既有公共建筑改造节能效果实例分析

以某既有公共建筑节能改造为例,对比改造前后全年耗电量及分项能耗,分析不同节能改造措施对应的节能效果;通过改造后现场温度实测,分析说明围护结构改造后对室内热环境的影响.研究结果为夏热冬冷地区既有公共建筑节能改造方向和节能改造重点提供参考.     

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.     

Peak load characteristics of Sydney office buildings and policy recommendations for peak load reduction

Growth in peak period electricity demand has driven the requirement for a significant expansion of Sydney's electricity network. Energy efficiency and demand management activities in office buildings may be an alternative to electricity network augmentation, with significant economic and environmental benefits. This paper identifies and characterises trends in electricity peak demand in Sydney's office buildings, comparing a range of high and low energy consuming buildings. The paper assesses the potential for energy efficiency and demand management strategies in office buildings to reduce peak loads and hence defer electricity network augmentation. Base building electricity load data was analysed for a sample of 25 Sydney office buildings, along with Sydney electricity substation and temperature data. Peak loads for buildings with best practice energy performance were found to be 26% lower than for buildings with average energy performance, while annual electricity consumption was 57% lower. With these findings, this paper has assessed the effectiveness of current energy efficiency policy for peak demand management and has recommended strengthening energy efficiency policies in order to capture coincidental peak load reductions, as well as new policies specifically targeting peak demand management. It was found that these measures could offer significant potential to defer network investment.     

Measured energy savings from residential retrofits: Updated results from the BECA-B project

This study summarizes measured data on energy savings from conservation retrofits in existing residential buildings. We have compiled building performance data on approximately 115 retrofit projects (almost twice the size of the initial study) that we put into four general categories: utility-sponsored conservation programs, low-income weatherization programs, research studies, and multifamily buildings. The sample size for each project varies widely, ranging from individual buildings to 33 000 homes. Retrofits to the building shell, principally insulation of exterior surfaces, window treatments, and infiltration-reduction measures, are the most popular, although data on various heating system retrofits are now available. The average retrofit investment per unit in multifamily buildings is approximately $695, far lower than the average of $1350 spent in single-family residences. The median annual space heat savings in the four categories range from 15 to 38 GJ. Savings achieved are typically 20%–30% of pre-retrofit space heating energy use although large variations are observed both in energy savings and in costs per unit of energy saved. Even given the wide range in savings, most retrofit projects are cost-effective. Approximately 75%–80% of the retrofit projects have costs of conserved energy below their respective space heating fuel or electricity prices.     

夏热冬冷地区既有公共建筑围护结构节能改造策略研究——以宁波大学建工楼示范项目为例

建筑节能主要通过新建建筑节能和既有建筑节能改造来实现。现今国家对建筑节能的重视和节能规范标准的不断提高,新建建筑节能工作已取得较大进展,而大量既有建筑的高能耗问题却越来越突出。既有建筑中的公共建筑因能耗高,节能改造潜力大,一直是节能改造的重点。以夏热冬冷地区既有公共建筑为研究对象,结合宁波大学建工楼节能改造世行赠款示范项目实体案例,进行围护结构能耗分析,并在此基础上,通过措施优选,提出该地区外围护结构节能改造策略,为夏热冬冷地区同类建筑节能改造提供参考。     

大型商场节能改造案例研究

大型商场具有内区大、内热扰大、能耗密度大、基本常年需供冷等特点,是大型公共建筑节能改造的重点之一。本文以一个实际的大型商场节能改造为典型案例,通过介绍其节能改造过程及技术,为大型公共建筑或类似建筑的节能改造提供借鉴参考。该案例改造前后能耗实测对比,建筑年能耗约降低98万度电,单位建筑面积中央空调系统能耗由121kWh/m2降低到75kWh/m2,中央空调系统节能率达到38%。     

Enhancing the sustainability and energy conservation in heritage buildings: The case of Nottingham Playhouse

Today, there is a growing interest in developing energy efficient buildings since it is estimated that buildings account for about 40% of the total primary energy consumption in the world. In relation to existing buildings, energy efficiency retrofits have become an important opportunity to upgrade the energy performance of commercial, public and residential buildings that may reduce the energy consumption, demand and cost. In this paper we cover the energy efficiency deep retrofit process that has been carried out for Nottingham Playhouse theatre building for the aim of enhancing its environmental performance and analysing the energy efficiency gained after implementing certain proposed modifications. It is a nationally protected historic building, listed as Grade II1 on The National Heritage List for England (NHLE). The building has had insulation enhancement, doors modifications, solar energy installations, energy-saving lights, in addition to improved heating and air conditioning system. The paper presents a novel methodology; and its results indicate significant improvements in the building's energy performance which is demonstrated using infrared thermographic images and data logger sensors where significant energy savings to the building's thermal performance are obtained. The energy saving measures have been completed while maintaining the heritage building's general appearance and architectural features, which have received a Commendation Certificate from The Nottingham Civic Society for this achievement.     

Green roofs; building energy savings and the potential for retrofit

Green roofs are a passive cooling technique that stop incoming solar radiation from reaching the building structure below. Many studies have been conducted over the past 10 years to consider the potential building energy benefits of green roofs and shown that they can offer benefits in winter heating reduction as well as summer cooling.This paper reviews the current literature and highlights the situations in which the greatest building energy savings can be made. Older buildings with poor existing insulation are deemed to benefit most from a green roof as current building regulations require such high levels of insulation that green roofs are seen to hardly affect annual building energy consumption.As over half of the existing UK building stock was built before any roof insulation was required, it is older buildings that will benefit most from green roofs. The case for retrofitting existing buildings is therefore reviewed and it is found there is strong potential for green roof retrofit in the UK.     

公共建筑能耗统计方法的研究

为全面了解我国公共建筑能耗的基本状况,为建筑节能工作及能源领域的管理决策提供有力的数据支持,有必要在全国范围内建立起科学的公共建筑能耗统计制度。对公共建筑能耗统计体系的建立进行了研究。从公共建筑基本信息、能耗设备的拥有和使用情况及公共建筑日、月、年能耗3个方面建立起公共建筑能耗统计指标体系。设计了公共建筑能耗统计报表。     

建筑运行能耗监测与节能诊断系统的开发

国家机关办公建筑和大型公共建筑的高耗能问题日益突出,该类建筑的节能改革正成为当前建筑节能工作的重点,因此做好此类建筑运行能耗尤其是暖通空调设备运行能耗的监测与节能诊断分析对实现"十一五"节能目标有重要意义.本文设计开发了建筑运行能耗监测与节能诊断系统硬件子系统,该系统不仅能监测耗能量,还能监测用能品质.主要研究内容包括以MS SQL Server 2000作为平台设计了能耗监测与数据信息数据库系统,开发了建筑运行能耗监测数据采集服务器程序与客户端查询分析程序,建筑用户凭密码可在网上查询最新的监测数据并得到分析报告,从而帮助建筑用户实现能源系统由粗放型管理转变为精细型、科学化管理.在此系统基础上,通过工程案例分析,发现空调系统中存在严重的"大流量、小温差"现象和电力系统中存在"三相不平衡"能源浪费问题.     

严寒地区既有居住建筑节能改造方案对比分析

分析了乌鲁木齐市既有居住建筑能耗现状,选取1栋典型建筑,并对其进行改造前的能耗计算。在此基础上确定3种改造方案。对改造方案能耗效益、环境效益及投资成本进行了对比评价,为严寒地区既有居住建筑节能改造提供了参考依据。     

Retrofit cost-effectiveness: Estonian apartment buildings

The economic viability and investment cost of the energy retrofit of apartment buildings are analysed through different energy efficiency levels. To analyse retrofit policy cost-optimal energy efficiency levels and investment costs, a baseline of measured actual energy usage of apartment buildings was created and then individual energy-saving measures and retrofit packages were composed. The cost-optimal level over a 20-year period for apartment building retrofit was a low-energy-building energy performance level, with an investment cost of €150–170/m². Retrofit to low energy building level would be economically viable but the investment capability of apartment owner associations is found to be insufficient for the necessary investments to achieve low-energy-building energy performance. Therefore, it is necessary to determine what levels of financial support can encourage retrofit to occur. The analysis of the current retrofit shows that subsides will increase investment by apartment owner associations into energy efficiency improvements. The target group for energy efficiency retrofit subsidies should be apartment buildings that reach low energy building performance level or at least match the energy performance requirement for new buildings.     

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.     

大型公共建筑运行能耗数据库管理系统初步开发及应用

能耗测试是既有建筑节能改造过程的必要途径,为了对测试数据进行科学有效地管理,作者初步开发了大型公共建筑运行能耗数据库管理系统,并将其应用于若干实际建筑中。本文介绍了该数据库管理系统开发过程,并对其应用结果进行了分析,说明该系统切实可行并发现在建筑耗能系统中存在若干运行问题。     

Zero energy buildings and mismatch compensation factors

This paper takes an overall energy system approach to analysing the mismatch problem of zero energy and zero emission buildings (ZEBs). The mismatch arises from hourly differences in energy production and consumption at the building level and results in the need for exchange of electricity via the public grid even though the building has an annual net-exchange of zero. This paper argues that, when looked upon from the viewpoint of the overall electricity supply system, a mismatch can be both negative and positive. Moreover, there are often both an element of levelling out mismatches between individual buildings and an element of economy of scale. For these three reasons mismatches should be dealt with at the aggregated level and not at the individual level of each building. Instead, this paper suggests to compensate the mismatch of a building by increasing (or decreasing) the capacity of the energy production unit. Based on historical data for the electricity supply area in western Denmark, this paper makes a first attempt to quantify mismatch compensation factors. The results indicate that such compensation factors are a little below one for buildings with photovoltaics (PV) and a little above one for buildings with wind turbines.     

Using dynamic simulation to quantify the effect of carbon-saving measures for a UK supermarket

A standard UK supermarket design is used to simulate the energy performance, and subsequent CO₂ emissions, of a modern-day UK supermarket building. Retrofit measures are proposed to reduce these CO₂ emissions by over 50%, mostly due to demand-side measures but also accounting for likely onsite supply-side solutions. The influence of refrigeration and lighting in such buildings is explored and the possible use of heat recovery systems discussed. The air-tightness of supermarket buildings is also highlighted as a potential area for significant energy savings. Finally, the reliance on grid electricity is demonstrated for non-domestic buildings with a high electrical energy use. A combined approach of energy efficiency and low-carbon offsite electrical generation is suggested from the described case study as the most successful strategy to achieve large carbon savings (i.e. >50%) in existing supermarket buildings.     

Establishing target-oriented energy consumption quotas for buildings

The energy assessment of public buildings is currently emerging as an imperative of the Chinese government. However, in setting the overall control targets for entire regions, effective and specific energy consumption quotas (ECQs) for individual buildings are not specified. In this paper, in an effort to meet the energy conservation targets of the 12th Five-Year Plan, new methods for establishing target-oriented and equitable ECQs are proposed and applied in the assessment of a particular group of government office buildings in Beijing. The respective annual ECQs for electricity and gas were established for each building, and a corresponding year-end assessment was conducted. The core concept of the methods could be applied to other types of buildings and this concept could therefore provide important guidance for future policymaking.     

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.     

上海医院建筑节能改造案例分析

医院建筑是公共建筑中能耗最高的建筑类型.在国家节能减排的大环境下,医院建筑的节能研究相对滞后,医疗主管部门急需了解医院建筑的实际能耗水平和节能潜力,并在此基础上制定相应的能耗考核指标.本文介绍了上海市医院建筑节能改造专题研究和实施试点工作中3家三级甲等医院的节能改造案例,通过对这3家医院节能改造效果进行分析,总结了存在的问题和经验,为医院建筑的相关节能改造工作提供参考.     

合肥市某既有办公楼节能改造及能耗模拟

简要介绍了既有建筑现状和改造要点,运用能耗模拟软件DesignBuilder对合肥市某办公楼建筑改造前后的全年建筑能耗进行模拟,分析各项节能措施的节能改造效果。计算和分析结果表明,经过围护结构、照明系统及空调系统综合改造后,建筑全年能耗比既有建筑能耗降低了33．38％,二氧化碳排放量大大减少。