79MW Solar Plant Achieves Utilization Rate of 17.6% in Tohoku (page 3)
2x areal efficiency, 1.6x overloading by setting up more than 1MW per 1ha
Areal efficiency doubled from normal level
In terms of mega-solar plants in Japan, it is generally said "nearly 2ha is required to set up solar panels equivalent to 1MW." For example, at the "Minamisoma Mano Migita Ebi Solar Power Plant," which also began operation in a tsunami-affected area just like the Watari Solar Power Plant, panels equivalent to about 60MW were set up on the approximately 100ha site.
At the Watari Solar Power Plant, on the other hand, solar panels equivalent to about 80MW were set up on the approximately 75ha site. The areal unit per 1MW of solar panels is less than 1ha, resulting in about double the areal efficiency per panel capacity at other solar plants.
Yamasa realized this through such efforts as solar panel array (unit of panel installation) structure and installation angle as well as the space between arrays.
Basically, at this plant, large-area arrays consisting of 12 sideways panels in 8 rows were tilted by 10° and mounted on pile foundations with the lowest part of each array's front side set up at 1.3m from the ground. In addition, the space from the array in front was shortened to about 1.4m (Fig. 5).
At most solar power plants in Japan, each array consisting of sideways panels in four rows is tilted by 10 to 20° and set up at 1 to 1.5m from the ground. The arrays are usually spaced 2 to 3m from each other.