Forest Grove, Oregon, in the United States offers varied solar energy potential throughout the year due to its location in the Northern Temperate Zone. This Pacific Northwest community experiences significant seasonal fluctuations in solar electricity production that potential solar adopters should understand.

Solar panels in Forest Grove produce their highest output during summer months, generating an impressive 7.13kWh per day for each kilowatt of installed capacity. This summer production is more than five times the winter output, making the warmer months clearly optimal for solar energy generation.

Spring represents the second-most productive season, with daily generation averaging 5.47kWh per kilowatt of installed capacity. This substantial production makes spring an excellent secondary season for solar energy harvesting in Forest Grove.

Autumn solar production drops considerably to 2.93kWh per day per kilowatt installed. While this represents less than half of spring production, it still provides meaningful energy contribution during fall months.

Winter presents the greatest challenge for solar production in Forest Grove, with output falling to just 1.38kWh per day per kilowatt installed. This significant seasonal variation highlights the importance of proper system sizing to accommodate winter's limited generation.

Optimal Panel Installation

For fixed solar panel installations in Forest Grove, the ideal angle to maximize year-round production is 38 degrees tilted toward the South. This carefully calculated angle balances seasonal solar variations to optimize annual electricity generation.

Environmental Considerations

Several environmental factors can impact solar production in Forest Grove:

• Pacific Northwest rain and cloud cover significantly reduce winter and autumn production, explaining the dramatic seasonal differences. While unavoidable, proper system sizing can accommodate these seasonal limitations.
• Forest Grove's proximity to forested areas may create shading issues depending on property location. A thorough shade analysis during site assessment can identify optimal panel placement to minimize tree shading.
• The region occasionally experiences ash and smoke from wildfires during summer months, which can temporarily reduce panel efficiency. Regular cleaning maintenance, especially following wildfire events, helps maintain optimal production.
• Winter ice and snow accumulation, though typically not prolonged, can temporarily halt production. Installing panels at the recommended 38-degree tilt helps facilitate natural snow shedding.

Despite these seasonal challenges, Forest Grove's excellent summer and spring production makes solar viable when systems are properly sized to account for the significant winter production decrease. The substantial difference between summer and winter output suggests that grid-connected systems with net metering would be particularly advantageous in this location.

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 Forest Grove

Seasonal solar PV output for Latitude: 45.5152, Longitude: -123.1191 (Forest Grove, 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 38° South in Forest Grove, United States

To maximize your solar PV system's energy output in Forest Grove, United States (Lat/Long 45.5152, -123.1191) throughout the year, you should tilt your panels at an angle of 38° 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 Forest Grove, 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 Forest Grove, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 38° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
29° South in Summer	48° South in Autumn	60° South in Winter	38° 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 Forest Grove, 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 Forest Grove, 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 Forest Grove, United States

Forest Grove, Oregon, is nestled in the eastern portion of the Coast Range foothills, situated in Washington County approximately 25 miles west of Portland. The topography around Forest Grove is characterized by a diverse landscape that transitions from the relatively flat Tualatin Valley in the east to the more undulating terrain of the Coast Range in the west. The immediate area surrounding Forest Grove features gently rolling hills with elevations ranging from about 180 feet above sea level in the valley floor to approximately 500 feet in the higher elevations within the city limits. This transitional zone between valley and mountains creates a varied terrain with numerous small creeks and streams that have carved shallow valleys throughout the region.

Surrounding Landscape Features

To the east of Forest Grove lies the broad, fertile Tualatin Valley, which consists primarily of flat to gently sloping agricultural lands. This valley floor, formed by ancient flood deposits, provides relatively level terrain that gradually slopes toward the Tualatin River. Moving westward from Forest Grove, the landscape becomes increasingly hilly as it transitions into the foothills of the Coast Range. These hills become progressively steeper and more densely forested, with elevations rising to over 1,500 feet within just a few miles west of the city. Notable high points in the vicinity include David Hill to the north and Gales Peak to the southwest. To the south, the terrain is characterized by a mix of rolling hills and small valleys, with the Chehalem Mountains rising in the distance. The northern landscape similarly features undulating hills that eventually give way to the floodplain of the Tualatin River.

Potential Solar PV Suitability

For large-scale solar photovoltaic installations, the most suitable areas near Forest Grove would be found in the flatter portions of the Tualatin Valley to the east and southeast of the city. These areas offer several advantages: The relatively flat agricultural lands in the Tualatin Valley provide large, contiguous spaces that would require minimal grading for solar array installation. These areas typically have fewer shading concerns from topographical features, allowing for maximum solar exposure throughout the day. The gently south-facing slopes found on the northern edges of the valley also present excellent opportunities for solar development. These slight inclines can actually improve solar panel efficiency by optimizing the angle of solar radiation. Areas to avoid would include the steeper western slopes of the Coast Range foothills, where increased forest cover, variable terrain, and potential morning shading issues could reduce efficiency. Similarly, narrow valleys running east-west might experience reduced direct sunlight due to shading from adjacent ridgelines. The north-facing slopes throughout the region would be less ideal for solar development due to reduced direct sun exposure, particularly during winter months when the sun's path is lower in the southern sky. The agricultural nature of much of the flat land presents both opportunities and challenges, as solar development would need to be balanced with preserving productive farmland. Some of the slightly elevated plateaus and terraces along the valley edges might offer good compromises, providing favorable solar conditions while utilizing land that may be less agriculturally productive.

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.