Yoshiyuki Shimoda

Evaluation of the thermal environment in an outdoor pedestrian space

To get information for the design of thermal environment in urban outdoor space, field measurements of the physico-thermal environment and a survey of subjective evaluation of the thermal environment by pedestrians were performed. From the results of the survey, it becomes clear that thermal sensitivity of the subjects was affected by the history of exposure and uncomfortable thermal sensation tends to concentrate around intersections.

District-scale simulation for multi-purpose evaluation of urban energy systems

This article presents a simulation model for application to several commercial sector buildings in a particular area to analyse the impact of changes in buildings and building energy systems on the issue domains of mitigation of global warming and heat island phenomena as well as the planning of urban infrastructures for electricity and water. The impact on these issue domains is evaluated using five indicators: primary energy consumption, carbon dioxide emission, sensible anthropogenic heat release, peak electricity demand and water consumption by cooling towers. This article explains the modelling methodology, the simulation model including databases and a case study carried out to demonstrate the simulation capacity of the model. The case study shows that the form and function of buildings influence energy consumption and the five indicators significantly. The trade-off relationship is also shown between the five indicators with respect to changes in the heat-source system of buildings.

Energy Consumption, Efficiency, Conservation, and Greenhouse GasMitigation in Japan's Building Sector

Energy Consumption, Efficiency, Conservation, and Greenhouse Gas Mitigation in Japans Building Sector Authors: Shuzo Murakami (Keio University) Mark D. Levine (Lawrence Berkeley National Laboratory) Hiroshi Yoshino (Tohoku University) Takashi Inoue (Tokyo University of Science) Toshiharu Ikaga (Keio University) Yoshiyuki Shimoda (Osaka University) Shuichi Miura (Tohoku University of A r t & Design) Tomoki Sera (Ministry of Land, Infrastructure and Transport) Masahiro Nishio (Ministry of Economy,Trade and Industry) Yasuhiro Sakamoto (Tokyo Electric Power Company) Wataru Fujisaki (Tokyo Gas) June, 2006 (revised December, 2006) Lawrence Berkeley National Laboratory in collaboration with Japanese institutions identified above

Field Study and Modeling of Semi-Transparent PV in Power, Thermal and Optical Aspects

abstract In this research, semi-transparent PV is proposed as building integrated PV roof for residential application. To understand its characteristics, field measurement was carried out to examine the power generation, thermal and visible light transmission performance of poly-crystalline silicon single glass, poly-crystalline silicon double glass and amorphous silicon single glass semi-transparent PV panels in prototype scale. To confirm parameters needed in accessing semi-transparent PV panels which are seldom provided by manufacturers, calculation models were constructed and verified with field measurement data. This paper reports the findings of experimental and modeling work, which will be fundamental for evaluating semi-transparent PV in overall building energy performance in a later stage of the research. In this study, power generation temperature coefficients are obtained for each panel. For thermal characteristics, various material properties of panels are confirmed. The overall heat transfer coefficients are 4.587 W/m2K, 2.007 W/m2K and 4.379 W/m2K for p-Si single glass, p-Si double glass and a-Si single glass panel respectively. With respect to visible light transmission, semi-transparent PV possesses similar light transmission characteristics with glazing material, and thus could be modeled in the same way as normal glazing material.

A stochastic model to predict occupants’ activities at home for community-/urban-scale energy demand modelling

This paper proposes a stochastic discrete-event model to predict occupants’ activities at home to be used in community-/urban-scale energy demand modelling. The model is designed to consider interactions among household members and generate consistent behaviour across simulated days and times of day with specific time-dependent characteristics. Routine behaviours undertaken routinely everyday such as working and eating meals are placed on the timeline while considering interactions among household members. Gaps between routine behaviours are then filled by non-routine behaviours. Individual specificity and consistency are enhanced by (1) providing input data representing intrapersonal variation instead of interpersonal variation, (2) using relative time to time of routine behaviours, instead of clock time and (3) adjusting the input dataset affecting the selection of non-routine behaviours and their duration. Case studies demonstrated that interactions among household members are reproduced as observed in empirical data and the individual specificity and consistency are enhanced.

Human thermal comfort estimation in indoor space by crowd sensing

Air conditioning in recent BEMS is now being highly automated, but providing true thermal comfort to building occupants and visitors is still challenging due to difficulty of sensing whole 3D space with limited number of sensors. In particular, thermal effect by crowd of people has not been considered so far in such automated air conditioning. This paper presents a method to accurately estimate the thermal comfort of building occupants considering the thermal effect by human crowd. We modify the PMV index, an well-known thermal comfort index, to reflect such effect. This model is further modified to reduce the model parameters, focusing on the behavior and environmental characteristics. Computational fluid dynamics (CFD) simulations have been employed to build the new PMV model. The model was examined in a real field experiment.

Mapping research activities and technologies for sustainability and environmental studies—a case study at university level

Systemic understanding of potential research activities and available technology seeds at university level is an essential condition to promote interdisciplinary and vision-driven collaboration in an attempt to cope with complex sustainability and environmental problems. Nonetheless, any such practices have been hardly conducted at universities due mainly to a lack of appropriate institutional schemes and methodologies to systemically collect, map out, and synthesize individual research activities within a university. In this paper, we present the recent initiative of such systemic and comprehensive understanding of research activities at university level. We carry out a case study, attempting to summarize all the relevant research activities and technology seeds associated with environmental issues and sustainability currently being studied individually at the laboratory level at Osaka University. We collected 138 potential seeds from the universitys relevant schools and institutes and sorted them according to Japans three sustainability visions. The case study demonstrates the universitys potential to provide collective knowledge enabling the societal transition to sustainability if these seeds are systematically overviewed and effectively mobilized to mesh with specific social demands and purposes. We highlight the need for a framework and practice that allows synthesizing research activities and promising technologies even at university level to further facilitate providing collective knowledge and discuss challenges and research needs for promoting synthesis practices and interdisciplinary research that are essential to deal with sustainability problems.

Meso-Level Research towards Low Carbon Society

To achieve the Low Carbon Society, not only the technological progress but also change of the society is required. It includes land use planning, life style, institutional design, consumer’s behavior, and so on. For example, consumer’s choice of energy efficient technology is not always agreed with economical optimum in household economy. In Japan, preference to photovoltaic is very high and there is large amount of willingness to pay for photovoltaic technology. On the other hand, preference to solar water heater is low and total number of installation has been decreasing. The authors propose several types of “eco-design of low carbon society” in residential and commercial sector. Examples are as follows: 1) Design of energy efficient land use. 2) Industrial and institutional design of building integrated solar energy systems.

Synthesis of Research and Technology Seeds at Osaka University – a Discussion for Advancing Sustainability Research

In this paper we first propose a new concept of “meso level” research which aims to provide the linkages between science and technology seeds (micro) and societal visions (macro) with an aim to achieve sustainable societies and then highlight essential components of the meso level. We argue that synthesizing the seeds of science and technology constitutes a core part of meso level research, which has hardly been practiced at university level. We carry out a case study in an attempt to map out and synthesize all the relevant research and technology seeds associated with environmental issues and sustainability, which are currently studied at laboratory level within Osaka University. We collected 138 potential seeds from all the relevant institutes and departments affiliated with the university and sorted the seeds according to Japan’s three sustainability visions at policy level. We show that universities possess a variety of science and technology seeds and could potentially provide collective knowledge that would help facilitate societal transformation towards sustainability, if these seeds are well synthesized for specific purposes. We discuss that it is of importance for universities to be capable of synthesizing research seeds with the view to contributing to achieving sustainable societies.

Versatile Modeling Platform for Cooperative Energy Management Systems in Smart Cities

With growing attention to sustainability and recognition of the impact of global warming problems, energy supply and consumption have become critically important. This paper presents the construction of a modeling platform accommodating cooperative energy management systems (EMSs), which virtually produces the model of a smart city with a distribution network (DN) by using a wide range of data obtained from the real world. The platform involves models of various EMSs, governing the operation of a power system or controlling consumer-installed devices, and simulating the power flow, electrical losses, and voltage in the DN. In addition, indices measuring the sustainability of the model city, such as CO2 emission, are estimated from scenarios, for example, photovoltaic system installation, electric vehicle penetration, etc. The results can be visually displayed and the platform is highly versatile and applicable to various types of issues associated with smart cities. Two case studies are presented in detail.