Standard Design for Agrivoltaics in Japan

Fujidana style and array designs are the most common types of solar sharing in Japan. In the case of the Fujidata style, which can equalize the amount of solar radiation to crops, a shading ratio of about 40% can be considered as a standard design.

Fujidata style in Japan

The number of solar panels that can be installed with a shading ratio of 40% is about 1,800 per hectare of farmland.

As of 2021, solar panels with an output of around 450W are the mainstream, so 810kWp is the output of solar power generation.

Depending on the region where it is installed, it can be expected to generate 900,000 to 1,000,000 kWh of electricity per year.

Since the current unit price for electricity sales under Japan's FIT is 11 yen/kWh, we estimate that the annual income from electricity sales will be between 10 million yen and 11 million yen.

On the other hand, the annual sales of crops in a paddy field of the same size will be about 1 million yen, while in a field it will be 3 to 5 million yen.

Working with tractors

The distance between the pillars should be about 4 to 5 meters, and the overall height of the facility is designed to be about 4 meters. By doing so, we aim to secure the working space for agricultural machinery and solar radiation from scattered light.

Leafy Vegetables and Agrivoltaics

One of the characteristic agricultural products grown under agrivoltaics is leafy vegetables such as cabbage and lettuce. 

Since they are easily affected by strong sunlight, shading with solar panels will help the growth of leafy vegetables.

Growing Cabbage and Lettuce

In the lowlands of Japan, summers are too hot for growing leafy vegetables. However, solar sharing makes it possible to grow leafy vegetables by blocking the strong summer sunlight.

Another known benefit of the presence of solar panels is that they help to control frost in winter. Therefore, in areas where leafy vegetables could not be grown in the winter, it has become possible to grow cabbage and other crops through solar sharing.

Of course, it's not just good for leafy greens. Shading by solar panels delays the drying of the ground after rain. This can lead to disease outbreaks due to moisture damage.

Nevertheless, the advantage of being able to grow vegetables that could not be grown within the region before will bring about a very significant change.