## 3 Results and Discussion
### Discussion  
This study used annual global market growth rates for each product to estimate demand for plastics, dry ice, and sulfur. The annual growth rates for these products in the Japanese market might differ from those in the world market. In addition, the growth rates might not remain the same until 2050, and the estimates are rough. This is also similar for the estimation of the supply of each of these products. Nevertheless, the fact that estimates were able to show that the output gap for these products would be large enough to achieve the 1.5 \({}^{\circ}\)C target is a significant contribution. Regarding plastic products, a very large discrepancy between the supply and demand of plastic resins became evident as the 1.5 \({}^{\circ}\)C target was achieved. In accordance with the Plastic Resource Circulation Act, the Japanese government is required to promote the recycling of plastic waste. Figure 3 indicates that the recycling rate of plastic waste in 2019 was 85%, and most plastic waste was already being used effectively [34]. However, energy recovery, which accounts for approximately 60%, is integrated into the recycling process. By converting waste plastics that have been energy recovered, incierated, and landfilled to mechanical recycling, the achievement of the milestone in 2030 set by JMOE [39] doubles the recycling of waste plastic from 910.00 thousand ton in 2019 to 1800.00 thousand ton in 2030. However, the national government should discuss the increased labor and infrastructure costs for transporting, sorting, and cleaning waste plastics to achieve this [45]. In addition, the introduction of 2000.00 thousand ton of biomass plastic, which JMOE [39] set as a milestone for 2030, is extremely difficult considering that the production volume was only 45.00 thousand ton in 2018 [46]. Biomass plastics are 1.5 times more expensive than polyethylene made from fossil fuels, and the price difference is an obstacle to the spread of biomass plastics [47]. For biomass plastics to have the same competitiveness as fossil-fuel-based plastics, national government should take the initiative to ensure a stable biomass supply as raw materials, reduce costs through mass production, and tax fossil-fuel-based plastics. Regarding hydrogen, the Japanese government has positioned hydrogen as an important energy source. They have been jointly developing technologies related to the construction of fuel cell vehicles and hydrogen energy infrastructures [4]. According to the New Energy and Industrial Technology Development Organization (NEDO) [48], if hydrogen power generation becomes a reality, domestic hydrogen demand in 2030 is expected to rise to 2.2 billion Nm\({}^{3}\). According to the results of this study, 1.53 billion Nm\({}^{3}\) is expected  
Figure 6: Outlook of supply and demand volume of sulfur production. to be available in 2030, and hydrogen production associated with petroleum refining could be one way to ensure supply against demand. However, hydrogen production declines as the 1.5 \({}^{\circ}\)C target is achieved, so hydrogen production is not expected to be a permanent energy source. Regarding dry ice, one measure to solve the output gap is to increase the import volume of dry ice. However, imports not only incur higher transportation costs than domestic production but also depend on the production situation of exporting countries such as South Korea [49]. If the exporting countries were making efforts to achieve the 1.5 \({}^{\circ}\)C target, the production volume of the dry ice that Japan imports would also be expected to reduce accordingly. Other measures include installing new equipment to produce dry ice from low-concentration carbon dioxide, and storage equipment to stabilize the supply. However, this also incurs the cost of expanding the facilities, and the current situation cannot achieve the current demand for dry ice. This result reveals that dry ice is one of the products that have a great social and economic impact due to the reduction in petroleum consumption.