The underuse of agricultural land in rural areas is an arising issue in Japan that could lead to the loss of biodiversity, unique culture and tradition linked to agricultural activities, and economic gains that the agricultural sector generates. Our newly published article Assessment of alternative land resource utilisation towards Net-Zero and regional revitalisation through the circulating and ecological sphere in depopulated city regions in Japan: a case study of Hachinohe City Region focuses on how such land could be utilised for Net-Zero and local benefits.
What is the Circulating and Ecological Sphere?
A key concept used in this study is the Circulating and Ecological Sphere (CES) introduced by the Japanese government to promote a self-reliant decentralised society where local areas support one another with the resources they have to offer (Ministry of the Environment 2018; Takeuchi et al. 2019). We considered the underutilised agricultural land as a local resource and decided to explore how a CES may be implemented.
We conducted a study in the Hachinohe City Region, which is an area experiencing an increase of abandoned land largely due to the continuous population decline and ageing of agricultural sector workers. Understanding these local challenges was essential because our intention was to explore how the underutilised land could be re-purposed in ways that not only contribute to decarbonisation but also address other social or economic local issues causing the increase of underutilised land.
What if the underutilised lands are used to produce renewable energy?
Two scenarios of potential utilisation are developed: an energy-dominant scenario and an agriculture-energy combination scenario. The former assumes the land to be converted as solar energy generation sites (i.e., installing solar panels) and the latter to be used for agrivoltaics, whereby solar panels are installed on agricultural land while farming activities continue underneath them.
For each scenario, we calculated numerous factors, including the amount of solar electricity generated and consumed, total CO2 emissions, and the number of jobs created. For the agriculture-energy scenario, total food production was also estimated.
To sum up the results of these calculations, we found that roughly 2,200-2,900 GWh of electricity can be generated from solar energy by using abandoned land. As this covers over 100% of electricity consumption in the region, thiscan make the direct CO2 emission from electricity generation fall to zero, which could reduce the regional per capita carbon emission by about 2 tons. Around 6,300-8,400 jobs could be created via the alternative uses, which aligns with, for example, the region’s core city Hachinohe city’s policies to support and invite in-migrants into the city. Regarding the potential amount of food produced, the calculation estimates the production of 21 million kg of rice. Although the prefecture the region belongs to has over 100% food sufficiency, this result indicates that this surplus could be redistributed to bigger urban areas, thus contributing to national food security all the while reducing environmental pressures from making long-distance imports.
To maximise the potential of these alternative land uses, we suggested three policy interventions in this article.
- First, collaboration amongst the members of the Hachinohe City Region is necessary as not all member municipalities can, on their own, achieve carbon neutrality. Collaborations with areas that have sufficient renewable electricity generation potential could supplement their shortfalls.
- Investment is needed for those areas that do not have the transmission lines necessary to utilise their resources. One possibility for them would be to work with larger cities (e.g., cities in the Tokyo metropolitan area) with high electricity demand and an ambitious target to become a Net-Zero city.
- Lastly, national or local governments may support local energy cooperatives to make renewable energy production beneficial for local people. Regional resources would not be beneficial for the local communities if they were used and managed only by external entities.
It is our understanding that this assessment presents alternative future scenarios where current environmental and other local issues are dealt with. Going forward, further studies are hoped to ensure that the alternative land use scenarios will be implemented and deliver beneficial outcomes for the path towards Net-Zero and local communities.