**1. Introduction**

As global warming becomes more serious, development of a low-carbon society has become an urgent task [1–3]. In particular, reduction of the energy used to cool and heat buildings, which is a large portion of energy usage during summer and winter, is an important issue [4, 5]. However, CO2 emission due to heating and cooling-related energy consumption is still increasing. Thus, practical measures are needed to reduce CO<sup>2</sup> emissions.

leads to an increase in CO2

society to benefit future generations.

**2.1. Outline of the town of Shinchi**

thus, air conditioning is typically required on summer days.

for the town in 2011, which has been declining ever since.

**2. Case community**

results in reduced CO2

emissions per capita. By making cities compact, travel becomes

http://dx.doi.org/10.5772/intechopen.75129

emission

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,

emission. As such, during the reconstruction process following the

Introduction of Low-Carbon Community Energy Systems by Combining Information Networks…

more efficient, and the air conditioning load of housing complexes is reduced, thus increasing energy efficiency [17]. The decrease in energy consumption related to cooling and heating

earthquake, many disaster-affected municipalities aimed to build compact, energy-efficient

This paper examines the advanced case of Shinchi, which is a town located on the northern edge of the Fukushima Prefecture. In Shinchi, after major damage from the Great East Japan Earthquake, a community heat supply system was introduced to link an information and communication technology (ICT) system with a cogeneration system (CGS). The National Institute for Environmental Studies provides academic support for the design and planning

reductions [20, 21]. As a social demonstration experiment, we introduced smart meters and tablet-type display terminals to sample households. Coupled with smart meters, the household display terminals show a variety of information such as real-time energy consumption, comparison with the previous day or year, and electricity-saving messages. Thus, Shinchi is not simply a case of disaster reconstruction but also successful realization of a low-carbon

Shinchi is a small municipality with a population of about 8000 and a total area of 46.53 km2

located about 300 km north of Tokyo, near the border between the Miyagi and Fukushima Prefectures, in the northernmost part of the Fukushima Prefecture on the Pacific Ocean side of Japan (**Figure 1**). The population peaked in 1995 and has since declined, with an aging population and a diminished birthrate. The temperature of Shinchi is low compared to Tokyo, with especially cold winters (**Figure 2**). However, the summer temperatures tend to be high;

In Shinchi, approximately 120 people died as a result of the Great East Japan Earthquake and subsequent tsunami that occurred on March 11, 2011. The tsunami inundated a large area of land 10 m above sea level, with flooding encompassing about 20% of the town. The tsunami destroyed 516 houses; including damage from the earthquake, 630 houses were totally or partially destroyed. The JR Joban Line Shinchi Station was destroyed, and 40% of agricultural land, 420 ha, was inundated. Furthermore, radioactive contamination due to the Fukushima Daiichi Nuclear Power Plant accident resulted in a mean air radiation dose of 0.2–0.6 μSv/h

Before the earthquake, the main railway was the JR Joban Line, but it was closed immediately after the tsunami disaster. The JR Joban Line was reopened in December 2016, allowing access to Sendai, located north of Shinchi. Redevelopment of the district around the JR

Shinchi Station, which was damaged by the tsunami, is currently being carried out.

of such systems, as well as assessing the feasibility, energy conservation, and CO2

cities, with improved energy supply and demand balance [18, 19].

As shown by recent examples, such as locally implemented plans to counteract global warming, formulation of new regional energy conservation visions, and proposals for environmental model/future cities, there are many opportunities for local governments to employ energy-efficient measures and CO<sup>2</sup> emission reduction plans [6]. Energy consumption for cooling and heating is strongly influenced by local factors such as climate, land use, and building-related aspects [7, 8]. The potential for energy and CO<sup>2</sup> reductions from both nonstructural and structural measures is high [9], and there are proposals for such measures that incorporate various regional efforts.

In Japan, energy usage has changed greatly since the 2011 Great East Japan Earthquake [10–12]. Before the earthquake, during the period between the United Nations Framework Convention on Climate Change and the first commitment period prescribed by the Kyoto Protocol, reduction of CO2 emissions was an important policy issue for mid-term to longterm global warming countermeasures. Since the earthquake, there have been many global warming countermeasures and energy policies such as government-imposed power-saving measures to mitigate power peak loading, various programs associated with nuclear power generation, a renewable energy feed-in tariff, and liberalization of power retailers.

There are three reasons that the Great East Japan Earthquake caused changes to energy-related matters. First, the vulnerability of Japan's large-scale energy supply network was exposed. The supply network for power and gas was disrupted during the earthquake, and the energy supply was discontinued over wide areas, even in areas that suffered only minor earthquake damage. In some cases, people survived the earthquake and tsunami but ultimately died due to the absence of power, which resulted in a lack of heating and a shortage of dry clothes. This situation led to a focus on renewable energy as an emergency power source during disasters. Through the introduction of a distributed power supply and construction of an autonomous energy network, energy supply and demand are becoming more efficient at the local scale [13].

Second, the earthquake-related accident at the Fukushima Daiichi Nuclear Power Plant increased the public's awareness of energy supply issues [14–16]. To mitigate peak power loading as the nuclear power plant ceased to function, rolling blackouts and legally binding power usage restrictions were implemented. Additionally, radioactive contamination led to a large-scale evacuation order for residents. During post-disaster reconstruction, many citizens cooperated with energy-saving measures during periods of peak energy demand in summer. As a result, a large number of citizens became aware of energy supply issues.

Third, the Great East Japan Earthquake intensified the problems of depopulation, declining birthrate and the aging population in Japan. For municipalities in disaster-affected areas, these issues are pressing. Population decline along with decentralization of residential areas leads to an increase in CO2 emissions per capita. By making cities compact, travel becomes more efficient, and the air conditioning load of housing complexes is reduced, thus increasing energy efficiency [17]. The decrease in energy consumption related to cooling and heating results in reduced CO2 emission. As such, during the reconstruction process following the earthquake, many disaster-affected municipalities aimed to build compact, energy-efficient cities, with improved energy supply and demand balance [18, 19].

This paper examines the advanced case of Shinchi, which is a town located on the northern edge of the Fukushima Prefecture. In Shinchi, after major damage from the Great East Japan Earthquake, a community heat supply system was introduced to link an information and communication technology (ICT) system with a cogeneration system (CGS). The National Institute for Environmental Studies provides academic support for the design and planning of such systems, as well as assessing the feasibility, energy conservation, and CO2 emission reductions [20, 21]. As a social demonstration experiment, we introduced smart meters and tablet-type display terminals to sample households. Coupled with smart meters, the household display terminals show a variety of information such as real-time energy consumption, comparison with the previous day or year, and electricity-saving messages. Thus, Shinchi is not simply a case of disaster reconstruction but also successful realization of a low-carbon society to benefit future generations.
