With the rapid spread of solar power generation, sediment-related disasters have occurred one after another at facilities installed on slopes in recent years.
Analysis of the locations of medium-sized and larger solar power generation facilities nationwide based on expert data shows that there are more than 1,100 facilities nationwide that partially overlap with "earth and sand disaster risk areas" that are at risk of disaster. I found that it was climbing.
Experts point out that "a mechanism for assessing the risk of disasters and installation in risky areas need to be curtailed."
The solar power generation facilities installed on the slopes have suffered a series of sediment-related disasters in recent years, and according to the Ministry of Economy, Trade and Industry, a total of 11 cases were confirmed due to the heavy rains in western Japan three years ago, and the Sanyo Shinkansen temporarily stopped in Kobe City. There was an influence such as.
NHK analyzed the location data of medium-sized facilities with a power generation output of 500 kilowatts or more and the map data of sediment disaster risk, which were calculated by the National Institute for Environmental Studies from aerial photographs.
As a result, of the 9809 target locations, 10% of the total overlapped with "sediment-related disaster risk areas" where sediment-related disasters could cause damage to houses and public facilities. It turns out that there are at least 1186 places to exceed.
By type, there
are 724 places in the "debris flow danger mountain stream
", 463 places in the "steep slope collapse danger place",
and 77 places in the "landslide danger place".
(There is duplication) In
addition,
there
are 843 facilities that partially overlapped with the "sediment-related disaster warning area" that requires evacuation and other measures, of which 249 are particularly dangerous "sediment-related disaster special warning areas." It overlapped with.
With some exceptions, there is no national law that regulates installation in places where there is a risk of disaster, and the actual regulation is left to the local government.
According to the Research Institute for Local Government, an increasing number of local governments are enacting ordinances on installation regulations, and as of July, there are four prefectures and 148 municipalities.
Professor Takeyasu Suzuki of the Department of Civil Engineering and Environmental Engineering, University of Yamanashi, who specializes in civil engineering, said, "At present, we do not know where the risks are, and there are actually places where the risk of disasters is increasing without the residents' knowledge. In addition to a mechanism for grasping and evaluating risks, it is necessary to urgently put in place safety regulations such as restraining installation in dangerous places. "
In the town where the landslide disaster occurred twice during the construction of the facility
In some towns, two landslides occurred during the construction of a solar power plant.
In Ogose Town, Saitama Prefecture, two sediment-related disasters occurred at the construction site of a solar power generation facility in March and October.
The first time a huge stone fell and blocked the town road.
According to the town, after that, although safety measures were requested from the contractor, construction was resumed without sufficient implementation, and a landslide occurred seven months later.
Although there was no human damage, the town road, which is also a living road, was closed for a week, which had a great impact on the lives of the residents.
This place was designated as a "sediment-related disaster risk area" that could damage houses, but at that time, there were no laws or ordinances prohibiting construction itself at this place because of the risk of sediment-related disasters. did.
A woman living in the immediate vicinity of the facility said, "I'm really worried that it will collapse during a typhoon. At least I want the facility to be safe."
In response to the landslide, the town repeatedly provided administrative guidance to the business operators for countermeasures.
The business operator explained to the residents that measures such as drainage channel maintenance would be carried out by the end of May, but the work has not been completed.
On the other hand, power generation started in late February.
The business operator told NHK that "the company that requested the construction went bankrupt and the countermeasure construction has been postponed. I would like to deal with the residents in good faith."
In response to this disaster, Ogose Town is considering enacting ordinances to regulate the installation of solar power generation, such as setting areas with high risk of disasters such as landslides and debris flows as "control areas". I will.
Mayor Yasuhiki Arai of Ogose Town said, "Although we recognize the need to promote renewable energy, the lives and property of residents are the first priority for the town. National law should be a concrete regulation on the safety of solar power generation facilities. There is a limit to what the town can do. I would like to ask the government to further consider how safety measures should be, such as restricting locations in risky places and strengthening guidance on dangerous facilities. " I'm talking.
Consider excluding areas at risk of national sediment-related disasters from "promotion areas"
Regarding the location of renewable energy such as solar power generation facilities, the national government has decided to apply to municipalities nationwide in order to lead to the smooth introduction of renewable energy in the Global Warming Countermeasures Promotion Law revised in May. We are asking you to specify a "promotion area".
In the background, there are cases where residents are having trouble with construction, etc., so we have a policy of excluding places that affect the conservation of the natural environment.
However, in recent years, there have been a series of voices of anxiety about disasters and locations at solar power generation facilities, etc. ..
However, even if it is not designated as a "promotion area" because of the risk of sediment-related disasters, it does not mean that the construction of solar power generation facilities will be regulated.
A series of local governments enacting installation regulation regulations
In response to disasters and troubles surrounding solar power generation facilities, a number of local governments are enacting ordinances to regulate installation.
According to the Research Institute for Local Government, which conducts surveys and research on local administration, the ordinances that regulate the installation of solar power generation facilities began to be enacted by local governments around 2014, and as of 13th of this month. It means that there are 4 prefectures and 148 municipalities.
Of these, three prefectures, which are three-quarters, and 110 municipalities have enacted ordinances since 2018, which means that they have increased rapidly in the last few years.
The content of the regulation varies depending on the local government, but there are those that set up areas that prohibit or suppress the installation, those that require notification and local consent at the time of installation, and fines and fines for businesses that do not obey the orders of the local government. There are things that ask for.
Facility near Atami debris flow site Shizuoka Prefecture "No direct relationship"
A debris flow occurred in Atami City, Shizuoka Prefecture this month, but there was a solar power generation facility near the collapsed embankment.
According to a survey conducted by Shizuoka Prefecture, no collapse of the surrounding slopes was confirmed, and "there is no direct relationship with the debris flow."
On the other hand, in response to this debris flow, some other local governments have begun urgent inspections because it is necessary to understand the risk of sediment-related disasters associated with development activities at power generation facilities.