power which is generated in the stations is provided back into public facilities around them. This is a system which can use renewable energy efficiently.

Toyota City gives a high priority to the spread of PV and PHV. Subsidies for eco-friendly vehicles and free use of charger stations are examples of these efforts. Toyota City is going to launch a subsidy for introducing household chargers in 2012.

In addition, Toyota City is trying to introduce a smart grid: connection of electric systems between houses and PHVs, generating electricity by photovoltaic cells and charging a storage battery, and utilizing electricity in the storage battery as an emergency power source.

In a mid-sized city area, the charger facilities can be successful in a practice under a well-managed plan for introducing next generation vehicles and charger stations with renewable energy.

(3) Initiatives in Small Cities, Towns, and Villages (Shimokawa Town, Hokkaido)

In recent years, the depopulation of hilly and mountainous regions has led to depressed regional vitality. However, these regions are rich in natural resources, such as forest resources and water resources, which are hard to come by in urban areas. There are a number of examples of initiatives in small cities, towns, and villages seeking energy independence through actively and efficiently utilizing local renewable natural resources, such as biomass resources, small and medium-sized hydro power, and solar and wind power.

Shimokawa Town in Hokkaido is famous throughout Japan as a forestry area. The government, the forestry industry, its stakeholders, and the community residents are working together to implement an action plan that seeks to promote sustainable forest management, zero carbon emissions timber processing, and effective utilization of the biomass resources obtained from this process (Figure 3-4-3).

Shimokawa is a cold, snowy region, which tends to rely on fossil fuels for heating. Given this fact, an active effort is being made to use biomass resources for heating, thereby reducing carbon dioxide emissions. For example, a system is being introduced which uses forest thinnings and leftover pieces of cut lumber as fuel for a wood furnace installed in the town office, and the heat produced by this furnace is then supplied to surrounding public facilities. In addition, the town is encouraging residents to install wood furnaces in their homes and is working on cultivating basket willows (which reach maturity in a short period of time) for use as an energy crop for these wood furnaces and the like. Also, logging offcuts from forest thinning and other forestry activities, as well as trees cleared from sites such as river

Figure 3-4-1 Efforts for Introduction of EV and PHV in Toyota City

☑The chargers for EV and PHV in the City

Source : Toyota City

☑A charger with photovoltaic panel

Figure 3-4-3 Biomass Utilization in Shimokawa Town

Source: Shimokawa Town

and forest paths, are collected at a facility that uses them to manufacture and supply wood waste fuel for use in wood furnaces. Thus, this woody raw material production center makes effective use of underutilized woody biomass resources.

It is hoped that comprehensive utilization of biomass resources in areas that are rich in them, together with the promotion of cooperation between residents, the government, and private business in forest development, will foster the creation of next-generation, low-carbon model societies that exist in harmony with the forests of northern Japan, contributing to local industry while reducing carbon dioxide emissions.

## 2 Establishing Self-Relient Local Community

## (1) Efficient Network System for Electricity Supply and Demand

Renewable energy such as photovoltaic and wind power depend on the natural conditions, so it is necessary to establish the integrated system on both the supply-side and demand-side including buck up generators and electricity storage systems in the case of mass introduction of renewable energy. The smart grid system is expected to overcome this issue since it can manage and control both sides, especially the demand-side which is difficult to manage, by utilizing Information Technology and electricity storage systems. Smart community expands the functions of the smart grid and it includes not only electricity systems but also heat and transportation systems. Such integrated systems are drawing attention recently to realize the security of energy supply and efficient use of electricity.

output is approximately 180 GJ per hour. The combined energy efficiency for the electrical and heat supply is 75%, which is better than even a large thermal power plant, and this electricity and heat is supplied continually throughout Roppongi Hills' facilities.

During the Great East Japan Earthquake, when the Tokyo metropolitan area faced a severe power shortage due to damaged nuclear reactors, this system was completely unaffected thanks to the fact that it uses gas for fuel. Not only was the system able to support the energy needs of Roppongi Hills, but also, during the power crunches Tokyo experienced from March to April and July to September

## (2) Establishing Self-Relient Local Community with Gas Co-generation

During the redevelopment of Roppongi Hills in Tokyo’s Minato Ward, a co-generation system was installed that utilizes city gas (medium pressure). This system provides Roppongi Hills with tremendous energy efficiency and energy independence. As part of a concept to develop “a city to run to in times of disaster,” seven state-of-the-art gas turbine-type co-generation systems have been installed. Electrical generating capacity is 38,660 kW; cold energy output is approximately 240 GJ per hour; and hot energy

Source : The Japan Gas Association