scholarly journals Towards DC Energy Efficient Homes

2021 ◽  
Vol 11 (13) ◽  
pp. 6005
Author(s):  
Daniel Villanueva ◽  
Moisés Cordeiro-Costas ◽  
Andrés E. Feijóo-Lorenzo ◽  
Antonio Fernández-Otero ◽  
Edelmiro Miguez-García

The aim of this paper is to shed light on the question regarding whether the integration of an electric battery as a part of a domestic installation may increase its energy efficiency in comparison with a conventional case. When a battery is included in such an installation, two types of electrical conversion must be considered, i.e., AC/DC and DC/AC, and hence the corresponding losses due to these converters must not be forgotten when performing the analysis. The efficiency of the whole system can be increased if one of the mentioned converters is avoided or simply when its dimensioning is reduced. Possible ways to achieve this goal can be: to use electric vehicles as DC suppliers, the use of as many DC home devices as possible, and LED lighting or charging devices based on renewables. With all this in mind, several scenarios are proposed here in order to have a look at all possibilities concerning AC and DC powering. With the aim of checking these scenarios using real data, a case study is analyzed by operating with electricity consumption mean values.

2021 ◽  
Vol 13 (8) ◽  
pp. 4549
Author(s):  
Sara Salamone ◽  
Basilio Lenzo ◽  
Giovanni Lutzemberger ◽  
Francesco Bucchi ◽  
Luca Sani

In electric vehicles with multiple motors, the torque at each wheel can be controlled independently, offering significant opportunities for enhancing vehicle dynamics behaviour and system efficiency. This paper investigates energy efficient torque distribution strategies for improving the operational efficiency of electric vehicles with multiple motors. The proposed strategies are based on the minimisation of power losses, considering the powertrain efficiency characteristics, and are easily implementable in real-time. A longitudinal dynamics vehicle model is developed in Simulink/Simscape environment, including energy models for the electrical machines, the converter, and the energy storage system. The energy efficient torque distribution strategies are compared with simple distribution schemes under different standardised driving cycles. The effect of the different strategies on the powertrain elements, such as the electric machine and the energy storage system, are analysed. Simulation results show that the optimal torque distribution strategies provide a reduction in energy consumption of up to 5.5% for the case-study vehicle compared to simple distribution strategies, also benefiting the battery state of charge.


Author(s):  
Valerio De Martinis ◽  
Ambra Toletti ◽  
Francesco Corman ◽  
Ulrich A. Weidmann ◽  
Andrew Nash

The optimization of rail operation for improving energy efficiency plays an important role for the current and future market of rail freight services and helps rail compete with other transport modes. This paper presents a feedforward simulation-based model that performs speed profile optimization together with minor rescheduling actions. The model’s purpose is to provide railway operators and infrastructure managers with energy-efficient solutions that are tailored especially for freight trains. This work starts from the assumption that freight train characteristics are completely defined only a few hours before actual departure; therefore, small specific feedforward adjustments that do not affect the surrounding operation can still be considered. The model was tested in a numerical example. The example clearly shows how the optimized solutions can be evaluated with reference to energy saved and robustness within the rail traffic. The evaluation is based on real data from the North–South corridor crossing Switzerland from Germany to Italy.


2016 ◽  
Vol 17 (2) ◽  
pp. 188-207 ◽  
Author(s):  
Nandarani Maistry ◽  
Harold Annegarn

Purpose – The purpose of this paper is to outline efforts at the University of Johannesburg, a large metropolitan university in Gauteng province, to examine energy efficiency within the context of the green campus movement, through the analysis of electricity consumption patterns. The study is particularly relevant in light of the cumulative 230 per cent increase in electricity costs between 2008 and 2014 in South Africa that has forced institutions of higher education to seek ways to reduce energy consumption. Design/Methodology/Approach – A quantitative research design was adopted for the analysis of municipal electricity consumption records using a case study approach to identify trends and patterns in consumption. The largest campus of the University of Johannesburg, which is currently one of the largest residential universities in South Africa, was selected as a case study. Average diurnal consumption profiles were plotted according to phases of the academic calendar, distinguished by specific periods of active teaching and research (in-session); study breaks, examinations and administration (out-of-session); and recesses. Average profiles per phase of the academic calendar were constructed from the hourly electricity consumption and power records using ExcelTM pivot tables and charts. Findings – It was found that the academic calendar has profound effects on energy consumption by controlling the level of activity. Diurnal maximum consumption corresponds to core working hours, peaking at an average of 2,500 kWh during “in-session” periods, 2,250 kWh during “out-of-session” periods and 2,100 kWh during recess. A high base load was evident throughout the year (between 1,300 and 1,650 kWh), mainly attributed to heating and cooling. By switching off the 350 kW chiller plant on weekdays, a 9 per cent electricity reduction could be achieved during out-of-session and recess periods. Similarly, during in-session periods, a 6 per cent reduction could be achieved. Practical implications – Key strategies and recommendations are presented to stimulate energy efficiency implementation within the institution. Originality Value – Coding of consumption profiles against the academic calendar has not been previously done in relation to an academic institution. The profiles were used to establish the influence of the academic calendar on electricity consumption, which along with our own observation were used to identify specific consumption reduction opportunities worth pursuing.


2019 ◽  
Vol 12 (8) ◽  
pp. 2201-2213
Author(s):  
Josefin Borg ◽  
Hannes von Knorring

AbstractThis article explores the complexities of establishing knowledge-sharing practices between organizations through a case study of the creation of a database for energy efficiency measures relevant to the shipping sector. As researchers and policy-makers tend to point towards knowledge sharing and collaboration as means towards a more energy-efficient society, there is a need to better understand the knowledge sharing practices in such initiatives. The study is based upon extensive fieldwork where the first author was recruited to a collaborative network on energy efficiency in the shipping sector, to aid in the development of the collaboration while carrying out participatory-observational research in an ethnographic tradition. The study highlights the need to maintain realistic expectations for new knowledge-sharing collaborations, and the necessity to allow such arrangements to develop over time.


2014 ◽  
Vol 548-549 ◽  
pp. 1815-1819 ◽  
Author(s):  
Xiao Chun Qin ◽  
She Gang Shao ◽  
Yi Shen

Green lighting technology has the advantages of energy efficiency, friendly environment, safety and comfort. Based on the introduction of green lighting technology, taken the Mt. Lushan West Sea tourist highway service as the case study, we analyzed light guide illumination, the optimum use of natural light and energy efficient lighting respectively from the aspects of technical characteristics and the specific highway service application. We finally made the economic analysis in the energy savings of green lights in the highway service, and the result showed that through the use of green lighting systems Mt. Lushan West Sea tourist highway service could save electricity and reduce operating costs 134,700 Yuan per year.


Author(s):  
Lakshmi Shankar Iyer ◽  
Goutam Dutta

The case deals with the unforeseen uncertainties faced by Reva, the first electric car of India, while entering the Indian market. The company was able to take up the challenge of making an energy efficient car. As a new product, Reva achieved operational success, developing an electric, low energy car. Its marketing strategies had limited consumer pull and had to be strengthened to gain consumer acceptance. The ecosystem worldwide is looking for support from governments on the concept and the infrastructure of this product category.


2021 ◽  
pp. 143-155
Author(s):  
Erik Wilhelm ◽  
Wilfried Hahn ◽  
Martin Kyburz

AbstractThis paper is written from the perspective of a Swiss OEM which has been active in the small electric vehicle (SEV) market since 1991 and has put over 22,000 SEVs on the road around the world. KYBURZ Switzerland AG identified several important niche markets for SEVs and today sells vehicles to improve the mobility of senior citizens (e.g. KYBURZ Plus), to increase the efficiency of postal and logistics companies (e.g., KYBURZ DXP), and to imbue drivers with passion for electric vehicles (e.g., KYBURZ eRod). Most KYBURZ vehicles are currently homologated in the category L2e, L6e, or L7e. The company has also developed a Fleet Management product which gives its customers detailed insights into the performance of their electric as well as conventionally powered vehicles. Anonymized datasets from this Fleet Management system will be drawn upon in this paper to examine questions regarding their application, i.e., environmental and economic aspects. The unique feature which the authors from KYBURZ bring with this paper is that all their investigations are performed with real data gained from the field experience. The primary focus of this paper is on last-mile mobility services for postal organizations which help to increase efficiency and meet sustainability goals.


2016 ◽  
Vol 2016 ◽  
pp. 1-180
Author(s):  
Katerina Petrushevska

AIM: This research examines the important issue of energy efficient improvements to the existing building stock through building envelope upgrade. To facilitate this, the energy performance characteristics of the existing building stock were identified with a view to establishing an existing building stock type, where building envelope upgrades can contribute to a higher level of energy efficiency improvements. The literature review along with the selected building precedents was used to establish the best current practice for building envelope upgrades.MATERIAL AND METHODS: Established building precedents and identified best practice for building envelope upgrade, a high rise block of flats was identified and used as a case study, with the current and predicted, following building envelope upgrade, energy performance of the building calculated. This has allowed us to identify the possible energy efficiency improvements for this type of building following the building envelope upgrade. RESULTS: In the projected case, the building with energy class - "D" become class "B". In addition, increased quality of the living room in the attic was enabled. It was possible to obtain a decrease of the heating energy from 130.76 kWh/m²a to 37.73 kWh/m²a or to jump in the class "B" of energetic passport.CONCLUSION: This research contributes to the local implementation of the global agenda for sustainable development, design and construction, and it demonstrates the possible way and level of energy efficiency improvements to the least efficient building stock through existing building envelope upgrade.


Author(s):  
Gökhan GENÇ ◽  
Figen BEYHAN

Although historical buildings are ecological with their construction systems and materials, they cannot provide necessary performance in today's comfort conditions and therefore they are abandoned and remain in a damaged or dysfunctional state. Energy efficient improvement works are carried out in historical buildings in order to bring the historical buildings today's conditions, re-use and ensure their sustainability. However, there are many limitations in these studies due to the heritage characteristics of historical buildings. With these limitations, the works to be done should be carried out with the least intervention without damaging the heritage values of the historical buildings. For this reason, it is necessary to specially select the applications to be realized within the scope of energy efficiency in historical buildings and scaling the physical effects of the applications relative to each other. In this context, in this study, it is aimed to reveal the appropriate improvement methods in order to reach the maximum energy efficiency with the least physical intervention, with the techniques suitable for the historical texture by preserving the original qualities in the historical buildings. Based on the Historic England intervention evaluation scale developed in this framework, 5 scenarios, including the current situation and 4 different design scenarios, including interventions from small to large impacts, were created on a sample historical residential building, and the data of each scenario in terms of energy consumption were obtained. Models created within the framework of the scenarios were evaluated with the Design Builder simulation program, and annual heating and cooling loads and the amount of energy consumed per total m² were obtained. Evaluations were made by comparing the energy efficiency of applications at different degrees with the graphics and tables prepared in the light of these data. As a result, suggestions have been developed regarding the interventions to be made to historical buildings according to the intervention effect sizes in the context of energy efficiency with the evaluations made.


2020 ◽  
Vol 13 (2) ◽  
pp. 90-96
Author(s):  
E.V. Nezhnikova ◽  
◽  
M.V Chernyaev ◽  

The article presents the problems of ensuring energy efficiency of housing construction in the Russian Federation. Unfortunately, for a variety of reasons and, despite the existence of federal and regional legislation, today Russia does not pay due attention to this issue, which leads to an unreasonable increase in electricity consumption both during the creation of residential real estate objects and during their operation. 96 Экономические системы. 2020. № 2 Economic Systems. 2020. No. 2 The relevance of the topic is enhanced by significant energy consumption of residential buildings in use: more than 50% of electrical energy consumption falls on these real estate objects. Therefore, it is no coincidence, but a completely logical trend of the 21st century, that the governments of most countries popularized the idea of designing and building energy-efficient residential buildings. It was established that the improvement of domestic legislation in terms of energy efficiency has greatly improved the regulatory framework for the design and construction of energy-efficient residential real estate.


Sign in / Sign up

Export Citation Format

Share Document