Experimental Validation of Hydrogen Fuel−Cell and Battery−Based Hybrid Drive without DC−−DC for Light Scooter under Two Typical Driving Cycles

Faced with key obstacles, such as the short driving range, long charging time, and limited volume allowance of battery−−powered electric light scooters in Asian cities, the aim of this study is to present a passive fuel cell/battery hybrid system without DC−−DC to ensure a compact volume and low cost. A novel topology structure of the passive fuel cell/battery power system for the electric light scooter is proposed, and the passive power system runs only on hydrogen. The power performance and efficiency of the passive power system are evaluated by a self−developed test bench before installation into the scooters. The results of this study reveal that the characteristics of stable power output, quick response, and the average efficiency are as high as 88% during the Shanghainese urban driving cycle and 89.5% during the Chinese standard driving cycle. The results present the possibility that this passive fuel cell/battery hybrid powertrain system without DC−DC is practical for commercial scooters.

VALIDATION OF SPECTRAL SIMULATION TOOLS FOR THE PREDICTION OF INDOOR ELECTRIC LIGHT EXPOSURE

As the interest in design applications related to responses to light beyond vision is growing, two simulation tools, ALFA and Lark, have been developed to incorporate spectral characteristics of light in the evaluation of indoor lighting conditions. The spectral characteristics of light are of particular relevance when studying ipRGC-influenced responses. This paper aims to assess the reliability of these tools in predicting indoor spectral irradiance specifically from electric lighting. Spectral irradiance was measured under three indoor electric lighting scenarios and compared against spectral irradiance simulated in ALFA and Lark. While the outcomes of the study tend to show that ALFA is both more accurate and faster, rather large errors were found for spectral irradiance (-28.6% to 33.4%). In comparison to a prior study focusing on daylighting, these results seem to indicate that spectral simulations of electrically lit scenes are generally less accurate than those of daylit scenes with these tools.

INTEGRATION OF DAYLIGHT WITH ELECTRIC LIGHTING IN COMMERCIAL BUILDINGS: A CASE STUDY FROM NEPAL

Daylight attributes to the aggregate of direct and indirect lights originating from the sun during the daytime. Integrating daylight with electrical lighting can serve as a means to lessen electricity costs for buildings. Geographic location and weather conditions facilitate most of the areas of Nepal to receive on average 12 hours of daylight and have huge energy-saving potential. However, the integration of daylight has not been admitted in the building code of Nepal. Moreover, contemporary architectural design lacks employment of techniques illustrated by illumination engineering to integrate daylight. This study analyses the plausibility and benefits of integrating daylight with electric light for a typical commercial building of Nepal employing the DIALux model and simulation. Simulation integrating energy-efficient electric light and daylight was done to observe illumination levels and light power density. For daylight performance, year-round conditions were observed for three different sky types. Modification of building architecture to integrate daylighting components was also studied. In the later part of the study, analysis was done to observe energy-saving potential and financial benefits. Results designated the plausibility of blending daylight with electrical lighting in the building for all-sky conditions. Extensive energy thrift was observed and was higher with added daylight components. Recommendations of the study to blend light sources and incorporation of daylight components are attainable with current technology and trend in Nepal with accompanying benefits of energy-saving, reduced operation, and reduced maintenance cost.

Cultures of light: Electric light in the United States, 1890s-1950s

<p>Cultures of Light is set within a period that stretches from the late nineteenth to the mid-twentieth century in the United States, an era in which nearly every aspect of American life was impacted to a lesser or greater degree by the introduction, distribution and integration of electric power and light. By no means attempting to comprehensively examine the impact and effects of this expansive transformation, this thesis has a narrow but meaningful target, defined by key intersections of electric lighting and American culture. Primarily concerned with the investigation of culturally bound ideas and practices as mediated through electric light and its applications, my thesis is focused on particular instances of this interplay. These include its role in supporting nationalizing narratives and agendas through large-scale demonstrations at world’s fairs and exhibitions, in the search for and expression of modernism and its variations in the United States. Similarly electricity and electric light throughout the better part of the twentieth century was scaled to the level of the individual through a number of mechanisms and narratives. Most prominently the electric light industry employed gendered discourses, practices and beliefs in their efforts to grow the market, calling upon the assistance of a host of cultural influencers, from movie stars to architects to interior designers, instigating a renegotiation of established approaches to the design of architecture and the visual environment. Connecting common themes and persistent concerns across these seemingly disparate subject areas through the examination of cultural beliefs, practices, rituals and traditions, Cultures of Light seeks to illustrate the deep and lasting significance of electric light within American society in the twentieth century.</p>

Cultures of light: Electric light in the United States, 1890s-1950s

<p>Cultures of Light is set within a period that stretches from the late nineteenth to the mid-twentieth century in the United States, an era in which nearly every aspect of American life was impacted to a lesser or greater degree by the introduction, distribution and integration of electric power and light. By no means attempting to comprehensively examine the impact and effects of this expansive transformation, this thesis has a narrow but meaningful target, defined by key intersections of electric lighting and American culture. Primarily concerned with the investigation of culturally bound ideas and practices as mediated through electric light and its applications, my thesis is focused on particular instances of this interplay. These include its role in supporting nationalizing narratives and agendas through large-scale demonstrations at world’s fairs and exhibitions, in the search for and expression of modernism and its variations in the United States. Similarly electricity and electric light throughout the better part of the twentieth century was scaled to the level of the individual through a number of mechanisms and narratives. Most prominently the electric light industry employed gendered discourses, practices and beliefs in their efforts to grow the market, calling upon the assistance of a host of cultural influencers, from movie stars to architects to interior designers, instigating a renegotiation of established approaches to the design of architecture and the visual environment. Connecting common themes and persistent concerns across these seemingly disparate subject areas through the examination of cultural beliefs, practices, rituals and traditions, Cultures of Light seeks to illustrate the deep and lasting significance of electric light within American society in the twentieth century.</p>

Studies on Energy Consumption of Electric Light Commercial Vehicle Powered by In-Wheel Drive Modules

This article presents the results of energy consumption research for an electric light commercial vehicle (eLCV) powered by a centrally located motor (4 × 2 drive system) or motors placed in the vehicle’s wheels (4 × 4 drive system). For the considered constructions of electric drive systems, mathematical models of 4 × 2 and 4 × 4 drive systems were developed in the Modelica simulation environment, based on real data. Additionally, the influence of changes in the vehicle loading condition on the operation of the motor mounted in the wheel and the energy consumption of the drive module was investigated. On the basis of the conducted research, a comparative analysis of energy consumption by electric drive systems in 4 × 2 and 4 × 4 configurations was carried out for selected test cycles. The tests carried out with the Worldwide harmonized Light vehicles Test Cycles (WLTC) test cycle showed a roughly 6% lower energy consumption by the 4 × 4 drive system compared to the 4 × 2 configuration.

Toward a Connected System—Understanding the Contribution of Light from Different Sources on Occupants’ Circadian Rhythms

Light that enters humans’ eyes and impacts circadian rhythms may come from various sources, including the sun, electric lighting systems, and self-luminous displays. Occupants’ activities strongly impact the light entering their eyes, which is difficult to predict and not yet well understood. This study investigated the circadian contributions of light from different sources in real building environments to better understand the variables that influence the circadian health of occupants. Spectral irradiance distributions at a position equivalent to the front of an eye of a seated occupant in various interior office spaces were collected. Daylight and electric light were measured separately, and light emitted from displays was measured when a variety of different computer tasks was performed. Circadian stimulus (CS) and α-opic irradiance, defined by CIE DIS026/E:2018, were further calculated, and the circadian effects of light from different sources were compared. The results show that daylight has the greatest circadian effect, while electric light in spaces that were predominantly designed with conventional downward lighting has a very limited impact. The circadian effect of light from screens was considerably high. The outcomes suggest that, to optimise the circadian effects of light, connected lighting systems are needed to control light from different sources.

Subtask A: User perspective and requirements - A.2 Use cases

The report starts with the introduction, chapter 1, where the main objective of the work is formulated, namely, to examine how the public buildings are used regarding lighting; both daylight and electric light is considered. In the chapter 2 a review of codes and requirements has been done. It starts with a discussion about general aspects of codes (subchapter 2.1) and presentation of international standards CEN and ISO (2.2) and follows with description of CIE reports and other internationally recognized guidance books (2.3). Then national recommendations are also presented (2.4). Finally, the impact of codes on architectural design is elaborated based on the interviews with architectural offices (2.5).

How can electric lighting contribute to human health and well-being?

Electric light in buildings may provide some health benefits; however, for most people these benefits are likely to be small. It is possible for electric lighting to cause health problems, if there is too little light or there is glare, but for the most part there is good guidance available and these problems can be avoided. The quality of the lit environment can have a psychological impact and this may in turn impact well-being. A starting point for this is perceived adequacy of illumination. Related lighting metrics are examined and a hypothetical explanation is suggested.