Solar PV Analysis of Mililani Town, United States
Mililani Town, Hawaii, located in the United States, offers a favorable environment for solar energy generation throughout the year. Situated in the tropics, this location benefits from consistent sunlight and experiences wet and dry seasons rather than traditional four-season weather patterns.
Seasonal Solar Output
The solar energy production at Mililani Town varies across the meteorological seasons:
- Summer: 7.86 kWh/day
- Autumn: 6.19 kWh/day
- Winter: 4.90 kWh/day
- Spring: 7.19 kWh/day
Optimal Generation Periods
The location's proximity to the equator ensures relatively high solar energy production throughout the year. However, the summer months (June to August) offer the most favorable conditions for solar generation, followed closely by spring (March to May). Even during the winter months (December to February), which show the lowest output, the energy production remains substantial compared to many other locations.
Panel Installation Angle
For fixed panel installations in Mililani Town, the ideal tilt angle to maximize year-round solar production is 19 degrees facing South. This angle has been calculated considering the location's latitude, daily solar elevation angles, and weighted by NASA's solar irradiance data.
Environmental Considerations
While Mililani Town's tropical climate is generally conducive to solar energy production, there are a few environmental factors to consider: 1. Cloud cover: Hawaii's wet seasons can bring increased cloud cover, potentially reducing solar output. To mitigate this, consider installing slightly more capacity than initially calculated. 2. Volcanic activity: Although rare, volcanic eruptions on the islands can lead to ash in the atmosphere, temporarily reducing sunlight. Regular panel cleaning can help maintain efficiency in such events. 3. Salt air exposure: Being in close proximity to the ocean, salt air corrosion can affect solar equipment. Using marine-grade materials and applying protective coatings can extend the life of solar installations.
By taking these factors into account during installation and maintenance, solar energy systems in Mililani Town can achieve optimal performance and longevity, making the most of the location's favorable solar conditions.
Note: The Tropics are located between 23.5° North and -23.5° South of the equator.
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 Mililani Town
Seasonal solar PV output for Latitude: 21.4535, Longitude: -158.0193 (Mililani Town, 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 19° South in Mililani Town, United States
To maximize your solar PV system's energy output in Mililani Town, United States (Lat/Long 21.4535, -158.0193) throughout the year, you should tilt your panels at an angle of 19° 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 Mililani Town, 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 Mililani Town, United States. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 19° South tilt angle throughout the year.
| Overall Best Summer Angle | Overall Best Autumn Angle | Overall Best Winter Angle | Overall Best Spring Angle |
|---|---|---|---|
| 5° South in Summer | 27° South in Autumn | 37° South in Winter | 14° 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 Mililani Town, 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 Mililani Town, 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 Mililani Town, United States
Mililani Town is located in central Oahu, Hawaii, nestled in a relatively flat plateau between two mountain ranges. The area surrounding Mililani Town is characterized by a mix of gently rolling hills and more level terrain. To the east, the Koolau Mountain Range rises steeply, creating a dramatic backdrop to the town. To the west, the Waianae Mountain Range provides another mountainous border, though it's generally less steep and rugged than the Koolau Range.
The immediate vicinity of Mililani Town consists of residential areas, agricultural lands, and some forested regions. The terrain is generally mild, with subtle elevation changes throughout the area. This relatively flat topography is what made the region suitable for pineapple plantations in the past and urban development in more recent times.
When considering areas nearby that would be most suited to large-scale solar PV (photovoltaic) installations, several factors come into play. The ideal location would have abundant sunshine, relatively flat terrain, and be away from densely populated areas. Given these criteria, the following areas near Mililani Town could be potential candidates:
The agricultural lands to the north and northwest of Mililani Town, stretching towards Wahiawa, offer promising potential. These areas are relatively flat, receive ample sunlight, and are less densely populated. The former pineapple fields in this region could be repurposed for solar energy production.
Another area to consider would be the plains to the south of Mililani Town, extending towards Pearl City. While some of this land is currently used for agriculture or is part of military installations, there may be portions suitable for solar PV development.
It's important to note that any large-scale solar project would need to carefully consider environmental impacts, land use regulations, and community concerns. The unique ecosystem of Hawaii and the cultural significance of the land would need to be respected in any development plans. Additionally, the proximity to military installations might impose certain restrictions on land use in some areas.
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: Sunday 28th of July 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.
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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.
