绿色建筑设计中对具有数据中心的两栋办公楼的能量建模分析

EnergyPlus是为上海研发中心的两栋办公楼开发的能量模拟模型,用来评估其采用环保设计之后节能效果,并与基准建筑相对比。作为国际IT公司的研发中心,这两栋楼中具有数据中心,使其不同于一般办公楼。数据中心的IT设备具有高能耗特点,并且需要24h不间断的空调运行。为了达到节能目的,设计时考虑了多种节能措施,如外墙采用高性能材料、轻型建筑系统和HVAC系统。通过能量模型,将提出的设计方式与ASHRAE90·1-2004 compliant budget模型进行对比,以强调与"应用标准"相比之下的节能效果,同时显示了潜在的LEED(tm)Credit EA1节能优化性能。同时,将其与中国规范对比,计算中国公共建筑节能标准中的节能量。整体房屋能量模拟结果显示:这种设计方式下的年均节能,按中国规范能达到大概27%,按ASHRAE建筑预算可节省21%,由于节能优化,可达到LEED信用4级。     

重庆市各类典型公共建筑节能改造效益分析

该文根据重庆市已启动实施的68个国家机关办公建筑与大型公共建筑改造示范项目,对办公、商场、文化教育等三大类建筑节能改造中各单项改造成本、年节约费用进行统计分析,并对这三大类建筑在财政资金补助前后的投资回收期进行对比分析,总结提出了节能改造效益较好的建筑类型,以期有效指导公共建筑节能改造工作。     

A close look at the China Design Standard for Energy Efficiency of Public Buildings

This paper takes a close look at the China national standard GB50189-2005, Design Standard for Energy Efficiency of Public Buildings, which was enforced on July 1, 2005. The paper first reviews the standard, then compares the standard with ASHRAE Standard 90.1-2004 to identify discrepancies in code coverage and stringency, and recommends some energy conservation measures that can be evaluated in the design of public buildings to achieve energy savings beyond the standard. The paper also highlights several important features of 90.1-2004 that may be considered as additions to the GB50189-2005 standard during the next revision. At the end the paper summarizes the latest developments in building energy standards and rating systems in China and the US.     

Whole building energy simulation and energy saving potential analysis of a large public building

This article explores how to use EnergyPlus to construct models to accurately simulate complex building systems as well as the inter-relationships among sub-systems such as heating, ventilation and air conditioning (HVAC), lighting and service hot water systems. The energy consumption and cost of a large public building are simulated and calculated for Leadership in Energy and Environmental Design (LEED) certification using EnergyPlus. American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) baseline model is constructed according to ASHRAE 90.1 standard and the comparison of annual energy consumption between ASHRAE baseline model and proposed model is carried out. Moreover, an energy efficiency (EE) model is built based on the design model. Meanwhile, other energy conservation measures (ECMs) such as daylighting dimming and occupant sensors are considered. The simulation results show 4.7% electricity consumption decrease but 6.9% gas consumption increase of the EE model compared to ASHRAE baseline model. In summary, the annual energy cost of the EE model is reduced by 7.75%.     

办公建筑节能设计思考

本文基于节能建筑设计的基本原理,从办公建筑节能设计的一般原则、建筑的体型控制、自然采光与通风的节能设计、建筑的外围护结构及遮阳设计等方面对办公建筑节能设计实践进行分析,指出现代办公建筑节能设计的重要性,并提出设计技术手法及其应用的可能与前景。     

湿热气候下高层办公楼气候适应性设计——以广东交通设计大厦为例

揭示湿热气候下高层办公楼气候适应性设计策略与应用逻辑,为我国高层办公楼的绿色设计提供借鉴与参考。运用建筑气候适应性思想,聚焦方案设计阶段,通过案例归纳与分析气候特征,总结湿热气候下绿色高层办公楼在隔热、遮阳、通风、节能方面的设计策略。并通过广东交通设计大厦项目实践,在城市、建筑与细部尺度将气候适应性设计策略有效运用,深刻塑造了建筑的形体与空间特色。高层办公楼气候适应性设计,有益于创造出适应气候环境、更加节能健康的绿色建筑。     

Improving energy performance of school buildings while ensuring indoor air quality ventilation

Energy conscious design of school buildings, as well as deemed-to-satisfy provisions in a Performance Based Energy Code, should address the problem known as the energy efficiency—thermal comfort—indoor air quality dilemma (EE-TC-IAQ Dilemma). In warm and moderate climates, the large internal heat sources usually found in school buildings prevent achieving thermal comfort without active cooling in summer, but are not sufficient to eliminate the need for heating in winter. Commonly used air-conditioners do not improve air quality, while natural ventilation induces uncontrolled energy losses. In this study, a step by step process was used for the development of deemed-to-satisfy design solutions, which cope with the EE-TC-IAQ Dilemma, for a performance based code. A distinction is made between improving building design variables and improving ventilation schemes. Results indicate that implementation of improved ventilation schemes in an otherwise well designed energy-conscious building result in savings of 28–30% and 17–18% for northern and southern classroom orientations, respectively.     

Policy options towards an energy efficient residential building stock in the EU-27

The EU-27 residential building stock offers high potential for energy efficiency gains. The policies already in place or proposed to improve the energy efficiency and thus the environmental performance focus on new buildings and major renovations of existing buildings. However, there might be additional measures that could lead to further energy efficiency improvements. In particular, the installation of roofs or windows that show a high thermal efficiency outside major renovations offer a large improvement potential. In this study, the potential environmental and economic impacts of two types of such policy options were analysed: first, measures that require high energy efficiency standards when roofs or windows have to be replaced; and, second, measures that accelerate the replacement of building elements. The results suggest that the two policies offer the potential for substantial additional energy savings. In addition, the installation of energy efficient building elements comes at negative net cost. When the replacement of building elements is accelerated, however, the additional costs do not outweigh the energy cost savings.     

An object-oriented energy benchmark for the evaluation of the office building stock

Energy benchmarking is useful for understanding and enhancing building performance. The aim of this research is to develop an object-oriented energy benchmarking method for the evaluation of energy performance in buildings. Statistical analysis of the four-year monitored energy consumption data for office buildings was conducted. The results show that the energy use intensity follows the lognormal distribution with the Shapiro–Wilk normality test. Based on the lognormal distribution, the energy rating system for office buildings has been established. An object-oriented energy use intensity quota determination model has been developed. This research provides practical tools that enable decision-makers to evaluate a building's energy performance and determine the energy benchmark.     

A cost effective approach to design of energy efficient residential buildings

The objective of this study is to identify cost-optimal efficiency packages at several levels of building energy savings. A two-story residential building located in Jordan is selected as a case study. DesignBuilder software is used to predict the annual energy usage of a two-story residence in Irbid, Jordan. Real-time experimental data from a single isolated controlled room was used to verify the proposed model. In addition to energy analysis, the economic, environmental, and social benefits of the proposed design have been investigated. The sequential search optimization approach is used to estimate the minimum cost of the building while considering various design scenarios. In addition, the impact of various energy conservation techniques on residential buildings is assessed, and the payback period for each program is calculated. Ultimately, the optimal combination of design to achieve energy efficiency measures has been identified in several climate regions. The simulations results predict that the annual electricity consumption can be reduced up to 50% if the proper combinations of energy conservation measures are selected at the lowest cost. The payback period is 9.3 years. Finally, energy efficiency measures can lead to a total of 9470 jobs/year job opportunities.The study provide practical framework to link between energy performance criteria and economic goals of building. Linking the energy performance requirements to economic targets provides guidelines for homeowners, contractors, and policymakers for making a suitable decision regarding the retrofitting of existing residential buildings. The study focuses on developing new methodologies that support minimizing costs during a building's lifecycle while maximizing environmental benefits which can not be identified by a series of parametric analyses using individual energy-efficient measures.     

Life cycle energy assessment of a typical office building in Thailand

A typical office building in Thailand was analyzed using the life cycle energy analysis (LCEA) method to illustrate the argument. Results indicate that although life cycle energy (LCE) distribution is concentrated at the operating phase, the embodied energy of buildings is a non-negligible fraction of the LCE balance. Energy (electricity) used for lighting and HVAC systems in the operation phase and; the manufacture of concrete and steel were the most significant elements in the buildings life cycle. Application of a combination of energy saving measures, showed that 40-50% of energy (electricity) used in a typical office building in Thailand can be saved. Preliminary analysis indicated that recycling building materials can also contribute additional energy savings (about 8.9%) to a buildings LCE profile. Therefore reducing energy consumption should be a priority for not only the operation but also other life cycle phases. It is suggested that both embodied and operating energy should be accounted for within the context of energy efficiency through the incorporation of LCEA into the existing Thai building energy code.     

Predicting building energy requirements

This paper is concerned with methods of predicting the thermal performance and energy consumption of buildings. The advantages and drawbacks in practical office situations of both approximate methods and the more precise computer methods are discussed. The widespread use of the computer for these calculations will be necessary for implementation of a National Energy Conservation Standard for building design. The new ASHRAE Standard 90–75 essentially requires such computer methods.A case study carried out for the State of California in an effort to determine the practicality of energy budgets is discussed.The outputs of four proprietary energy programs for the same two buildings are compared and found to be remarkably different. The need for an ASHRAE-endorsed public domain computer program is discussed.     

Life-cycle carbon and cost analysis of energy efficiency measures in new commercial buildings

Energy efficiency in new building construction has become a key target to lower nation-wide energy use. The goals of this paper are to estimate life-cycle energy savings, carbon emission reduction, and cost-effectiveness of energy efficiency measures in new commercial buildings using an integrated design approach, and estimate the implications from a cost on energy-based carbon emissions. A total of 576 energy simulations are run for 12 prototypical buildings in 16 cities, with 3 building designs for each building-location combination. Simulated energy consumption and building cost databases are used to determine the life-cycle cost-effectiveness and carbon emissions of each design. The results show conventional energy efficiency technologies can be used to decrease energy use in new commercial buildings by 20-30% on average and up to over 40% for some building types and locations. These reductions can often be done at negative life-cycle costs because the improved efficiencies allow the installation of smaller, cheaper HVAC equipment. These improvements not only save money and energy, but reduce a building’s carbon footprint by 16% on average. A cost on carbon emissions from energy use increases the return on energy efficiency investments because energy is more expensive, making some cost-ineffective projects economically feasible.     

Data center design and location: Consequences for electricity use and greenhouse-gas emissions

The rapidly increasing electricity demand for data center operation has motivated efforts to better understand current data center energy use and to identify strategies that reduce the environmental impact of these buildings. This paper builds on previous data center energy modeling efforts by characterizing local climate and mechanical equipment differences among data centers and then evaluating their consequences for building energy use. Cities in the United States with significant data center activity are identified. Representative climate conditions for these cities are applied to data center energy models for several different prototypical space types. Results indicate that widespread, effective economizer use in data centers could reduce energy demand for data centers by about 20–25%, equivalent to an energy efficiency resource in the US of ∼13–17 billion kWh per year. Almost half of the potential savings would result from better airflow management and proper control sequences. The total energy savings potential of economizers, although substantial, is constrained by their limited potential for use in server closets and server rooms, which together are estimated to account for about 30% of all data center energy demand. Incorporating economizer use into the mechanical systems of larger data centers would increase the variation in energy efficiency among geographic regions, indicating that as data center buildings become more energy efficient, their locations will have an increasing effect on overall energy demand. Differences among regions become even more important when accounting for greenhouse-gas emissions. Future data center development could consider site location, along with efficiency measures, to limit the environmental impact attributable to this increasingly prominent economic sector.     

A screening methodology for implementing cost effective energy retrofit measures in Canadian office buildings

Private and public sectors own and operate an array of office buildings that consume energy and contribute to the emission of greenhouse gases (GHG). Energy demands can be reduced by applying energy retrofit measures (ERMs) to existing buildings. The choice of ERMs involves evaluation of applicability, energy end uses and cost of application versus energy savings. This paper describes a methodology developed to screen office buildings for their current level of energy consumption and potential for retrofit application. Selection of an optimal set of ERMs is influenced by climate, occupancy, heating and cooling systems, envelope properties and building geometry. When assessing the implications of applying ERMs to a large building stock it is vital to screen the complete building set for optimal retrofit opportunities. This can be accomplished by characterizing office building stock into a manageable set of archetypes and simulating building operation using energy simulation software. Using regression analyses, a model was developed for estimating the energy consumption. Present value analysis was used to optimize the evaluation of the various ERMs. The methodology developed can be used to simplify the ranking of buildings for retrofit; to select and combine ERMs, and to plan energy and GHG reduction activities.     

Improving energy benchmarking with self-reported data

Energy benchmarking for buildings has become increasingly important in government policy and industry practice for energy efficiency. The questions of how energy benchmarking is currently conducted, and how it might be improved using rapidly growing quantities of self-reported data, are examined. A case study of commercial office buildings in New York City demonstrates how the rapid growth in self-reported data presents both new opportunities and challenges for energy benchmarking for buildings. A critique is presented for the scoring methodology and data sources for Energy Star, one of the largest and most successful benchmarking certification schemes. Findings from recent studies are examined to illustrate how this certification currently works in the marketplace. Self-reported building energy data are rapidly growing in Portfolio Manager (the user interface to Energy Star) due to mandatory energy benchmarking laws, and can be used to improve Energy Star's current scoring methods. These self-reported data are tested and improved for analysis by applying theories and methods of data quality developed in computer science, statistics and data management. These new data constitute a critical building block for the development of energy efficiency policies, and will affect how government, consultants, and owners measure and compare building energy use.     

Opportunities for reversible chillers in office buildings in Europe

Europe with more than 600 millions of square meters of air-conditioned office buildings offers an opportunity to save energy and reduce CO₂ emissions by reconverting chillers into reversible heat pumps in office buildings. One of the questions asked in the framework of the IEA ECBCS Annex 48 is how to assess the energy saving potential and how to identify the most interesting building cases. The methodology proposed here is based on the simulation of office buildings representative of the building stock. The energy consumption has been simulated for different office building types in five European climatic zones on the one hand with boilers for heating and chillers for cooling, and on the other hand with reversible chillers plus back-up boilers. The results of the simulations in terms of energy consumption allow us to assess the primary energy savings and CO₂ emission reduction in Europe by reconverting chillers into reversible heat pumps. The results show that the potential of annual primary energy savings and annual CO₂ emission reduction are about 8 TWh_PE and 3 millions of tons of CO₂ in Europe-15. Even if the temperature level in terminal units can be solved using the cooling coil instead of the heating coil, a back up boiler turns generally out to be required for the coldest days in the year or when simultaneous heating and cooling demands occur.     

Designing energy efficient commercial buildings—A systems framework

This paper provides a means for improving the effectiveness of energy related decision-making during the design phase of a building. A review of the literature and discussions with experts revealed that several approaches for an Integrated Design Process for energy efficient buildings exist. However, most of these approaches are relatively abstract and philosophical in nature, and do not prescribe procedures that enable energy efficient design.This paper attempts to address this gap by proposing a comprehensive design process titled the ‘Integrated Energy-Efficient Building Design Process’ (IEBDP). This process provides a framework based on systems theory that facilitates the integration of various facets of the energy-efficient alternatives selection process. In addition, the proposed framework seeks to integrate state-of-the-art analysis tools and methods, to aid designers in performing holistic building design. Analytical Hierarchy Process (AHP), a multi-attribute decision-making technique is used to resolve conflicts amongst diverging design goals.The proposed IEBDP framework was then used to design an office building, taken as a case study, in the composite climate of New Delhi, India. It was found that considerable energy savings could be achieved by following the IEBDP process. The benefits of this framework vis-a-vis traditional energy efficient design approaches were evaluated by comparing the design done through the IEBDP process with designs submitted by a group of practicing architects. The various designs were evaluated in terms of strategies adopted, the level of exploration as well as design integration, in order to validate the applicability and use of the IEBDP framework.     

夏热冬暖地区绿色建筑性能后评估研究

为了解夏热冬暖地区绿色建筑运行后实际能耗和室内环境品质，文章详细介绍了该气候区内绿色建筑主要技术的应用情况及应用效果。选取位于该气候区内共11个获得绿色建筑认证的办公建筑，通过调研实际能耗，结合用户主观问卷调研，与常规办公建筑的能耗和室内环境品质主观满意度进行了对比研究。结果表明，对于A类办公建筑，绿色建筑与常规建筑无明显差异，均略低于引导值；对于B类而言，绿色办公建筑的总能耗显著低于常规办公建筑，但与能耗指标相比二者能耗均较高，是建筑节能工作的重点。在室内环境品质满意度方面，用户对绿色建筑的满意度明显高于常规建筑，在空气品质和室内环境控制上尤为明显，光环境的差异则更多是归因于天然采光的设计，而非人工照明的优化。最后通过一个案例从节地、节能和室内环境等3个方面全面地介绍了适宜于夏热冬暖地区的绿色建筑设计。     

江西省某办公建筑的行为节能分析

目前我国建筑运行能耗约占我国全社会总能耗的30％,建筑节能降耗是摆在我们面前的重要课题。笔者通过对江西省某办公建筑电能消耗特点的研究分析,找出其用能不合理之处,进而提出节能管理方法,力求无成本或低成本的节能改造,降低建筑的能源消耗。