Special

Vehicle-type Grass Cutter Employed for 1.86MW Solar Plant in Fukuoka (1)

Even grass under arrays can be efficiently cut

2017/09/13 16:21
Shinichi Kato, Nikkei BP Intelligence Group, CleanTech Institute
Print Page

Grass control is a challenge that mega (large-scale) solar power plant operators always face for a long period during power generation. The growth speed of grass and measures to be taken vary depending on the location of the site, and there is no total solution at present.

Grass grows rapidly on the sites of mega solar power plants developed near farmland. Fertile land with abundant sunlight is suitable for farming. Land with abundant sunlight is suitable for solar power generation, but grass takes root and grows easily on fertile and sunny land.

At present, grass cutters are most frequently used at domestic mega solar power plants as measures against grass. Grass is cut periodically when it grows to a certain height. Grass dies in winter, and grass cutting is normally done two or three times during the period from spring to autumn every year.

The physical load on persons who cut grass increases in line with the increase of the area. Grass grows rapidly in summer when the temperature and humidity are high, and the physical load expands when grass cutting is done in the daytime in such season.

As measures to reduce the physical load on persons who cut grass and improve the efficiency, riding-type grass cutters are now more widely used. The operator rides on a four-wheel vehicle similar to a go-cart and drives the vehicle on the site. Grass is cut by a rotary blade under the vehicle's seat.

Unlike carrying-type grass cutters that were generally used, the operators do not have to walk around the site moving the cutting blades from side to side. Therefore, the physical load on the operators is reduced. The operation time is also decreased because the time per area is shorter than before.

This is a report on a mega solar power plant adjacent to rice fields in the Kyushu region. The operation was streamlined by using riding-type grass cutters, while incorporating suitable designs and layout for the power generation equipment (Fig. 1).

Fig. 1: Grass cutting at the "Miyama Takata Power Plant" with about 1.86MW output. The grass was cut by two riding-type grass cutters. (source: Nikkei BP)