## Eco-Renovation of Schools

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In addition to being places of education, schools are important centers for promoting global warming mitigation measures, since they are the nucleus of communities. Recognizing this, the Ministry of the Environment began implementing in FY2005 the “School Eco-Renovation and Environmental Education Program” to control carbon dioxide emissions of schools while maintaining a comfortable learning environment for students. The program is carried out with an effective combination of improving insulation to reduce the burden of heating and cooling, introducing renewable energy sources, including solar power generation, and promoting green roofs. This program is characterized not only by the equipment prepared but also by the use of this improvement process as material to develop community-wide environmental education focused on the schools and to disperse technology for environmental construction in the community.

The first eco-renovation project was at the Kuromatsunai Junior High School in Kuromatsunai-cho, Suttsu-gun, Hokkaido completed in February

ber of persons per household and energy consumption shows that per-capita energy consumption increases substantially as the number of persons in the household decreases. A one-person household is said to consume 1.5 times the per-capita energy of a four-person household (Figure 2-2-9). Members of a household generally share 2007. It is estimated that there is a 30% reduction of carbon dioxide emissions from the levels generated prior to the renovation resulting from the use of Galvalue $ ^{\circledR} $ steel sheeting and external insulation methods, afternoon sunlight from the double-paned insulated roof, resin sashes, and wood for the interior, such as beech tree flooring, as well as improvement of lighting efficiency.

Hikari-no-michi (Light Path): Natural sunlight floods the Hokkaido Kuromatsunai Junior High School

(Photo: Courtesy of Atelier BNK Co., Ltd.; Photo taken by Makoto Yoshida)

household electrical appliances, such as hot-water apparatus, refrigerator, and washing machine; the fewer the number of persons in the household, the higher per-capita energy consumption becomes. Such change in Japan’s family structure is a major cause for the increase in energy consumption from using household electrical appliances.

## 4 Residential Energy Consumption and Carbon Dioxide Emissions from Different Energy Sources

Next, let us look at residential energy consumption from the difference in energy sources.

According to IEA statistics data, a comparison of Japan, the United Kingdom, Germany, and the United States shows that the current carbon intensities (carbon dioxide emission per unit of energy consumption) of these countries are at similar levels (Figure 2-2-10). Changes in carbon intensity over time show that Japan's dependence on oil for electricity became lower after the oil crises. The promotion of nuclear energy, natural gas, and other energy sources to replace oil has reduced Japan's carbon dioxide emission intensity of electricity to a low level, even on an international scale (Figure 2-2-11). Although the carbon intensity has become lower concurrently, the decrease has leveled off in recent years.

In Japan, the residential energy sources in 2005 include 52% of electricity, 29% petroleum, 17% gas, and 1% solar energy. Compared to the energy consumption of each of the energy sources in 1990, consumption of energy from electricity increased by 81%, gas 27%, and petroleum 18% (Figure 2-2-12). Compared to the United Kingdom, Germany, and other countries, Japan uses a much larger percentage of energy from electricity. For this reason, compared to the other countries, an increase or a decrease in the carbon dioxide emission intensity of electricity due to the changes in the composition of fuels