. The moderate hills around Washington provide numerous south-facing inclines that would receive more direct sunlight throughout the day and year compared to north-facing slopes. Elevated plateaus or ridgetops with minimal shading from surrounding terrain would be particularly valuable. Several of the broader hilltops in the region, especially those that have already been cleared of forest, could provide excellent sites for solar arrays. Reclaimed mine lands represent a significant opportunity for solar development in this region. Washington County and surrounding areas have numerous former mining sites that have been remediated but may not be suitable for other development. These often already-cleared, relatively flat areas could be repurposed for solar energy production without disrupting active agricultural or natural lands. Areas with proximity to existing electrical infrastructure would reduce the costs associated with connecting to the grid. The region around Washington has substantial energy infrastructure due to its industrial history, potentially offering good connection points for new solar installations. The agricultural valleys, while flat and accessible, represent a trade-off between solar development and preserving productive farmland. However, some agricultural operations might benefit from dual-use approaches where solar arrays are designed to allow for continued agricultural activities beneath or between panels. The rolling nature of the terrain does present some challenges for very large, contiguous solar installations, as extensive grading would be required for completely flat arrays. However, modern mounting systems can accommodate moderate slopes, and distributed installations across multiple suitable sites could collectively provide substantial generating capacity while working with the natural topography rather than against it.

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.