Vacaville, California, located in the Northern Temperate Zone, offers a generally favorable environment for solar PV energy generation throughout the year. The city's geographical position at latitude 38.3862 and longitude -121.991 provides a good balance of sunlight exposure across seasons, making it a suitable location for solar power installations.

Seasonal Solar Performance

Solar energy production in Vacaville varies significantly across seasons. Summer stands out as the most productive period, with an impressive 8.49 kWh per day for each kilowatt of installed solar capacity. Spring follows closely, generating 7.50 kWh/day. Autumn sees a moderate decrease to 4.66 kWh/day, while winter experiences the lowest output at 2.82 kWh/day per kW installed.

The substantial difference between summer and winter production highlights the impact of seasonal variations on solar energy generation in this region. However, the relatively high output during spring and summer months can help offset the reduced winter production, contributing to a balanced annual energy yield.

Optimal Panel Installation

For fixed panel installations in Vacaville, the ideal tilt angle to maximize year-round solar production is 32 degrees facing south. This angle optimizes the panels' exposure to sunlight throughout the year, taking into account the changing position of the sun across seasons.

Environmental and Weather Considerations

While Vacaville generally provides favorable conditions for solar energy production, there are some environmental factors to consider:

• Fog: The region can experience fog, particularly in the mornings, which may temporarily reduce solar output.
• Wildfire smoke: California's susceptibility to wildfires can lead to periods of reduced air quality and sunlight obstruction.

To mitigate these issues, consider installing panels at a slightly steeper angle to allow morning dew or light fog to run off more easily. Additionally, regular cleaning and maintenance of panels can help minimize the impact of dust and particulate matter from wildfire smoke.

Overall, Vacaville's climate and geographical location make it a promising site for solar PV installations, with the potential for high energy yields, especially during the spring and summer months. While there are some environmental challenges, they can be largely addressed through proper installation techniques and maintenance practices.

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 Vacaville

Seasonal solar PV output for Latitude: 38.3862, Longitude: -121.991 (Vacaville, 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 32° South in Vacaville, United States

To maximize your solar PV system's energy output in Vacaville, United States (Lat/Long 38.3862, -121.991) throughout the year, you should tilt your panels at an angle of 32° 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 Vacaville, 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 Vacaville, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 32° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
22° South in Summer	42° South in Autumn	52° South in Winter	31° 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 Vacaville, 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 Vacaville, 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 Vacaville, United States

The topography around Vacaville, California, is characterized by a diverse landscape that transitions from flat valley floors to rolling hills and rugged mountains. Located in Solano County, Vacaville sits at the edge of the Sacramento Valley, where the flat agricultural lands begin to give way to the gentle slopes of the Coast Range. To the west of Vacaville, the terrain becomes increasingly hilly, with the English Hills and Vaca Mountains rising from the valley floor. These hills are part of the larger Coast Range system and offer scenic views of the surrounding area. The hills are generally covered with grasslands, oak woodlands, and scattered chaparral vegetation. East of Vacaville, the landscape is predominantly flat, consisting of fertile agricultural lands that stretch towards the Sacramento-San Joaquin River Delta. This area is part of the vast Central Valley of California, known for its rich soils and productive farmland.

Potential Areas for Large-Scale Solar PV

When considering areas nearby that would be most suited to large-scale solar photovoltaic (PV) installations, the flat, open spaces to the east of Vacaville present the most promising opportunities. These areas offer several advantages for solar energy development: Firstly, the flat terrain of the agricultural lands provides ample space for the installation of large solar arrays without the need for extensive land grading or modification. The lack of significant topographical features also means there are fewer obstacles that could cast shadows on the solar panels, maximizing their exposure to sunlight throughout the day. Secondly, this region experiences a high number of sunny days per year, which is crucial for optimal solar energy production. The Central Valley's climate, characterized by hot, dry summers and mild winters, is well-suited for solar power generation. Additionally, the proximity to existing power infrastructure in the Central Valley could potentially reduce the costs associated with connecting new solar installations to the grid. The area's agricultural heritage also means that there are already established road networks, which could facilitate the construction and maintenance of solar facilities. However, it's important to note that the use of productive agricultural land for solar energy production can be a contentious issue. Any large-scale solar development in this area would need to carefully balance energy production goals with the preservation of valuable farmland and local agricultural interests. In contrast, the hilly areas to the west of Vacaville, while scenic, are generally less suitable for large-scale solar PV installations due to their uneven terrain, which would complicate construction and potentially reduce the efficiency of solar panels due to varying angles and shadowing effects.

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.