Solar PV Analysis of Seattle, United States
Seattle, Washington, United States (latitude: 47.6034, longitude: -122.3414) offers a suitable location for solar power generation with varying levels of energy production across different seasons. The average energy output per day for each kilowatt of installed solar capacity is as follows: 6.91 kWh in summer, 2.54 kWh in autumn, 1.33 kWh in winter, and 5.21 kWh in spring.
The higher energy production during the summer months can be attributed to increased sunlight availability compared to the winter season when sunlight is more limited. To optimize solar power generation at this location, it is recommended that panels are tilted at an angle of 39 degrees facing south.
It's important to note that certain environmental factors such as heavy rain or fog could potentially impede solar production by reducing the amount of sunlight available for energy generation at this location. To mitigate these effects and ensure greater energy production year-round, consider installing high-quality solar panels with better low-light performance and incorporating regular maintenance practices like cleaning the panels to remove dirt or debris that may obstruct sunlight absorption.
Overall, Seattle provides a viable environment for generating solar power throughout the year despite some seasonal fluctuations and potential weather-related challenges.
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 Seattle
Seasonal solar PV output for Latitude: 47.6034, Longitude: -122.3414 (Seattle, 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 39° South in Seattle, United States
To maximize your solar PV system's energy output in Seattle, United States (Lat/Long 47.6034, -122.3414) throughout the year, you should tilt your panels at an angle of 39° 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 Seattle, 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 Seattle, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 39° South tilt angle throughout the year.
| Overall Best Summer Angle | Overall Best Autumn Angle | Overall Best Winter Angle | Overall Best Spring Angle |
|---|---|---|---|
| 31° South in Summer | 50° South in Autumn | 62° South in Winter | 40° 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 Seattle, 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 Seattle, 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 Seattle, United States
The topography around Seattle is generally hilly and mountainous, with the Cascade Mountains to the east and the Olympic Mountains to the west. Areas that are most suitable for large-scale solar PV installations include flat areas such as lowlands, plains, and valleys that receive direct sunlight for most of the day. The nearby Snoqualmie Valley is an example of a good location for large-scale solar PV installations due to its flat terrain and ample sunshine. Additionally, rooftops in urban areas may also be suitable locations for solar PV systems.
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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Article Details for Citation
Author: Aaron Robinson
Publisher: profileSOLAR.com
First Published: Wednesday 10th of August 2022
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.
