Daiwa House Group's Developing new communities

First community in Japan to take advantage of power interchange system among multiple single-family houses
SECUREA Toyota Kakimoto (sales completed)

: Environmental, Safety, Comfort, Communication

Toyota City, Aichi Prefecture

SECUREA Toyota Kakimoto - in the city of Toyota, Aichi Prefecture - has been designed to be the first case in Japan of a residential community that realizes the truly efficient use of energy by utilizing an interchange system for low-voltage electric power among single-family houses, together with energy self-sufficient homes made possible by the employment of various solar power electricity generation and storage systems.

Development area : 6,911.02m²
Total units : 21 Single-family houses, 2 rental housings

* According to Daiwa House Industry

SECUREA Toyota Kakimoto is the sixth new town to be developed under the SMAxECO PROJECT, in which Daiwa House Industry Co., Ltd. aims to inject new value into residential communities all around Japan.

In 2014, Toyota City-which has been designated by the Japanese government as an environmental model city-decided to a develop a smart town utilizing a system that enables reduction of CO₂ emissions both by individual homes and by the community as a whole while also cutting peak electric power demand and shifting peak load to off-peak hours. The central aim is to provide residents with affordable energy that is efficiently used and enables a comfortable home life. The city accepted a proposal by Daiwa House, and we were selected as the contractor.

Daiwa House Industry Co., Ltd. has developed Net-Zero Energy Town.* These are a form of "smart town" that fully leverage advanced technologies in three fields-energy conservation, creation, and storage.

SECUREA Toyota Kakimoto embodies still further advances in these technological fields to realize the efficient utilization of energy. At the same time, the community has been designed to serve as a pioneering example of on-the-spot energy generation for on-the-spot consumption, which is effective in minimizing the adverse impact of fluctuations in electric power rates, as well as the ending of the current renewable energy feed-in tariff system.

* These are communities in which net consumption of energy (primary energy equivalent) is more than offset by primary energy generated by the community as a whole.

Efficient use of energy

Power interchange within the residential block, and energy self-sufficient houses

SECUREA Toyota Kakimoto effectively uses the combination of a power interchange system among single-family houses within the entire residential block, and energy self-sufficient houses.

The system of power interchange within the residential block involves the shared consumption among all houses in the block of the electric power generated by the solar power generation systems installed on the roof of each house and the power stored in the lithium ion batteries also installed at each house. Thus, rather than power being generated and consumed by each house separately, these processes are performed through power-sharing by all houses in the block, which realizes greater effectiveness. Moreover, this system does not require the erection and operation of a large-scale management facility, but is achieved merely through rearrangement of the power cable network, with a simple control system. It would thus be easy to adapt the system to other residential communities.

The energy self-sufficient houses are designed to offer their owners comfort while keeping energy consumption to a minimum by utilizing a variety of energy conservation technologies. Energy expenses are also reduced by making use of the optimum timing for operation of household appliances such as water heaters, so as to shift the principal load to off-peak hours. We are currently conducting tests to determine the ideal generating/storage capacity of the solar power generation systems and storage batteries used in these energy self-sufficient homes, taking into account the balance between cost of equipment installation and cost of power purchased from the public utility.

Retail sales contracts for electric power within the power-interchange residential block are arranged and managed by Daiwa Energy Co., Ltd. The lithium ion storage batteries are supplied by ELIIY Power Co., Ltd.

All houses are fitted with a hybrid system consisting of photovoltaic power generation systemand lithium ion storage batteries. All houses are fitted with a hybrid system consisting of photovoltaic power generation systemand lithium ion storage batteries.

Crime prevention and monitoring measures

Monitoring comings and goings at level of the entire block and of individual houses

Security cameras have been installed at the entrance/exit points of the residential block. The existence of these cameras deters persons with criminal intentions from entering the block. Additionally, in the event of a crime, video images are supplied to the police, assisting their efforts to solve the case as quickly as possible.

Also, each home is fitted with an intercom device that includes an Internet-connected camera. When the intercom button is pushed, an image of that person's face is automatically emailed to one or both of the adults of the house. By this means, if a child coming home from school or elsewhere pushes the button, his or her parents can be notified that the child has arrived home safely. In the event that the owner leaves the house and forgets to turn the key in the front door lock, the door can be locked via an email instruction to the house's HEMS (Home Energy Management System).

Formation and maintenance of a comfortable space

Eliminating power-distribution utility poles for a more attractive landscape

To protect the totally coordinated landscape of the housing development into the future, and to maintain the property's value, we have signed the SECUREA Toyota Kakimoto Landscape Agreement, and have laid down a set of town development guidelines.

Additionally, utility lines have been buried underground so that utility poles and lines do not spoil the landscape of the town and people can enjoy a sweeping view of the sky. Moreover, the undergrounding of utility poles and lines improves safety by eliminating the risk of cable disconnection due to the collapse of utility poles in a disaster such as an earthquake.

Utility lines have been undergrounded to ensure residents have a clear, uninterrupted view of the sky.

Communication between people and the community

All residents cooperate in maintenance and operation of jointly-owned property

The community meeting place and the photovoltaic power generation system installed over the retention basin are jointly owned by all the residents of SECUREA Toyota Kakimoto. The administrative corporation formed by all the residents is in charge of deciding on and overseeing maintenance work when necessary on this property, and other issues concerning its operation.

Decisions made by the community's administrative corporation on important issues are made by resolution of all residents at general meetings. The board of directors of the administrative corporation, who are charged with responsibility for overseeing the day-to-day management of the community, are elected from among the residents, giving each resident an opportunity to take an active part in the management process. Part of the building that houses the community meeting place is also used for the storage of tools and equipment that may be needed in the event of a natural disaster, fire, or other accident. Regular liaison is also conducted with the local neighborhood association.

In addition, photovoltaic power generation system (collectively owned by the residents) are installed above the retention basin, which is a communal facility. This is part of the Company's joint development efforts with Toyota City.

Administrative work involved in the operation of the community's administrative corporation is carried out by Daiwa LifeNext Co., Ltd.

The community's photovoltaic power generation system is managed and maintained by the residents.

Comments from the Mayor of Toyota City

Toyota City, which is designated as an environmental model city, aims to be a community whose residents can enjoy affordable energy that is efficiently used and enables a comfortable home life. SECUREA Toyota Kakimoto consists of smart houses equipped with photovoltaic power generation systems, HEMS, and storage batteries, which Toyota City is encouraging its residents to use.

These and other features of future communities have been adopted in this project, and it is my hope that the example of this community will encourage all the citizens of Toyota to incorporate these features into their lifestyles and help attract more people to settle in our city.

Daiwa House's voice

The phenomenon of global warming has become very familiar to us in Japan in recent years, due to the frequency of extreme weather events such as heavy rains-causing natural disasters such as floods and landslides-as well as unprecedentedly scorching hot summers. At the 2015 United Nations Climate Change Conference (COP 21), the Paris Agreement was adopted, a global agreement on the reduction of climate change, under which the parties agreed to set a goal of limiting average global warming to below 2 °C compared to the level prior to the Industrial Revolution.

In developing this residential community, we recognized that it was our duty both to enable the residents to address such environmental issues without asking too much of them, and to realize a community where comfort and convenience are taken to still greater heights. Typical examples of our efforts include the power interchange system within the residential block, and the development of energy self-sufficient houses. We encountered a large number of difficulties while attempting to bring this project to reality, but were able to overcome all obstacles thanks to solutions designed and provided by the various member-companies of the Daiwa House Group.

Currently, the power interchange system enables a reduction in the amount of purchase necessary of electric power from an outside utility company, making the residential block largely self-sufficient for its energy needs. Going forward, we hope to enlist the cooperation of the residents of this power interchange model residential block in conducting experiments to enhance still further the efficiency of energy utilization, and to provide the groundwork for additional technological advances.

In the near future, we plan to fully leverage the experience and technological expertise gained from this project in developing other residential communities that offer residents new value.

Developing new communities