基于热负荷承载的多热源环状管网节能优化模型

多热源环状管网的热源分布位置、热网结构、热负荷分布及密度等均会影响热网的造价和运行费用。基于热负荷承载方法,构建多热源环状管网的节能优化模型。根据多热源环状管网的相关数据调整优化指令,对多热源环状管网的组成与机制进行分析,以相对热负荷的定义为基础构建节能优化模型。结果显示：优化模型运行9.8 s时,得到最优解集。     

绿色建筑热源及输配管网系统节能性研究

针对吉林省2个绿色建筑示范工程进行现场测试,研究其热源及输配管网系统的节能性,并将测试结果与普通建筑进行对比,通过对比发现:绿色建筑在热源及输配管网环节节能效果与普通建筑相比并无明显优势。就这2个示范工程来说,所谓的绿色建筑在热源及输配管网节能性方面并非一定优于普通建筑,结合吉林省实际情况,提出了绿色建筑在热源及输配管网环节可采用的节能技术,以便有效地提高节能效果。     

地热水水源热泵在校园建筑的应用

探讨了校园建筑冷、热负荷的特点，介绍了适用于校园建筑供暖、供冷的冷热源。结合某工程实例，研究以水源热泵机组作为冷热源的水源热泵系统，并针对校园建筑冷、熟负荷特点，修正了冷热负荷。分析了水源热泵系统的经济性、环保性及校园建筑采用水源热泵作为冷热源的优势。     

热回收型空气源热泵在室内游泳馆的应用

介绍了热回收型空气源热泵机组的工作原理及运行模式.并以上海地区公共娱乐型室内游泳馆为例,分析了此类建筑空调负荷以及池水加热和沐浴用热水负荷分布规律.对将热回收型热泵机组作为其冷热源的可行性进行分析探讨.     

超低能耗建筑中土壤源热泵系统的应用分析

在分析现行节能标准建筑与超低能耗建筑冷热负荷的基础上,对比北京某办公建筑在现行节能标准建筑与超低能耗建筑标准下的负荷差异,相对现阶段节能标准建筑,建筑热负荷大幅减小,冷负荷则变化不大,同时负荷分布更均匀。通过Fluent软件模拟北京地区在设计工况下单孔地埋管换热器运行30 d的运行性能。最后,在超低能耗建筑标准下,采用TRNSYS软件模拟土壤源热泵时机组的相关性能参数。随后通过TRNSYS模拟比较不同钻孔深度与钻孔间距时土壤源热泵系统性能差异。     

兰州地区住宅建筑供暖能耗影响因素分析

为研究影响兰州地区住宅建筑供暖能耗的因素,在围护结构参数完全符合国家现行寒冷地区住宅建筑节能要求的前提下,以兰州市2栋住宅建筑为基准模型,运用De ST-h软件对供暖季的热负荷进行逐时模拟计算,分析窗墙比、体型系数、朝向三大因素对总供暖热负荷的影响,得到了兰州地区住宅建筑南偏西30°朝向与南偏东30°朝向、正南方向相比,总热负荷最小,但最大热负荷最大的结论,为南偏西建筑进行供热调节实现节能提供依据。南向墙面内凹的住宅建筑不宜通过面积热指标法来估算热负荷。     

低品位多热源联供热水系统的节能分析

以太阳能、空气源热泵和废水余热回收联合热水系统为例,介绍系统的构成及运行原理。分析计算全年四季3种热源的供热负荷及其在系统总热负荷构成中的占比,提出全年运行策略。理论分析与工程实际系统分析表明,低品位多热源热水联供系统更具节能潜力与应用推广优势。     

联合循环供热机组的热负荷计算方法研究

以燃气-蒸汽联合循环发电供热机组为例,给出以热用户“有效用热量”作为热负荷设计依据的概念.对比2种热负荷计算的结果,表明采用“有效热量”方法可正确地计算用户的用热负荷,并折算成热源点供热量,为节能工作提供指导.     

商业建筑空调节能技术探讨

针对建筑空调系统能耗的影响因素和商业建筑的特点,以商业建筑空调节能改造为例,从减少冷热负荷、提高冷热源效率、利用自然冷源、减少水泵电耗、减少风机电耗、改进气流组织等6个方面分析了商业建筑空调节能的具体技术措施和实施办法.     

商业建筑空调节能探讨

针对建筑空调系统能耗的影响因素和商业建筑的特点，以商业建筑空调节能改造为例，从减少冷热负荷、提高冷热源效率、利用自然冷源、减少水泵电耗、减少风机电耗、改进气流组织等6个方面分析了商业建筑空调节能的具体技术措施和实施办法。     

建筑节能新方向:太阳能光伏-地源热泵系统

减少我国冬季采暖所造成的大气污染,降低供暖系统的能耗,节约能源一直是建筑节能追求的目标.目前太阳能光伏发电已经成为人类利用太阳能的最主要方式之一,地源热泵已被作为一项旨在解决建筑冷热源问题的新技术,日渐受到人们的重视.将光伏转换与热泵循环有机结合在一起,从而形成了太阳能光伏-地源热泵系统.该系统提高了光电转换和光热吸收效率,光电/光热综合利用,极大地提高了单位面积太阳辐照的利用效率,同时可提高热泵系统在寒冷地区运行的适用性;利用光电效应把太阳能中高能带区域的光能直接转化成电能,可大大提高太阳能的可用能效率;在增加能量储存装置和逆变器的条件下,可以使系统脱离公用电网运行,从而增加了系统的适用性和灵活性;与普通的空气源热泵相比,太阳能地源热泵具有较高的热性能,具有一机多用的功效;与建筑物相结合的太阳能热泵系统,可以增加建筑物的隔热效果,起到减少建筑物冷暖负荷的作用,同时可极大地减少环境污染.     

Review on solar air heating system with and without thermal energy storage system

In order to produce process heat for drying of agricultural, textile, marine products, heating of buildings and re-generating dehumidify agent, solar energy is one of the promising heat sources for meeting energy demand without putting adverse impact of environment. Hence it plays a key role for sustainable development. Solar energy is intermittent in nature and time dependent energy source. Owing to this nature, PCMs based thermal energy storage system can achieve the more popularity for solar energy based heating systems. The recent researches focused on the phase change materials (PCMs), as latent heat storage is more efficient than sensible heat storage. In this paper an attempt has been made to present holistic view of available solar air heater for different applications and their performance.     

On the potential trade-offs between energy supply and end-use technologies for residential heating

In Sweden, where district heating accounts for a significant share of residential heating, it has been argued that improvements in end-use energy efficiency may be counter-productive since such measures reduce the potential of energy efficient combined heat and power production. In this paper we model how the potential trade-offs between energy supply and end-use technologies depend on climate policy and energy prices. The model optimizes a combination of energy efficiency measures, technologies and fuels for heat supply and district heating extensions over a 50 year period. We ask under what circumstances improved end-use efficiency may be cost-effective in buildings connected to district heating? The answer hinges on the available technologies for electricity production. In a scenario with no alternatives to basic condensing electricity production, high CO₂ prices result in very high electricity prices, high profitability of combined heat and power production, and little incentive to reduce heat demand in buildings with district heating. In contrast, in a scenario where electricity production alternatives with low CO₂ emissions are available, the electricity price will level out at high CO₂ prices. This gives heat prices that increase with the CO₂ price and make end-use efficiency cost-effective also in buildings with district heating.     

Discrete fourier series models for building auxiliary energy loads based on network formulation techniques

This paper presents a discrete Fourier series methodology for determining auxiliary energy loads in buildings. By applying network theory, flexible and efficient computer formulation techniques for the nodal frequency domain equations are developed. Two types of auxiliary sources are modelled; in the first one the room air temperature profile is specified, while in the second one an auxiliary heating/cooling source is modelled as a proportional control heat source. Unlike analytical frequency domain approaches such as those based on the Fourier transform, the discrete frequency domain methodology employed allows complex heat transfer mechanisms such as longwave radiant exchanges between room surfaces to be directly included in the formulation, and time-varying conductances such as that for a window with night insulation are also modelled. Thus, the methodology is particularly suitable for passive solar analysis.     

Towards the EU emissions targets of 2050: optimal energy renovation measures of Finnish apartment buildings

Member countries of the European Union have released targets to reduce carbon dioxide emissions by 80% by the year 2050. Energy use in buildings is a major source of these emissions, which is why this study focused on the cost-optimal renovation of Finnish apartment buildings. Apartment buildings from four different construction years (pre-1976, 1976–2002, 2003–2009 and post-2010) were modelled, using three different heating systems: district heating, ground-source heat pump and exhaust air heat pump. Multi-objective optimisation was utilised to find the most cost-effective energy renovation measures. Most cost-effective renovation measures were ground-source heat pumps, demand-based ventilation and solar electricity. Additional thermal insulation of walls was usually too expensive. By performing only the cost-effective renovations, the emissions could be reduced by 80%, 82%, 69% and 68%, from the oldest to the newest buildings, respectively. This could be done with the initial investment cost of 296, 235, 115 and 104?€/m², respectively.     

建筑形式对太阳能热利用的影响研究

以上海地区的住宅建筑为研究对象,通过模拟分析的方法,采用DeST软件计算确定建筑逐时的采暖、空调能耗,研究分析窗墙比对建筑全年采暖能耗、全年空调能耗以及全年采暖、空调总能耗的影响规律,研究分析太阳辐射热增加所导致采暖能耗的降低幅度与外围护结构保温性能两者之间的定量关系。计算结果表示在夏季外窗遮阳和夜间通风的条件下,加大南向窗墙比可增强太阳能的热利用效率,降低建筑全年的采暖、空调总能耗;而外围护结构保温性能的增强则可降低室内向室外散热的程度,相应提高对冬季太阳辐射的热利用程度,从而达到降低采暖能耗的目的。     

Global warming’s impact on the performance of GSHP

Since heating and cooling systems of buildings consume 30–50% of the global energy consumption, increased efficiency of such systems means a considerable reduction in energy consumption. Ground source heat pumps (GSHP) are likely to play a central role in achieving this goal due to their high energy efficient performance. The efficiency of GSHP depends on the ground temperature, heating and cooling demands, and the distribution of heating and cooling over the year. However, all of these are affected by the ongoing climatic change. Consequently, global warming has direct effects on the GSHP performance. Within the framework of current study, heating and cooling demands of a reference building were calculated for different global warming scenarios in different climates i.e. cold, mild and hot climate. The prime energy required to drive the GSHP system is compared for each scenario and two configurations of ground heat exchangers. Current study shows that the ongoing climatic change has significant impact on GSHP systems.     

几种供热热源的特点与能耗分析

介绍了热电联产、区域锅炉房、分散燃气锅炉房、单户式燃气炉和地下水源热泵等主要供热热源的特点,对比分析了各种热源形式供热系统的一次能源消耗量,并提出了供暖热源选择的优先顺序,为不同现状下新旧建筑的供热方式提供建议。     

The effects of internal gains on residential space-heating analyses

Analyses of the energy used for winter space heating in residences (and other buildings) often involve only the energy source used in the space-heating system. We demonstrate that serious errors can result from this approach, since the internal heat gains from other energy sources may play an important or dominant role in meeting the heating requirements. It is even possible for energy-conservation measures to lead to apparent increases in energy consumption if the analysis does not include all energy sources. Internal gains should also be considered in analyses of annual energy consumption.     

Comparison of energy and exergy analysis of fossil plant,ground and air source heat pump building heating system

The energy and exergy flow for a space heating systems of a typical residential building of natural ventilation system with different heat generation plants have been modeled and compared. The aim of this comparison is to demonstrate which system leads to an efficient conversion and supply of energy/exergy within a building system.The analysis of a fossil plant heating system has been done with a typical building simulation software IDA–ICE. A zone model of a building with natural ventilation is considered and heat is being supplied by condensing boiler. The same zone model is applied for other cases of building heating systems where power generation plants are considered as ground and air source heat pumps at different operating conditions. Since there is no inbuilt simulation model for heat pumps in IDA–ICE, different COP curves of the earlier studies of heat pumps are taken into account for the evaluation of the heat pump input and output energy.The outcome of the energy and exergy flow analysis revealed that the ground source heat pump heating system is better than air source heat pump or conventional heating system. The realistic and efficient system in this study “ground source heat pump with condenser inlet temperature 30 °C and varying evaporator inlet temperature” has roughly 25% less demand of absolute primary energy and exergy whereas about 50% high overall primary coefficient of performance and overall primary exergy efficiency than base case (conventional system). The consequence of low absolute energy and exergy demands and high efficiencies lead to a sustainable building heating system.