TOEFL統合ライティング

📖 読解文章

The use of biofuels, such as ethanol derived from corn, has been promoted as a sustainable alternative to fossil fuels. Proponents argue that biofuels offer three major environmental and economic benefits. First, biofuels are considered carbon-neutral because the carbon dioxide emitted during combustion is roughly equivalent to the amount absorbed by the plants during their growth. This cycle is thought to mitigate global warming. Second, biofuels reduce dependence on foreign oil, enhancing national energy security. By producing fuel domestically from agricultural crops, countries can lessen their vulnerability to volatile global oil markets. Third, the biofuel industry stimulates rural economies by creating new markets for agricultural products. Farmers can sell crops like corn at higher prices, and the construction and operation of biofuel plants generate jobs in rural areas, thereby boosting local economic development.

🎧 リスニング講義

The lecture challenges the claims made in the reading about biofuels. While the reading asserts that biofuels are carbon-neutral, the professor points out that this is misleading. The production of biofuels requires significant energy inputs—for planting, fertilizing, harvesting, and processing—most of which come from fossil fuels. When these indirect emissions are accounted for, biofuels may emit as much or even more greenhouse gases than conventional gasoline. As for energy security, the professor explains that relying on crops for fuel can create new dependencies, such as on fertilizers, pesticides, and agricultural technology, often imported from other countries. Moreover, diverting land to biofuel crops can reduce the production of food, forcing nations to import more food, which undermines energy security rather than enhancing it. Finally, the economic benefits to rural communities are overstated. Government subsidies and mandates often inflate crop prices, benefiting large agribusinesses, not small farmers. Additionally, the jobs created by biofuel plants are often temporary and require specialized skills, so local workers may not fill them, and the long-term economic gains are limited.