建立适应建筑节能的暖通空调设计机制

列举了我国设计机制不适应建筑节能需求的现象。提出了在规划设计中应用综合资源规划(IRP)方法、建立各专业参与的会商制度、将建筑模拟技术用于设计阶段的能耗权衡、建立全程优化调整机制,以及采用基于性能的设计合同等方法,以进一步提高我国暖通空调节能设计水平。     

暖通空调系统几项重点节能设计措施探讨

详细探讨了暖通空调系统的几项重点节能设计措施,主要包括:室内设计计算温度取值、冷热负荷计算、供暖系统设计、风系统设计、空调水系统设计、冷热源选择、补水定压、保温及水力平衡、室温调控与冷热量计量,以供专业人员在工程设计中参考。     

Application of an integrated indoor climate,HVAC and showcase model for the indoor climate performance of a museum

This paper presents a case study on the performance based design of a HVAC system and controller of a museum. A famous museum in The Netherlands has reported possible damage to important preserved wallpaper fragments. The paper provides an evaluation of the current indoor climate by measurements, showing that the indoor climate performance does not satisfy the requirements for the preservation of old paper. To solve this problem we developed an integrated heat air and moisture (HAM) model consisting of models for respectively: the indoor climate, the HVAC system and controller and a showcase. The presented models are validated by a comparison of simulation and measurement results. The integrated model is used for the evaluation of a new HVAC controller design and the use of a showcase. It is concluded that it is not possible to satisfy the indoor climate within the recommended limits, exclusively by the use of a new control strategy. Furthermore in order to meet the recommendations, the wallpaper fragments should be placed in a showcase and a similar control strategy as presented in the paper, has to be implemented in order to limit the room air temperature change.     

城市节能的关键性能指标

根据中国城市能耗特点,提出将城市能耗分为生产性能耗和消费性能耗两大类型。指出生产性能耗主要用效率指标来评价;消费性能耗应尽量用实物量指标来评价,也就是用量化的强度性指标EUI(energy use intensity)评价,实现评价指标的可测量、可核查、可报告。即使采用相对性指标(如百分比指标),也一定要有明确的基准线。提出了城市生产性能耗、消费性能耗以及城市能源系统的关键性能指标。     

对建筑空调系统设计能效比的初步计算分析

以6个实际工程空调系统为例,对全空气系统、风机盘管加新风系统、多联机系统设计工况下的能效比进行了分析计算。结果表明,风机盘管加新风系统的能效比较高,建议在实际工程设计中应重视系统能效比的计算。     

集中供暖和供热中的节能改造问题

通过对工程实例的热损失分析，说明建筑节能改造的关键在于外网改造，主要措施是适当增加保温层厚度，建议对现行有关保温设计规范、标准作必要的修订。     

区域供冷系统的两类能源效率研究

推导出了区域供冷系统分别用于设计前静态计算和运行后系统核算的两类能源效率计算公式,分析了其主要影响因素,可供区域供冷系统设计分析时参考。     

Influence of building parameters and HVAC systems coupling on building energy performance

The performance of different HVAC systems varies when coupled with different buildings. This paper examines the relationship between building heating and cooling load and subsequent energy consumption with different HVAC systems. Two common HVAC systems in use throughout the UK office building stock, variable air volume (VAV) system and fan coil (FC) with dedicated outside air system, have been coupled with a typical narrow plan office building with and without daylight control and for both cellular and open plan.The results presented in this paper clearly indicate that it is not possible to form a reliable judgment about building energy performance based only on building heating and cooling loads. For the two investigated systems, variable air volume system and fan coil with dedicated outside air system, the difference between system demand and building demand varied from over −40% to almost +30% for cooling and between −20% and +15% for heating. If a heat recovery unit is used, the difference in heating performance is even greater, rising to −70%.     

Predicting thermal and energy performance of mixed-mode ventilation using an integrated simulation approach

Mixed-mode ventilation can effectively reduce energy consumption in buildings, as well as improve thermal comfort and productivity of occupants. This study predicts thermal and energy performance of mixed-mode ventilation by integrating computational fluid dynamics (CFD) with energy simulation. In the simulation of change-over mixed-mode ventilation, it is critical to determine whether outdoor conditions are suitable for natural ventilation at each time step. This study uses CFD simulations to search for the outdoor temperature thresholds when natural ventilation alone is adequate for thermal comfort. The temperature thresholds for wind-driven natural ventilation are identified by a heat balance model, in which air change rate (ACH) is explicitly computed by CFD considering the influence of the surrounding buildings. In buoyancy-driven natural ventilation, the outdoor temperature thresholds are obtained directly from CFD-based parametric analysis. The integrated approach takes advantage of both the CFD algorithm and energy simulation while maintaining low levels of complexity, enabling building designers to utilize this method for early-stage decisionmaking. This paper first describes the workflow of the proposed integrated approach, followed by two case studies, which are presented using a three-floor office building in an urban context. The results are compared with those using an energy simulation program with built-in multizone modules for natural ventilation. Additionally, adaptive thermal comfort models are applied in these case studies, which shows the possibility of further reducing the electricity used for cooling.     

谈供热系统节能增效的措施

根据管道水流理论知识,并结合工程实践经验,从一次网热源节能、采用变频系统、改变二次网流量、住户分户计量等方面,分析研究了供热系统节能增效的措施,从而提高冬季供热管网换热站的供热效率,起到节能减排的作用。     

A study of energy performance and efficiency improvement procedures of Government Offices in Hong Kong Special Administrative Region

A study of energy performance in 19 Government Offices in Hong Kong has been carried out. The characteristics of Government Offices, difficulties and results in assessing their building energy performance are discussed and reported. An average Energy Use Index based on unit floor area has been derived for the Government Offices using energy consumption data in the past three years. A number of factors that are likely affect the energy use in buildings, such as year of construction and total gross floor area are reviewed. Energy management opportunities are identified and proposed after carrying out energy audit to the Government Offices. Operational practices to improve energy performance are also recommended.     

Simplified energy prediction method accounting for part-load performance of chiller

This paper presents a simplified correlation method accounting for part-load performance of a chiller. First of all, parametric analysis was to present the influence of each input variable on partial loads at specific time and chiller capacity. Five variables, which were found to correlate well, were selected as inputs on the regression equations. A case study was carried out to test the applicability of this method with a 20 story office building in Seoul. The results of this method show good agreement with DOE-2 and measured data. When three alternatives were assumed for a cooling plant system, the differences of life cycle costs calculated for DOE-2 and this method were within 2%. Accordingly, it is believed that this simplified correlation method can be useful for determining the most economic alternative in the initial design stage.     

Analysis on energy saving potential of integrated supermarket HVAC and refrigeration systems using multiple subcoolers

The paper presents a model-based analysis on the energy saving potential of supermarket HVAC (heating, ventilating, and air-conditioning) and refrigeration systems using multiple subcoolers among the high-temperature HVAC system, the medium-temperature refrigeration system, and the low-temperature refrigeration system. The principle of energy reduction is to have the higher COP (coefficient of performance) system generate more cooling capacity to increase the cooling capacity or reduce the power consumption of the lower COP system. The subcooler could be placed between the medium-temperature and low-temperature systems, between the high-temperature and medium-temperature systems, and between the high-temperature and low-temperature systems. All integration scenarios of adding one, two and three subcoolers have been investigated. The energy saving potential varies with the load ratio between high-, medium- and low-temperature systems, COP of three systems, and the “on-off” duty time of HVAC system. The optimal sequence of adding subcoolers is also proposed.     

A study on the energy performance of a cooling plant system: Air-conditioning in a semiconductor factory

This paper will focus on the energy performance evaluation of a cooling plant system in a semiconductor factory. Several energy saving technologies namely: integrated cooling towers, free cooling systems, control of the chilled water quantity, etc., have been adopted to improve efficiency of the cooling plant system. We have collected actual operating data for 2 years and evaluated the performance of chillers’ COP and the whole cooling plant system's COP and they showed satisfactory results even if the thermal load of the factory was about half compared with design phase assumption.

We also have verified each effect of the energy saving technologies through model-based simulation analysis. The annual electric power consumption dropped about 35% compared to conventional cooling plant systems in case of design phase thermal load. And the faulty status operation of the chiller's number control miss occurred while we monitored. Electric power consumption increased about 17% compared to normal status operation at the same period.     

节能量保证型合同能源管理在建筑节能中的应用

阐述了节能量保证型合同能源管理的实施流程、财务模式,给出了常用的节能解决方案,并针对节能解决方案介绍了节能量的测量与验证方法及节能量的修正方法,对节能量保证型合同能源管理的节能收益进行了分析。     

既有办公建筑大堂地板辐射供冷供暖系统节能改造方案可行性研究

以北京市某既有办公建筑的大堂为研究对象,针对北京地区的气候条件和大堂建筑的空调负荷特性,基于地板辐射供冷供暖技术的基本理论和原理,对该大堂原有的空调方式进行了节能改造,将原来的地板辐射供暖系统改为地板辐射供冷供暖系统。2009年夏季供冷工况运行结果表明,该改造方案不但可满足建筑热舒适性及使用功能要求,而且节能效果显著。     

我国城市污水处理厂节能降耗技术成果

城市污水厂节能降耗项目所取得的各种节能降耗技术,是针对我国城镇污水处理厂目前面临的技术改造和节能降耗问题而展开的,各种成果适合当前和今后很长一段时间的实际需要,特别是直接指导和影响了太湖流域城镇污水处理厂的升级改造,取得明显成效,具有很好的市场潜力和应用前景。部分研发产品填补了我国城镇污水处理产品的空白。同时,通过市场调研和技术研究所提出的各种措施,为今后我国城镇污水处理有关技术政策的制定提供了理论依据。     

空调系统节能改造技术措施分析

本文探讨了空调系统节能改造中具有较好投资回报期的措施,包括风机盘管改造与控制、过渡季节空调箱利用新风供冷、空调系统区域控制、冷冻水变水量控制以及制冷主机改造。     

光伏光热建筑一体化对建筑节能影响的理论研究

对光伏光热建筑一体化(BIPV／T)的两种主要模式建立了理论模型,采用香港地区典型年的气象数据对两种BIPV／T模式的热性能进行了计算分析。与常规建筑相比,光伏光热建筑减少了墙体得热,改善了室内空调负荷状况,提高了建筑节能效果。