[Special Feature: Rethinking Japan's Living Environment] Yasushi Ikeda: The Vision of Environmental Housing After 2030 as Seen from Co-Evo House

2021/12/06

The origins of the Keio-style Co-Evolutionary House (commonly known as Co-Evo House) date back to the summer of 2013. A model house intended for public exhibition and performance testing was selected for the Ministry of Economy, Trade and Industry's "FY2013 Project to Promote the Introduction of Innovative Energy-Saving Technologies for Houses and Buildings," along with proposals from four other universities. Through the collaboration of multiple faculty members across departments and the support of dozens of related companies, an exhibition model house implementing various advanced technologies was realized. Co-Evo House inherited the concepts and technical possibilities cultivated there. With support from the Ministry of Land, Infrastructure, Transport and Tourism's "Housing and Building-Related Leading Technology Development Grant Program," the "Keio-style Co-Evolutionary Housing Development Experiment" industry-academia joint research consortium was formed to promote comprehensive technical development research toward practical application based on environmental performance data from residential experiments. Consequently, the house was dismantled and relocated to the Keio University Shonan Fujisawa Campus (SFC) grounds.

The experimental environment on campus, which can also be used as a real detached house, came to be utilized as a testbed for various related research concerning the living environment. It was used as an experimental environment for projects such as the ME-BYO House Lab Project, which collaborated with Kanagawa Prefecture's policy to promote the "ME-BYO" (pre-symptomatic) industry aiming for health promotion through daily living environments; the Open Energy Society project, which researches DC power sharing with neighboring buildings; and the Smart Home Medical Project, which verifies the possibilities of online telemedicine. The results of eight years of discussions and experiments surrounding future environmental housing technology across various fields cannot be easily summarized. During this time, social interest in global environmental issues has grown, and social consensus on energy conservation in housing has made significant progress. The impact of the increasingly sophisticated cyber-socialization driven by the distribution of digital data on our lives has also continued unabated. Furthermore, it is now clear that the social upheaval surrounding infectious disease control since 2020 has shifted our awareness of life, including the living environment. I would like to take this opportunity to look back at the challenges addressed by Co-Evo House.

Looking back, I feel that the origin of the name Co-Evo House, "Co-Evolution," posed an important question. The concept at the time was that the house would learn the resident's lifestyle through artificial intelligence and evolve its functions, while the resident's awareness of life would also evolve in a more sustainable direction, prompted by the environment provided by the house. Behind this was the idea that a system that interactively improves monitoring of activity status and control algorithms would be advantageous for solving diverse conditions.

To begin with, measures to reduce energy consumption in housing under average Japanese climatic conditions are more difficult than in other regions. This is because Japan has both hot, humid summers and reasonably cold winters, with relatively large annual environmental changes. Furthermore, if we turn our attention to the value of the environment during intermediate periods such as spring and autumn when rooms are opened, and the frequency of disaster-level weather events, the range of required responses broadens and systems tend to become complex. While it is possible to maintain a constantly comfortable thermal environment for various different conditions if energy is invested, more individualized methods are required for consumption reduction that considers the use of natural energy and the characteristics of residents, making it difficult to solve everything comprehensively with the same architectural form.

An even more difficult problem is responding to the lifestyles and diverse values of residents in housing. As mentioned earlier, at Co-Evo House, students and others who volunteered stayed for short periods to create a simulated usage state so that data close to actual living conditions could be obtained. Experiments were attempted to simultaneously monitor everything from the energy consumption status of individual devices to environmental measurements such as illuminance and carbon dioxide concentration in various parts, and even the location, amount of exercise, and physical data of the residents inside. However, it was very difficult to evaluate those results simply. At one point, hot water energy consumption spiked despite the solar water heater and fuel cells being in operation. This was because the group of three students staying at the time replaced the bathtub water every single time. Additionally, indirect lighting intended to adjust the color temperature of the room for psychological effect met sufficient illuminance for work brightness, but it was difficult to instruct on proper usage, leading to unexpected energy consumption. Furthermore, many visitors came to test-run the equipment, resulting in unusual data.

Faced with these issues, I naturally considered strictly limiting usage conditions and excluding special data to create "desirable" data, but I also wondered if that would be meaningful. If the same resident stayed continuously, things might be leveled out, but the fluctuations in energy consumption due to differences in individual awareness of life and the purpose of use on a given day were unexpectedly large. I felt some resistance to simply concluding that such trends meant living behavior was not energy-efficient. Whether it was wasteful energy consumption or not is a matter for the individual. On the other hand, when we created a visual console that allowed residents to look back at data during their stay along with activity records, and the residents themselves totaled the energy use they felt was ultimately unnecessary, we found it could be reduced to about two-thirds.

The trend of spending an overwhelming amount of time at home due to the COVID-19 pandemic is likely to continue in the future along with the establishment of remote work. From the perspective of making lifestyles more energy-efficient, this is by no means a bad thing, as it is easier to find ways to reduce energy consumption with constant and stable use. However, did anyone predict that such a major change in life awareness would occur so rapidly and on such a large scale across society? And can we assert that similar things will not happen in the future? For better or worse, the value of a house changes dizzyingly due to changes in the awareness of the user.

One thing that sparked discussion from the beginning at Co-Evo House was an internal floor level difference of about 50 centimeters. Falls in the home for the elderly can lead to being bedridden and are generally considered something to be avoided, but we dared to challenge this taboo to propose the prevention of diseases by promoting exercise in daily life. While we could not conduct experiments on this specifically, I wanted to raise the issue that what constitutes a good living environment changes depending on the physical condition of the resident.

In addition to the elderly, the lifestyles of the child-rearing generation and others change according to their life stages. Because Co-Evo House was tested and evaluated by various users, I was made to think about this more than I initially expected, and I realized that the deeper significance of co-evolution lies in the house acquiring the ability to adapt to these social changes and the accompanying changes in individual lifestyles. Of course, floor level differences do not disappear, so not everything in a house can adaptively follow changes. However, I became convinced that the idea of a system that senses changes in residents and continues to readjust equipment control is a step toward ensuring that a house does not lose its value even when faced with unexpected social changes. As a more obvious and concrete example, systems that determine the priority of power use or self-diagnose the health of a building during power outages caused by large-scale disasters are also addressing the adaptability of housing according to social situations.

Thinking this way, another adaptation challenge emerges: the fact that houses have individual site conditions. Co-Evo House was designed from the start to be dismantled and relocated, and it has actually experienced two locations. Since it is a model house proposal, it was thought that various regions and locations should be assumed.

In general architectural design, it is standard practice to use various surrounding environments of the site—such as the positions of roads and neighboring houses, topography, and trees—as clues. These can be considered more stable and fixed than the lifestyle aspects discussed so far, and viewing site characteristics as effective resources is legitimate in terms of environmental symbiosis. However, as a housing technology development project, we are seeking and proposing general methods that are useful to as many people as possible, so it contains a contradiction from the starting point. If Co-Evo House were to be deployed not just as this one house but as a general method useful over a wide area, the question arises: to what extent should we assume things like solar cells carefully facing south being shaded by a neighbor's house, wind environments created by surrounding topography, or unexpected noise sources making it impossible to open windows? Technologies for inputting these conditions to predict through simulation and search for better solutions have been advancing.

After completion, Co-Evo House was used for research to compare simulations with reality. This became an important hint for thinking about what a house can do to acquire the ability to adapt to different conditions. While simulations cannot predict everything, they are effective for exploring improvement measures from the situation currently faced. Rather, thanks to them, it is possible to make somewhat pragmatic settings as a general solution. And here too, the effectiveness of the concept of co-evolving while using the house was recognized in order to balance the individuality of the solution with the generality of the method for finding it.

Isn't the environmental issue a matter of considering the relationship between an individual's contribution to society and their own happiness? When trying to make the impact on the environment "as small as possible" in housing, one hits a contradiction. This is because the method with the least impact is to do nothing, and ultimately even the necessity of the building itself is questioned. Usually, this is based on a common-sense range that serves as a premise, but if pushed to the limit, it becomes a question of the degree of endurance to avoid future anxiety. On the other hand, the range that humans tolerate after comprehensively comparing various perspectives is wide, and maintaining the current lifestyle is not necessarily the best or sufficient.

It is said that there is no single correct answer in design. This is because the criteria for determining value are not fixed, and both the difficulty and the potential of design lie in this fluctuating value. No matter how small the environmental load, it is meaningless if its lifestyle value cannot be accepted. Conversely, if there are elements that evoke charm, there is great potential. If the very criteria for what is ideal are ambiguous and fluctuating, and if that pulls out the potential of design, then environmental systems as social and personal adaptations exploring that relationship possess sustainability.

Unfortunately, I must admit that data from a single Co-Evo House does not hold much statistical significance. In terms of collecting and analyzing energy consumption data from a large number of houses, house manufacturers and others have begun doing so commercially since Co-Evo House. As a method for reading average trends, it is much more reliable, and such data will increasingly be used on a daily basis. However, as stated in this article, to delve into the relationship between the diversity of individuals—which is the essence of housing—and the environment in a once-in-a-lifetime relationship, it has once again seemed important to build technologies for a co-evolutionary relationship with individual users, which was the starting point of Co-Evo House. In other words, it is important that housing can stay close to and adapt to the changes in the lives of individuals who each walk a different path. At the same time, not only through technologies like predictive automatic control but also through cyber-physical systems that create dynamic equilibrium bi-directionally—such as through visualization that helps humans discover value—digital technology holds the greatest potential to contribute to individuals and society through the difficult challenge of housing.

Perhaps the reason we have been trapped in the idea of applying the results of scientific knowledge as standard general solutions is that we have become too accustomed to the fact that it aligns with mass-production cost-reduction methods and leads to the justice of rationality for society as a whole. This is by no means wrong, but the conflict between responsibility to society and humanism that respects individual humanity appears and disappears as the most familiar and fundamental theme in human living and creation through artifacts. It is fascinating that artificial intelligence, which can be called the ultimate creation humans can conceive, is beginning to get involved there and is casting a stone into that landscape.