Sakamachi, Japan, located at latitude 35.7003 and longitude 139.7144 in the Northern Temperate Zone, offers reasonably good conditions for solar PV energy generation throughout the year, though with notable seasonal variations.

Seasonal Solar Production

The location experiences significant differences in solar energy production across the four seasons. Summer is the most productive period, generating approximately 5.27 kWh per day for each kilowatt of installed solar capacity. Spring follows closely behind with 5.22 kWh/day. The cooler seasons show a marked decrease, with autumn producing 3.56 kWh/day and winter slightly less at 3.44 kWh/day.

This pattern creates a bimodal production curve with peaks in summer and spring, and lower output during autumn and winter months. The difference between the highest and lowest producing seasons is substantial, with summer generating about 53% more electricity than winter.

Optimal Panel Installation

For fixed solar panel installations in Sakamachi, the ideal tilt angle to maximize year-round energy production is 33 degrees facing South. This angle has been calculated to optimize the annual solar harvest by accounting for the Earth's elliptical orbit and the location's specific latitude.

Environmental and Weather Considerations

Several factors could potentially impact solar production at this location:

• Seasonal rainfall and humidity, particularly during Japan's rainy season (typically June-July), which can reduce solar efficiency
• Occasional typhoons that may bring extended periods of cloud cover
• Winter snowfall that could temporarily cover panels
• Urban air pollution, as this appears to be in the greater Tokyo area, which can diminish solar irradiance

Preventative Measures

To maximize solar production despite these challenges, several preventative measures can be implemented:

• Install panels with self-cleaning hydrophobic coatings to minimize the impact of rain and pollution
• Use a slightly steeper tilt angle than the optimal 33 degrees if winter snow accumulation is a significant concern
• Implement regular maintenance schedules, particularly before and after the rainy season
• Consider microinverter or power optimizer technology to minimize the impact of partial shading from nearby buildings or structures
• Install robust mounting systems designed to withstand typhoon-force winds

With proper installation and maintenance, Sakamachi's location can provide efficient solar energy generation, particularly taking advantage of the highly productive spring and summer months to offset the reduced output during autumn and winter.

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 Sakamachi

Seasonal solar PV output for Latitude: 35.7003, Longitude: 139.7144 (Sakamachi, 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 33° South in Sakamachi, Japan

To maximize your solar PV system's energy output in Sakamachi, Japan (Lat/Long 35.7003, 139.7144) throughout the year, you should tilt your panels at an angle of 33° 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 Sakamachi, 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 Sakamachi, Japan. As mentioned earlier, for fixed-panel solar PV installations, it is optimal to maintain a 33° 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 Sakamachi, 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 Sakamachi, 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 Sakamachi, Japan

Sakamachi is situated in the heart of Tokyo, Japan, specifically in the Toshima ward. The topography of this area is predominantly characterized by urban development on relatively flat terrain. This location sits within the Kanto Plain, one of Japan's largest flat areas, which has undergone extensive urbanization over centuries. The natural landscape has been largely transformed by human settlement, with buildings, roads, and infrastructure replacing much of the original topography. The broader region around Sakamachi features subtle variations in elevation. Moving eastward, the terrain gradually descends toward Tokyo Bay, while westward, the land begins to rise toward the mountainous regions that surround the Kanto Plain. Despite being in a densely populated urban center, the area's original geography was shaped by river systems, including the nearby Sumida River, which has influenced settlement patterns throughout Tokyo's history.

Surrounding Geographical Features

While Sakamachi itself is predominantly flat urban terrain, the greater Tokyo region exhibits more varied topography. To the west lie the Okutama Mountains, part of the larger Kanto Mountain Range, creating a natural boundary. These mountains, though not immediately adjacent to Sakamachi, influence the broader regional climate and historically served as a natural barrier that helped shape Tokyo's development patterns. To the east, the flat Kanto Plain extends toward Tokyo Bay, with much of this area heavily developed. The original landscape featured numerous small rivers and streams that have been modified, channelized, or built over during urban development. The natural drainage patterns have been largely replaced by engineered water management systems throughout the metropolitan area.

Potential Areas for Solar PV Development

For large-scale solar photovoltaic (PV) development near Sakamachi, several geographical considerations must be taken into account. The urban nature of Sakamachi itself makes it unsuitable for large ground-mounted solar arrays due to the scarcity and high cost of land. However, the broader region offers some possibilities: The rooftops of large commercial and industrial buildings throughout Tokyo represent the most practical nearby spaces for solar development. These flat surfaces provide significant square footage without requiring additional land use. While not traditionally considered "large-scale" in the sense of dedicated solar farms, the aggregate potential across Tokyo's vast building stock is substantial. Moving further from Sakamachi, the northern and western outskirts of Tokyo, where population density decreases and more open land becomes available, offer better opportunities for larger installations. Areas in neighboring Saitama Prefecture, particularly former agricultural lands that have fallen into disuse, could be repurposed for solar development. The most promising locations for truly large-scale solar PV would be even further from Sakamachi, in regions like Chiba Prefecture to the east or parts of Kanagawa Prefecture to the south. These areas feature more available land, fewer tall buildings causing shading issues, and greater distance from the densest urban development. Former industrial zones or brownfield sites in these regions could be particularly suitable for redevelopment as solar facilities. The mountainous regions to the west, while offering less competition for land use, present challenges for solar development due to their steep slopes, forest coverage, and potential environmental impacts. These areas would generally be less suitable despite having lower population density.

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.