Yamaguchi, Japan, situated at latitude 34.1868 and longitude 131.4645 in the Northern Sub Tropics, offers a moderately favorable location for solar PV energy generation throughout the year. The seasonal electricity output varies significantly, with the highest production occurring during summer and spring months.

Seasonal Solar Performance

Solar panels in Yamaguchi demonstrate strong performance during the warmer months, generating 5.37kWh per day for each kilowatt installed during summer and a comparable 5.19kWh/day in spring. However, production decreases considerably during autumn to 3.71kWh/day, and reaches its lowest point in winter with only 2.63kWh/day per installed kilowatt.

This seasonal pattern indicates that Yamaguchi experiences about twice the solar energy production in summer compared to winter, which is typical for locations in the Northern Hemisphere at this latitude. The relatively strong spring performance suggests that March through May offer excellent solar harvesting opportunities, nearly matching summer levels.

Optimal Panel Installation

For fixed solar panel installations in Yamaguchi, the ideal tilt angle to maximize year-round energy production is 30 degrees facing South. This angle has been carefully calculated to optimize annual solar collection based on Yamaguchi's specific latitude and seasonal solar patterns.

Environmental Considerations

Several environmental factors could potentially impact solar production in Yamaguchi:

• Typhoon exposure: Yamaguchi Prefecture faces the Sea of Japan and can experience typhoons during summer and early autumn. Installing sturdy mounting systems with wind resistance certification is essential.
• High humidity and rainfall: The subtropical climate brings significant precipitation, especially during the rainy season (June-July). Using panels with good anti-soiling properties and ensuring proper drainage around installations can mitigate power losses.
• Snow accumulation: While not excessive, winter snowfall can temporarily reduce output. Installing panels at the recommended 30-degree tilt helps with snow shedding.
• Salt exposure: Proximity to the coast may expose panels to salt spray. Using marine-grade components and regular cleaning can prevent corrosion and performance degradation.

With proper installation considerations addressing these regional factors, solar PV systems in Yamaguchi can effectively capitalize on the strong spring and summer production periods while minimizing losses during the less productive autumn and winter months.

Note: The Northern Sub Tropics extend from 23.5° latitude North up to 35° latitude.

So far, we have conducted calculations to evaluate the solar photovoltaic (PV) potential in 187 locations across Japan. This analysis provides insights into each city/location's potential for harnessing solar energy through PV installations.

Link: Solar PV potential in Japan by location

Solar output per kW of installed solar PV by season in Yamaguchi

Seasonal solar PV output for Latitude: 34.1868, Longitude: 131.4645 (Yamaguchi, Japan), 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 30° South in Yamaguchi, Japan

To maximize your solar PV system's energy output in Yamaguchi, Japan (Lat/Long 34.1868, 131.4645) throughout the year, you should tilt your panels at an angle of 30° 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 Yamaguchi, Japan

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 Yamaguchi, Japan. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 30° South tilt angle throughout the year.

Overall Best Summer Angle	Overall Best Autumn Angle	Overall Best Winter Angle	Overall Best Spring Angle
18° South in Summer	39° South in Autumn	49° South in Winter	27° 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 Yamaguchi, Japan

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 Yamaguchi, Japan.

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 Yamaguchi, Japan

Yamaguchi city is nestled in western Japan's Yamaguchi Prefecture, characterized by a diverse topographical landscape that blends mountainous terrain with coastal plains. The city sits in a basin surrounded by mountains on three sides, with the northern area opening toward the Sea of Japan. This geographic position creates a unique setting where urban development has concentrated in the relatively flat basin areas while preserving the natural mountainous surroundings.

Mountain Features

The region around Yamaguchi is dominated by the Chugoku Mountain Range, which runs through the prefecture. Notable peaks include Mount Jakuchi and several other mountains exceeding 600 meters in elevation. These mountains create distinct microclimates throughout the region and influence weather patterns. The mountainous terrain generally features forested slopes with varying degrees of steepness, some areas having gradual inclines while others present more dramatic topographical changes.

Valleys and Waterways

Between the mountains lie several river valleys that have historically supported agriculture and settlement. The Fushino River flows through Yamaguchi city, creating fertile plains that have been cultivated for centuries. These valley floors provide some of the limited flat land in the prefecture. Numerous smaller streams and tributaries cut through the landscape, creating natural drainage systems that have shaped the local topography over millennia.

Coastal Areas

While Yamaguchi city itself is inland, the prefecture extends to both the Sea of Japan coastline to the north and the Seto Inland Sea to the south. These coastal areas feature different topographical characteristics, with some sections having rocky shores and others presenting sandy beaches. The varied coastline includes natural harbors and bays that have supported fishing communities and maritime trade throughout history.

Potential Areas for Solar PV Development

For large-scale solar photovoltaic installations, several areas near Yamaguchi present favorable conditions based on topographical considerations: The broader valley floors within the Yamaguchi Basin offer relatively flat terrain that would minimize grading costs for solar installations. These areas typically have good solar exposure without significant shadowing from mountain ranges, particularly in the central and southern portions of the basin. Gently sloping hillsides facing south or southwest provide excellent potential for solar development. These areas receive consistent sunlight exposure throughout the day and benefit from optimal sun angles. Several such locations exist in the transitional zones between the basin floor and the steeper mountain slopes. Reclaimed or underutilized agricultural land in the river valleys presents opportunities for solar development without requiring significant land clearing. These areas are generally accessible by existing road networks and may be close to electrical infrastructure.

Topographical Limitations

Despite these opportunities, certain topographical features present challenges for large-scale solar development. The steeper mountainous areas, while receiving good sunlight, would require extensive and costly terrain modification. Additionally, north-facing slopes receive significantly reduced direct sunlight due to shadowing effects from the mountains themselves. Narrow valley sections where mountains create extended morning or evening shadows would experience reduced daily electricity generation potential. These areas, particularly in the deeper mountain valleys to the east and west of the city, would be less suitable for commercial-scale installations. The region's varied elevation changes also create challenges for construction and maintenance access, potentially increasing development costs in more remote or rugged areas. However, modern solar mounting systems designed for varied terrain can mitigate some of these challenges in moderately sloping areas.

Japan solar PV Stats as a country

Japan ranks 3rd in the world for cumulative solar PV capacity, with 74,191 total MW's of solar PV installed. This means that 8.30% of Japan's total energy as a country comes from solar PV (that's 9th in the world). Each year Japan is generating 590 Watts from solar PV per capita (Japan ranks 4th in the world for solar PV Watts generated per capita). [source]

Are there incentives for businesses to install solar in Japan?

Yes, there are several incentives for businesses wanting to install solar energy in Japan. These include the Feed-in Tariff (FIT) program, which provides a fixed price for electricity generated from renewable sources such as solar; subsidies and grants from local governments; tax credits; and loans with low interest rates. Additionally, businesses may be eligible for additional incentives depending on their location and type of installation.

Do you have more up to date information than this on incentives towards solar PV projects in Japan? 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.