Energy Efficient Design Strategies Research Articles

Energy-Aware Scheduling and Resource Allocation for Periodic Traffic Demands

The tremendous growth in high-bandwidth applications and consequent increase in power consumption has underscored the importance of energy efficient design strategies for backbone optical networks. In this paper, we exploit the knowledge of the demand holding times to obtain more power efficient grooming. We consider time-varying, periodic traffic, where the setup and teardown times of the demands may be fixed or vary within a larger time window. The problem of joint scheduling (in time) and traffic grooming, with the goal of minimizing energy consumption for sliding demands, has not been considered previously. We first present an efficient integer linear program formulation for scheduling and allocating resources to a single subwavelength traffic demand, such that incremental energy consumption due to the new demand is minimized. Next, we extend the proposed approach and present a new heuristic that jointly performs scheduling and resource allocation for a large set of periodic demands with the goal of reducing the overall energy consumption of the network for the entire demand set. Through simulations, we demonstrate that significant energy savings can be achieved by considering the demand holding time and show that joint allocation of demands yields additional improvements.

Energy Aware Resource Allocation Based on Demand Bandwidth and Duration

The tremendous growth in high-bandwidth applications and consequent increase in power consumption has underscored the importance of energy efficient design strategies for backbone optical networks. In this paper, we first present an ef–ficient integer linear program (ILP) formulation for allocating resources to a sub-wavelength traffic demand, such that the increase in energy consumption due to the new demand is minimized. The ILP allocates resources to the new de–mand, based on the bandwidth usage and durations of existing demands, as well as that of the new demand. We then extend this approach, and propose a heuristic that performs resource allocation for a set of scheduled, periodic demands with the goal of reducing the overall energy consumption of the network for the entire demand set. We show through simulations that the proposed ILP can quickly generate solutions for practical networks, with hundreds of demands and demonstrate that knowledge of the demand holding times can be exploited to significantly reduce the overall network energy consumption.

The Effect of Façade Design on Lighting Energy Consumption in Offices: A Case Study in Turin, Italy

Energy efficient design strategies should be finalised in the early stages of the building design process. Running costs can be reduced and the occupants' comfort and therefore productivity can increase. Evaluations of different façade systems should be carried out during the design stage in terms of energy demand in order to optimize the project. These evaluations need building simulations predicting the energy consumption. The present work covers a proposed approach to design the façade system and a case study to give an example of application, which is carried out by DAYSIM simulations. Such an approach would enable the design of an optimum façade system providing the visual comfort conditions and reducing electric energy consumption.

Study on energy efficient envelope design for telecommunication base station in Guangzhou

Telecommunication base station (TBS) buildings have large numbers, high energy consumptions and great potentials on energy conservation. Through field investigation of a typical TBS in Guangzhou, the basic information of TBS was achieved, the key factors influencing energy consumption of TBS were determined and several energy efficient envelope designs were proposed. The effect on annual cooling load was analyzed for each energy efficient design and the combined effects were achieved for several combinations of the designs by thermal simulation. The energy efficient design strategy of building envelope for TBS in Guangzhou was proposed.

Energy conservation and building design: the environmental legislation push and pull factors

PurposeThe purpose of this paper is threefold; to investigate the potential impact of energy conservation policies and legislation on building design; examine energy conservation practices in the building industry; and identify associated barriers to an integrated low energy architectural design process.Design/methodology/approachA survey of UK architectural design practices was conducted to assess the impact of current energy conservation policies and legislation on current building design, and ascertain architects' views on the associated barriers and incentives to implementing and sustaining energy conservation strategies in their projects.FindingsResults reveal that building design is affected by existing legislation but often not by policies. Additionally, there is a lack of incentives for the building industry to adopt and implement low energy design strategies that are outlined in existing policies and guidance. Furthermore, results identify a need for increased awareness of the available energy saving technologies.Research limitations/implicationsArchitects are the first point of contact for driving more energy efficient design and conservation strategies. Therefore, this study was confined to a cross section of their opinions of energy conservation within the UK building industry.Practical implicationsThe study is useful for those interested in the current levels of implementation of low energy design strategies and the recommendations for the future of the energy conservation and building design in the UK.Originality/valueThe study of energy conservation and building design provides insights into current environmental design practices; and identifies problems for the implementation of effective and integrated low energy building design process. The content should be of interest to architects, as it highlights the current level of implementation of energy conservation measures in building design.

Energy efficient design strategies in the hot dry area of Turkey

Climate has a major effect on the performance of the building and its energy consumption. This study is based on a student workshop, which has been carried out for a hot dry area of Turkey. The study first aims to show the similarities and the differences of the traditional housing principles from the climate responsive design point of view. Secondly, it aims to put forward the basic principles and their meaningful changes in usage that can be used in the sustainable housing designs of the future. In this study, design strategies in mardin, a town situated in the hot-dry area of the south-eastern part of Turkey, were examined and modern and traditional houses were evaluated in terms of design criteria such as, selection of the area, distance between buildings, orientation, building envelope and building form. In this paper, a simplified thermal evaluation and comparison of a traditional house with a contemporary house have been given by using only data derived from the measurements and this evaluation has been done via both measurements and questionnaires which are carried out for 100 buildings.

Daylighting and energy implications due to shading effects from nearby buildings

Daylighting has long been recognized as a potential energy-efficient design strategy for buildings. Natural light can help reduce the electrical demand and the associated sensible cooling load due to artificial lighting. In Hong Kong, however, many buildings are constructed close to each other and hence the external environment plays a significant role in daylighting designs. This paper investigates the shading effects due to nearby obstructions when daylighting schemes are being employed. We used the computer simulation tool, EnergyPlus, to illustrate the energy performance of a generic commercial building with daylighting controls obstructed by neighbouring buildings of various heights. Analysis of electricity savings was carried out for the perimeter zones of the whole building and individual floors. Regression techniques were conducted to correlate the building energy savings and the angles of obstructions. It was found that the shading effects due to nearby obstructions strongly affect the building energy budget when daylighting designs are used. Building designers should critically consider the external environment in order to achieve energy-efficient building designs.

Climate classification and passive solar design implications in China

Abstract China’s climate differs greatly in various regions, ranging from severe cold to hot and arid to humid. This has significant influences on energy efficient building design strategies and energy use. Solar radiation data from 123 measuring stations were used to propose a map indicating the solar radiation climates in China. A cluster analysis was adopted to identify the prevailing solar climates using the monthly average daily clearness index, K t , as climatic variable. Five major solar climates were identified with annual average K t ranging from 0.3 in the Sichuan Basin to 0.65 in the north and northwest regions. The solar climates were compared with the more widely used general (thermal) climates (severe cold, cold, hot summer and cold winter, mild and hot summer and warm winter) and the major topography (basin, plain and plateau), and implications for building designs were briefly discussed.

Evaluation of energy efficient design strategies for different climatic zones: Comparison of thermal performance of buildings in temperate-humid and hot-dry climate

Since the Kyoto protocol signed in December 1997 the majority of governments around the world have committed themselves to reducing the emission of the greenhouse gases. Thus, efficient use of energy and sustainability has become a key issue for the most energy policies. Sustainability and energy saving terms take place in building construction industry too since buildings are one of the most significant energy consumers. It is known that heating energy demand of a building has a great rate in building total energy consumption. In addition to that, the most of the heating energy has been lost from building envelope. TS 825, Heating Energy Conservation Standard for Buildings in Turkey, aims the reducing of heat loss in buildings through the envelope. But within buildings, one of the fastest growing sources of new energy demand is cooling and especially in hot-humid and hot-dry climatic parts of Turkey cooling season is much longer than the heating season. Moreover in hot-dry climate heat storage capacity of the envelope becomes more important issue than heat insulation for energy efficiency of the building. Since the Turkish standard is considering only heating energy conservation by using degree-day concept, Istanbul and Mardin are considered in the same zone, however those are in temperate-humid and hot-dry climatic zones, respectively. In this study energy efficient design strategies for these climatic zones have been explained and thermal performance of two buildings, which are constructed according to the TS 825 in Mardin and Istanbul cities were evaluated to show the importance of thermal mass in hot-dry climates.

A new simplified thermal design tool for architects

Architects form an integral link in the design of efficient buildings. Energy-efficient design strategies therefore, require architects and engineers to work closely together in optimising the building shell. However, this is not always practical. Architects must therefore, be able to perform a preliminary thermal analysis if energy efficient design strategies are to succeed. Existing tools do not cater for them or fit their design methodology. A need therefore exists for a simplified thermal design tool for architects. This article discusses the development of a tool to fulfil this requirement.

Energy consumption modeling and optimization for SRAM's

The recent trends in portable computing technologies have established the need for energy efficient design strategies. To achieve minimum energy design goals, system designers need a technique to accurately model the energy consumption of their design alternatives without performing a full physical design and full-circuit simulation. This paper presents and compares five approaches for modeling the energy consumption of CMOS circuits. These five modeling approaches have been chosen to represent the various levels of model complexity and accuracy found in the current literature. These modeling approaches are applied to the energy consumption of SRAM's to provide examples of their use and to allow for the comparison of their modeling qualities. It was found that a mixed characterization model-using a CV/sup 2/ prediction for digital subsections and fitted simulation results for the analog subsections-is satisfactory (within /spl plusmn/1 process variation) for predicting the absolute energy consumed per cycle. This same model is also very good (within 2%) for predicting an optimum organization for the internal structures of the SRAM. Several common architectures and circuit designs for SRAM's are analyzed with these models. This analysis shows that global, rather than local improvements, produce the largest energy savings. >