Solar PV Analysis of Gresham, United States
Gresham, Oregon, located in the United States, presents a mixed picture for solar energy generation throughout the year. Situated in the Northern Temperate Zone at coordinates 45.4757, -122.4069, this location experiences significant seasonal variations in solar energy production.
Seasonal Solar Output
The solar energy potential in Gresham varies dramatically across the seasons. Summer stands out as the most productive period, with an impressive daily output of 7.15 kWh per kW of installed solar capacity. Spring follows as the second-best season, generating 5.52 kWh/day. However, autumn sees a significant drop to 2.96 kWh/day, while winter experiences the lowest output at just 1.42 kWh/day.
Optimal Installation
To maximize year-round solar energy production in Gresham, fixed solar panels should be installed at a tilt angle of 38 degrees facing south. This angle has been calculated to optimize energy capture across all seasons, taking into account the Earth's elliptical orbit and the location's specific latitude.
Environmental Factors
Several environmental factors can impact solar energy production in Gresham. The region's climate, characterized by wet winters and relatively dry summers, presents some challenges:
- Cloud cover: Frequent overcast conditions, especially during fall and winter, can significantly reduce solar output.
- Rain: The area receives considerable rainfall, particularly from October to May, which can affect panel efficiency.
Mitigation Strategies
To address these environmental challenges and optimize solar energy production, consider the following measures:
- Use high-efficiency panels designed to perform well in low-light conditions.
- Implement a robust cleaning schedule to remove dirt and debris, especially during drier months.
- Install a monitoring system to track performance and quickly identify any issues.
- Consider adding a solar tracking system to maximize energy capture, particularly during the productive summer months.
While Gresham's location presents some challenges for year-round solar energy production, proper system design and maintenance can help maximize the benefits of solar PV installation. The stark contrast between summer and winter output emphasizes the importance of grid connection or energy storage solutions to ensure consistent power supply throughout 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 Gresham
Seasonal solar PV output for Latitude: 45.4757, Longitude: -122.4069 (Gresham, 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 Gresham, United States
To maximize your solar PV system's energy output in Gresham, United States (Lat/Long 45.4757, -122.4069) 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 Gresham, 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 Gresham, 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 Gresham, 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 Gresham, United States.
Our calculation method
- Solar Position:
We determine the Sun's position on the Winter solstice using the location's latitude and solar declination. - Shadow Projection:
We calculate the shadow length cast by panels using trigonometry, considering panel tilt and the Sun's elevation angle. - 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 Gresham, United States
The topography around Gresham, Oregon, is characterized by a mix of flat urban areas and gently rolling hills. Gresham sits in the eastern part of the Portland metropolitan area, nestled between the Columbia River to the north and the foothills of the Cascade Mountains to the east.
The city itself is primarily built on relatively flat terrain, with some areas of gentle slopes. As you move east from Gresham, the landscape becomes more hilly and varied, with elevations gradually increasing towards the Cascade foothills. To the west, the land remains mostly flat as it extends towards Portland.
To the north of Gresham, the Columbia River Gorge creates a dramatic landscape with steep cliffs and deep valleys. South of the city, the terrain becomes more undulating with a mix of farmland and forested areas.
For large-scale solar PV installations, the most suitable areas nearby would likely be found to the east and southeast of Gresham. These regions offer more open, gently sloping landscapes that receive good sun exposure. The agricultural lands in the vicinity of Boring and Sandy, Oregon, could potentially provide suitable sites for solar farms.
Areas to the immediate north of Gresham might be less ideal due to the steep terrain of the Columbia River Gorge, which could create shading issues. The urban areas to the west would likely be too developed for large-scale installations. However, there may be opportunities for smaller-scale solar projects on rooftops or in urban settings within Gresham itself.
It's important to note that while topography is a crucial factor in determining suitable locations for solar PV, other considerations such as land availability, zoning regulations, grid connectivity, and environmental impact would also need to be carefully evaluated before establishing any large-scale solar projects in the region.
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!
Citation Guide
Article Details for Citation
Author: Aaron Robinson
Publisher: profileSOLAR.com
First Published: Thursday 5th of September 2024
Last Updated: Monday 21st of July 2025
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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.
