performance. Improved building-wide heat-insulating performance would be beneficial not only in terms of energy saving but also in terms of the comfort of the people inside, since it would reduce a temperature gap between room air and the surfaces of floors, walls or ceilings. Such improved insulation could be obtained all the more effectively through the introduction of advanced material technology, component technology, design technology and construction technology.

Rooftop greening and wall greening are also effective for moderating the heat, as they improve light-shielding performance and insulation and have the effect of the transpiration of plants, resulting in a decrease in radiant temperatures of a building. Actually, those greenings have been increasing recently, with the support of various technology developments, including light-weight soils, automated water supply systems, etc. Also, rooftop and wall greenings are expected to enhance $ CO_{2} $ absorptions.

### f. Technologies for motor vehicles

About 90% of transport-attributed $ CO_{2} $ emissions come from motor vehicles. In order to reduce those $ CO_{2} $ emissions, it is important to introduce various measures integrally, including transportation-demand management efforts to control or reduce automobile traffics, promotion of a modal shift for better traffic management (“modal shift” means a shift from road transportation

Figure 3-4-16: Mechanism of a hybrid vehicle

Source: NEDO (New Energy and Industrial Technology Development Organization)

## Column : ESCO (Energy Service Company)

The ESCO program, which represents one of the emerging business models, has been launched and expanding. An ESCO project offers energy-saving services to clients, such as building owners; and saved energy expenses or cut utility costs, which result from the project implementation, will be appropriated for payment (remuneration) to the project operator, future ESCO project expenses, etc. This mechanism allows building owners to introduce energy-saving measures without paying extra money and while enjoying continuing cost reduction after the completion of payment to the project operator.

The ESCO program effectively supports the comprehensive implementation of various energy-saving measures. In this respect, this business model is a “technology” that uses the wisdom of achieving energy savings in a profitable manner. Implementation of ESCO projects makes it possible to promote comprehensive energy-saving measures including the introduction of various energy-saving equipment and systems, BEMS-utilized monitoring practices and efficient operation controls.

Households used to be outside the scope of the ESCO program, since energy-saving achievements obtainable from individual households are so small in size that they could not pay as a profitable business. However, the Ministry of the Environment received a noteworthy proposal from Biwako Bank and others who were entries in the Ministry-sponsored competition program for environmental policy measures (http://www.env.go.jp/press/press.php?serial=7992). The proposal suggests the use of the ESCO scheme for the introduction of preferential interest rates for consumer loans that would encourage private citizens to buy on credit energy-saving latest-model electric appliances to replace their conventional machines. This proposal, titled “Promotion of energy saving at households under the home-version ESCO scheme through multilateral cooperation,” received an award in the competition. Thus, it is expected that private enterprises will play more important roles in promoting $ CO_{2} $ emission reduction in the residential sector in the future.