Nakatsugawa, Japan, located at latitude 35.485 and longitude 137.4998, offers a moderately favorable location for solar PV energy generation throughout the year, with seasonal variations that affect energy production.

Seasonal Solar Production

Solar panels in Nakatsugawa demonstrate clear seasonal patterns in electricity generation. Summer yields the highest output at 5.23 kWh per day for each kW of installed capacity, followed closely by spring with 5.11 kWh/day. Production decreases considerably in autumn to 3.76 kWh/day, with winter showing the lowest generation at 2.93 kWh/day per kW installed.

This seasonal pattern indicates that Nakatsugawa experiences approximately 44% less solar production during winter months compared to peak summer performance. The location benefits from strong solar potential during half the year (spring and summer), with more modest returns during autumn and winter.

Optimal Panel Installation

For fixed solar panel installations in Nakatsugawa, the ideal tilt angle to maximize year-round energy production is 32 degrees facing South. This angle optimizes the capture of solar radiation throughout the year, balancing the seasonal variations in sun position and intensity.

Environmental Considerations

Several environmental factors in Nakatsugawa can impact solar energy production:

• Snow accumulation during winter months can temporarily reduce panel efficiency by blocking sunlight. Installing panels at the recommended 32-degree tilt helps with natural snow shedding.
• The region experiences a rainy season (typically June-July), which can reduce solar generation. Using high-efficiency panels with better low-light performance can help mitigate these effects.
• Mountainous terrain in the broader Gifu Prefecture may cause localized shading depending on the specific installation site. Conducting a thorough shade analysis before installation is advisable.

To maximize production despite these challenges, consider using microinverters or power optimizers that minimize the impact of partial shading, implementing regular panel cleaning routines (especially after snowfall), and ensuring proper spacing between panel rows to reduce mutual shading during winter months when the sun is lower in the sky.

Overall, Nakatsugawa provides a reasonable location for solar PV installations, with strong performance during spring and summer that helps offset the reduced winter production. The balanced seasonal profile makes it suitable for grid-connected systems that can utilize the higher summer production while supplementing with grid power during lower-production winter months.

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 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 Nakatsugawa

Seasonal solar PV output for Latitude: 35.485, Longitude: 137.4998 (Nakatsugawa, 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 32° South in Nakatsugawa, Japan

To maximize your solar PV system's energy output in Nakatsugawa, Japan (Lat/Long 35.485, 137.4998) 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 Nakatsugawa, 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 Nakatsugawa, Japan. 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
20° South in Summer	41° South in Autumn	50° South in Winter	29° 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 Nakatsugawa, 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 Nakatsugawa, 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 Nakatsugawa, Japan

Topography of Nakatsugawa

Nakatsugawa is situated in a mountainous region of central Japan, specifically in Gifu Prefecture. The terrain is characterized by rolling hills, steep mountains, and river valleys that create a diverse and complex landscape. The city sits at an elevation of approximately 400-500 meters above sea level, nestled within the southern reaches of the Japanese Alps. The topographical features around Nakatsugawa are largely defined by the Kiso River valley, with mountains rising on multiple sides. To the east lie the Ena Mountains, while the western horizon is dominated by the Central Alps (Chūō Alps). This creates a somewhat enclosed basin-like setting for the city itself, with higher elevations surrounding the central urban area. The landscape includes numerous smaller valleys and waterways that have carved their paths through the mountains over millennia. Dense forests cover many of the mountain slopes, particularly at higher elevations, while the lower areas and gentler slopes have historically been converted to agricultural use or urban development.

Solar PV Potential in the Region

For large-scale solar photovoltaic installations, several factors must be considered when evaluating the Nakatsugawa region. The mountainous topography presents both challenges and opportunities. The most suitable areas for large-scale solar PV development would be: The broader, flatter valley floors, particularly in areas south and southeast of the city center where the terrain opens up somewhat. These locations offer more consistent exposure to sunlight throughout the day without significant shadowing from mountains. South-facing mountain slopes with moderate inclines (not too steep) could potentially be utilized for solar installations. These areas benefit from favorable sun angles and reduced shadowing effects compared to other orientations. Areas where forest cover has already been cleared, such as former agricultural land that is no longer in active use, would minimize environmental impact and land conversion costs. The plateaus and gentler ridges between valleys may offer sufficient flat space for solar array deployment while potentially sitting above valley fog that can sometimes accumulate in the lower elevations. Less suitable areas include north-facing slopes, deep valleys with significant shadowing from surrounding mountains, and areas with dense forest coverage that would require extensive clearing. Additionally, areas prone to landslides or with unstable geological conditions would present significant construction and maintenance challenges. The region's precipitation patterns and occasional heavy snowfall in winter months would need to be factored into the design of any solar installation, with adequate structural support to handle potential snow loading on panels.

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.