平湯 直子

Objective. The purpose of this research is to compute the CO₂ emissions during the sales process of foods, and to offer information convenient for consumers. Using operating data offered by 8 stores, we calculated the CO₂ emissions for each food and store from electricity and gas use, waste disposal, plastic tray production, resource waste material recycling, customer automobile use, and the amount of recyclable waste collected from customers.<BR>Results and Discussion. The main CO₂ emission factors during the sales process of goods are supermarket electricity and gas use and customer automobile use. The amounts depend on the characteristics of the store in which the foods are sold, for example, the area of the store, the sales numbers per unit area, the distance from the store to the closest station, the percentage of customers from surrounding neighborhoods, average customer spend, age-group of main customers. At present the CO₂ reduction effect by recycling of resource waste material is relatively small. According to our simulation analysis, electricity and gas-saving measures through energy management contributes greatly to the reduction of CO₂ emitted during the sales process of goods.<BR>Conclusions. To reduce CO₂ emission during sales process, it is important for the store to take measures to reduce consumption of both electricity and gas, and to control the extent of customer automobile usage. If consumers know CO₂ emission factors as well as stores' managers, they can understand what they must do. It's desirable to make the information of CO₂ emissions during the sales process as best we are able. This paper shows an example of such information. This research clearly shows that the operating data companies collect daily can be very useful in calculating CO₂ emitted during the sales process of goods.

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.<BR>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.<BR>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.