Objective. The recent Carbon Footprint of Products (CFP) program puts an emphasis on communicating with consumers and can be used to indicate Life Cycle CO₂ emissions (LC-CO₂) of products. Under the program, suppliers offer LC-CO₂ information for their own products, and then consumers can act in an environmentally conscious way based on that information. We calculated LC-CO₂ emissions for three representative restaurant menus (serving Japanese, American, and Chinese-style dishes), based on cost accounting data provided by Skylark Co., Ltd., information from the CFP database, and 3EID. Our objective is to show that Skylark's cost accounting data has the potential to calculate LC-CO₂ indicators, which can be helpful for environmentally conscious consumers.
Results and Discussion. Per-serving LC-CO₂ indicators of representative restaurants' menu were 2,637g-CO₂ for Japanese-style dishes, 4,080g-CO₂ for American-style dishes, and 1,742g-CO₂ for Chinese-style dishes. Comparing CO₂ emissions per serving between restaurant dishes and homemade dishes shows that there is a difference in emission structures. By clarifying those structures, consumers become better able to understand the route of CO₂ emissions and to control them. We evaluated the CO₂ emissions of restaurant customers through the use of a questionnaire which asked respondents which style of dishes they tended to choose, and which method of transportation they used when visiting restaurants. The results showed that consumers who prefer Japanese-style dishes generated low CO₂ emissions per serving. When a consumer used a personal vehicle to get to the restaurant, it generated about the same CO₂ emission as the dish which the consumer ordered. The specific CO₂ emissions per serving can be lowered either by reducing energy input and waste discharge in restaurant operations or by reducing the use of vehicles.
Conclusions. Our research shows that we can estimate useful indicators of LC-CO₂ emissions from restaurant dishes by using corporate accounting data. This data must be complemented with information from secondary databases, but we can derive a lot of useful information for both consumers and important policies. As this type of accounting data is regularly tallied and collected as part of daily company operations, using such data for LC-CO₂ indicators per serving could potentially contribute to the construction and diffusion of CFP program without adding any additional costs.