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Mega Solar Plant Uses 3 Panel Angles as Measure Against Snow Cover (2)

2018/10/12 13:00
Shinichi Kato, Nikkei BP Intelligence Group, CleanTech Labo
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Continued from Mega Solar Plant Uses 3 Panel Angles as Measure Against Snow Cover (1)

Snow needs removing every day in Yamagata

The panels of the mega solar power plant in Yamagata Purification Center were installed at various angles, but the height of the bottom is 1m for all the solar panels. The annual average snowfall in the area is approximately 50cm. The company wanted to set the height of the bottom to 1.5m, 1m higher than the average snowfall, but gave up and set the height to 1m because of the cost.

Once it started the operation, the company learned that 1m is an appropriate height. During the snow season, snow is removed nearly every day using snowblowers. The height of 1m is essential for operating the snowblowers without hitting the solar panels; a height exceeding 1m would have been too much.

The company estimates that mega solar power plants in Yamagata Prefecture require snow removal even if the height of the bottoms of the solar panels is elevated as much as possible (Fig. 6).

Fig. 6: Snow on the ground removed frequently by snowblowers. Before removal (left) and after removal (right) (source: Power E Next)

This is because snow removal will become difficult if snow on the ground is left for a long period because snow in Yamagata is comparatively heavy. When consideration is given to operations throughout the season, they are easier to handle if the snow is removed frequently or nearly every day.

Snow removal operations are entrusted to a local sports club and soccer coaches in the club undertake the work. Recently, soccer coaches throughout Japan are becoming professional, and they often sign contracts with sports clubs. But the remuneration is limited in many cases. The sports clubs to which Power E Next entrusts with snow removal operations are in the same situation, and the income from snow removal at mega solar power plants is important to them, according to the company.

Nearly all the customers of the sports club that undertakes snow removal operations of the company are children, and coaches do not give instructions to them during school hours. There is also a lot of free time on holidays and during long vacations. Soccer coaches remove snow from mega solar sites during their free time. The coaches visit the seven mega solar plants of the company every day in pairs.

From spring to autumn, when there is no snow, they remove weed from the sites. They use riding-type weed cutters and strimmers. Riding-type weed cutters are used as much as possible to improve operational efficiency.

The company thinks that measures should be taken so that general management operations, excluding operations that have to be carried out by experts, such as electrical work, can be performed by members of the public without special skills and knowledge. Priority is given to this policy in carrying out snow removal and weed removal in particular.

In some regions and power plants, snow removal and weed removal are entrusted to 'silver' human resources centers and the operations are handled by aged persons. However, such operations are not popular among workers because the physical burden is high. Some 'silver' human resources centers do not handle operations at power plants because of the risk of damage to power generation equipment including cutting of power cables during weed cutting operations.

Power E Next positions snow removal and weed removal operations as opportunities to bring economic effects to the local community while positioning the use of coaches at sports clubs for the operations as an opportunity to contribute to activation of local society. The company expects that the coaching skills of the coaches will develop when the environment and payment are improved, and the local communities will be vitalized by the children for a long period.