Solar Panels: Promote Decarbonization through Thorough Recycling

To realize a decarbonized society, it is essential to further promote the use of solar power, but the problem is what to do with aging solar panels.

The government should promote recycling of the panels and at the same time work on innovations in related technologies.

The Economy, Trade and Industry Ministry and the Environment Ministry have jointly set up a panel of experts to discuss making the recycling of solar panels compulsory. The ministries reportedly plan to submit related bills to the ordinary Diet session next year.

Solar power generation expanded rapidly after the Great East Japan Earthquake. In fiscal 2011, solar power accounted for only 0.4% of the power supply, but this figure had increased significantly to 9.2% by fiscal 2022.

The government has set a target of raising the figure to between 14% and 16% by fiscal 2030. The broad use of solar power is essential to achieving the nation’s international commitment to reduce greenhouse gas emissions to net-zero by 2050.

The service life of a solar panel is said to be around 20 years to 30 years. As a result of the large number of panels installed over the past decade or so, there is a possibility that up to 500,000 tons of panels will be disposed of each year from the mid-2030s onward.

To expand solar power generation without burdening the environment, it is critical to promote the recycling of solar panels. However, most used panels are disposed of in landfills, and these resources are not being used effectively.

Another problem is that damaged power generation facilities are not being revamped and are being left unrepaired in many places around the country.

Currently, the recycling of solar panels is left to the voluntary efforts of the private sector, but since it is cheaper to dispose of them, there has been little progress on recycling them.

To change this, recycling will have to be made mandatory, even if that means power companies will have to bear some of the cost. It is important that the government consider penalties for power companies to encourage recycling, among other measures.

Tracking the recycling process, such as by putting identification numbers on the panels, could also be effective. In addition, the public and private sectors will need to work together to develop technology for low-cost recycling.

There is also an urgent need to develop high-performance batteries. Since the amount of power generated by solar panels varies depending on the weather, any shortfalls will need to be made up for with thermal power. On the other hand, there is often an excess of electricity when the weather is good.

If the capacity for storing electricity increases, it will become possible to store large amounts of electricity generated from renewable energy.

There are also high hopes for perovskite solar cells, a technology developed in Japan. These cells are lightweight and thin, and can be bent, allowing them to be installed on the walls of buildings and the roofs of vehicles. In Japan, where there is little flat land, the cells could play a key role in decarbonization.

(From The Yomiuri Shimbun, Oct.1, 2024)