Numerical Study on the Suitability of Passive Solar Heating Technology Based on Differentiated Thermal Comfort Demand

Indoor thermal comfort and passive solar heating technologies have been extensively studied.However,few studies have explored the suitability of passive solar heating technologies based on differentiated thermal comfort demands.This work took the rural dwellings in Northwest China as the research object.First,the current indoor and outdoor thermal environment in winter and the mechanism of residents’differentiated demand for indoor thermal comfort were obtained through tests,questionnaires,and statistical analysis.Second,a comprehensive passive optimized design of existing buildings was conducted,and the validity of the optimized combination scheme was explored using DesignBuilder software.Finally,the suitability of passive solar heating technology for each region in Northwest China was analyzed based on residents’differentiated demand for indoor thermal comfort.The regions were then classified according to the suitability of the technology for these.The results showed that the indoor heating energy consumption was high and the indoor thermal environment was not ideal,yet the solar energy resources were abundant.Indoor comfort temperature indexes that match the functional rooms and usage periods were proposed.For the buildings with the optimized combination scheme,the average indoor temperature was increased significantly and the temperature fluctuation was decreased dramatically.Most regions in Northwest China were suitable for the development of passive solar heating technology.Based on the obtained suitability of the technology for the regions of Northwest China,these were classified into most suitable,more suitable,less suitable,and unsuitable regions.

Intelligent Agent-Based Architecture for Demand Side Management Considering Space Heating and Electric Vehicle Load

Contraction of resilience on generation side due to the introduction of inflexible renewable energy sources is demanding more elasticity on consumption side. It requires more intelligent systems to be implemented to maintain power balance in the grid and to fulfill the consumer needs. This paper is concerned about the energy balance management of the system using intelligent agent-based architecture. The idea is to limit the peak power of each individual household for different defined time regions of the day according to power production during those time regions. Monte Carlo Simulation (MCS) has been employed to study the behavior of a particular number of households for maintaining the power balance based on proposed technique to limit the peak power for each household and even individual load level. Flexibility of two major loads i.e. heating load (heat storage tank) and electric vehicle load (battery) allows us to shift the peaks on demand side proportionally with the generation in real time. Different parameters related to heating and Electric Vehicle (EV) load e.g. State of Charge (SOC), storage capacities, charging power, daily usage, peak demand hours have been studied and a technique is proposed to mitigate the imbalance of power intelligently.

Space heating and hot water demand analysis of dwellings connected to district heating scheme in UK

To achieve CO2 emissions reductions,the UK Building Regulations require developers of new residential buildings to calculate expected CO2 emissions arising from their energy consumption using a methodology such as Standard Assessment Procedure(SAP 2005) or,more recently SAP 2009.SAP encompasses all domestic heat consumption and a limited proportion of the electricity consumption.However,these calculations are rarely verified with real energy consumption and related CO2 emissions.This work presents the results of an analysis based on weekly heat demand data for more than 200 individual flats.The data were collected from a recently built residential development connected to a district heating network.A method for separating out the domestic hot water(DHW) use and space heating(SH) demand has been developed and these values are compared to the demand calculated using SAP 2005 and SAP 2009 methodologies.The analysis also shows the variation in DHW and SH consumption with size of flats and with tenure(privately owned or social housing).Evaluation of the space heating consumption also includes an estimate of the heating degree day(HDD) base temperature for each block of flats and compares this to the average base temperature calculated using the SAP 2005 methodology.

考虑含HRD的光热电站和综合需求响应的综合能源系统低碳经济调度

在“双碳”的背景下,为进一步提升综合能源系统(Integrated Energy System, IES)的经济性和环境效益,文中提出一种在奖惩阶梯型碳交易机制下考虑含热回收装置(Heat Recycling Device, HRD)的光热电站和综合需求响应的IES系统低碳经济调度方法。首先,在源侧构建含热回收装置的光热电站与加装碳捕集的热电联产机组联合运行的IES架构,并分析电转气两阶段的运行原理,建立计及余热回收的电转气设备模型。其次,考虑到负荷侧电、热、气三种负荷的柔性特性,在负荷侧建立电热气综合需求响应模型。最后,引入奖惩阶梯型碳交易机制,进一步减小系统碳排放量,构建调度周期内以含购能成本、运维成本、碳交易成本等系统总运行成本最小为目标的综合能源系统低碳优化调度模型。通过算例分析结果表明,所提方法不仅能提高机组的运行潜力,而且有效降低了系统总运行成本与碳排放量。

计及需求响应的光热电站参与深度调峰的分层优化调度策略

从源、荷两侧挖掘系统调峰潜力,建立计及需求响应的光热电站参与深度调峰的分层优化调度模型。上层从负荷侧出发,提出一种基于负荷分类的价格需求响应模型,可有效缓解系统调峰压力;中层从电源侧出发,利用光热电站灵活的调节特性在深度调峰时段协调火电机组参与辅助调峰,构建以运行总成本最小为目标函数的日前调度模型;下层提出一种基于模型预测控制的日内动态调整模型,在滚动优化的同时,通过状态反馈环节实时调整光热电站储热装置充放热修正日前调度计划。仿真结果表明,所提调度策略在降低系统调峰成本的同时能有效抑制风光以及负荷的短时功率波动,在保证系统安全稳定运行的前提下提升风光消纳率。

基于典型气象数据分析的南北方 供暖特性研究

针对南、北方供暖的需求差异,基于历年气象数据,综合考虑累年最冷月平均温度、供暖度日数HDD18、供暖期天数等多种因素,分析了中国南、北方8个典型城市的气候特征;同时结合需求调研和温度分布、波动差异对比情况,讨论了不同地区热负荷动态特性及负荷求解宜使用的方法;分析总结了南、北方地区的系统运行特征情况,给出了关于供暖系统设计、系统形式、运行策略的建议;并通过实际案例具体分析了供暖系统设置的适宜性问题,为后续供暖设计方法、参数确定,供暖方式选择和系统设置提供基础。

考虑氢储能和需求响应的综合能源系统双层优化配置

在双碳目标下,为改善综合能源系统功率不平衡,提高能源运营商收益,降低用户购能成本,首先,结合氢储能可作为源-荷-储的优点以及电制热的能源转换特性,设计了考虑氢储能的综合能源系统双层框架。其次,根据两种不同时间尺度,提出了一种考虑负荷侧需求响应和含电制热设备用户群的综合能源系统氢储能双层优化配置模型,上层模型结合氢储能特性进行长时间尺度优化配置;下层模型利用需求响应和电制热设备对用户群负荷进行优化,以求解短时间尺度含氢储能综合能源系统优化运行问题。再次,采用KKT条件和Big-M法将模型转为单层线性问题。最后,结果显示,通过配置氢储能以及采用电制热设备和需求响应,可提高运营商收入和新能源消纳,降低用户群成本,减少功率失衡风险。

考虑阶梯式碳交易与电热需求响应的综合能源系统经济调度

在能源安全新战略背景下,推动可再生能源发展、降低碳排放将是未来发展趋势。为了消纳大规模风电的弃风功率以提升电网的调峰能力,首先考虑阶梯式碳交易机制,采用碳交易市场,利用碳交易价格达到控制碳排放的目的;其次基于分时电价形成用户用电舒适度与用热舒适度,构建电热负荷需求响应模型,在掌握电锅炉、储热装置和热需求可时移特性的基础上,通过风电供给价格弹性系数描述风电出力与电锅炉协议电价之间的变化;最后通过综合满意度指标评估负荷响应能力,构建了考虑需求响应和阶梯式碳交易机制的含蓄热式电锅炉综合能源系统优化调度模型,实现系统经济运行,并采用CPLEX求解器对所构建模型进行求解。结果表明所提方法能够有效促进风电消纳,减少碳排放量且有效降低系统运行成本。

一种月面微型热管堆电源概念设想

未来月球科研站建设及月面探测等任务需解决长期稳定能源及电力供给问题,受月面复杂环境影响,月面能源供给挑战极大。核反应堆电源具有长寿命、全天候、环境耐受力强等优势,是解决月面任务长期能源需求的理想选择,热管冷却型反应堆作为一种新型反应堆电源具有系统简单、结构紧凑、可靠性高等特点,且易于实现长寿命设计。针对目前月面能源问题,提出了采用500 W电功率月面微型热管堆电源供电的初步设想,并重点对其屏蔽设计及辐射防护问题进行了研究,提出了相关屏蔽设计方案及辐射防护措施。经过初步屏蔽设计研究,该电源可采用移动式、月面固定点位布置及浅坑式布置多种方式为月面用电设备供电,质量可约束在500 kg左右,轻质且微型,为科研站月面核反应堆电源屏蔽设计提供了思路。

基于AA-CAES电站和综合需求响应的供暖期弃风消纳策略

“双碳”目标背景下,为解决热电联产机组“以热定电”模式导致的大规模弃风问题,本文提出基于先进绝热压缩空气储能电站(advanced adiabatic compressed air energy storage,AA-CAES)和综合需求响应的综合能源系统(integrated energy system,IES)供暖期弃风消纳策略。首先,在“源-储”两侧建立热电联产机组与AA-CAES电站耦合运行模型,分析耦合运行实现热电解耦机理;其次,在“荷”侧引入价格型和替代型需求响应机制来探寻负荷侧优化系统调度潜力;然后,在IES中引入碳捕集系统和阶梯型碳交易机制来约束碳排放,并在碳排放量最少、综合成本最低为目标构建IES运行基础上,引入模糊机会规划约束模型来分析风、光不确定性对系统调度影响;最后,利用西北某地区实际数据进行算例验证。结果表明:热电机组与AA-CAES电站耦合运行相较于未耦合运行可提高风电消纳率84.55%、降低总成本11.42%、减少碳排放20.28%;综合需求响应机制的引入可进一步提高风电消纳率35.00%、降低总成本20.93%、减少碳排放24.43%;风光不确定性的上升会提高与外部电网的交互成本。

电-热-氢综合能源系统鲁棒区间优化调度

储能技术与风电相结合实现电能的时空平移是解决系统运行稳定性问题的有效手段。氢储能具有储存容量大、可实现电热联产联供的优点,具有很大的发展潜能。然而由于风电存在不确定性,氢储能系统在频繁切换工作模式时面临着不确定的热能需求。因此,文中综合考虑氢储能在间歇模式下的热能需求,首先,介绍了氢储能系统接入的电-热综合能源系统基本结构,将风电场与氢储能相结合构成风-氢混合系统;然后,提出考虑风-氢混合系统热平衡需求不确定性的电-热综合能源系统鲁棒区间优化调度模型;最后,基于对偶理论,对所提出的模型转化求解,通过算例对比分析各类情况优化结果,验证了氢储能在促进风电消纳、提高系统能源综合利用率方面的有效性,并证明了考虑电解槽和燃料电池工作温度能提高系统的工作效率并提高风电场并网功率。

基于源荷储灵活资源协同的电热综合能源系统实验平台

当前能源转型背景下,发展综合能源系统是实现“碳达峰、碳中和”以及新型电力系统建设目标的重要途径。针对含多元化灵活资源的电热耦合系统,提出考虑“源-荷-储”协同的电热综合能源系统实验平台构建方案。设计考虑热电联产机组、电制热装置、蓄热罐以及电/热需求响应协同优化调度的实验案例,探讨实验平台在基础教学和拓展科研方面的用途。实验平台的建设为电气工程专业学生参与项目训练和创新实践类活动提供了重要的实践平台,有助于激发科研人员的探索性、创新性思维,促进理论研究和实验仿真的有机结合与良性循环,为综合能源系统领域的研究提供有力支撑。

蓄热式电采暖参与消纳受阻风光的源荷协调滚动调度

蓄热式电采暖负荷具有时移性和连续可调性,可作为需求侧资源解决乡村地区新能源消纳困难与清洁供暖问题。当前实施的峰谷分时电价,不能根据源荷变化有效引导电采暖运行以消纳受阻风光。因此提出采用场景法描述风光荷的不确定性,根据源荷峰谷时段变化确定分时电价。并且考虑电采暖响应分时电价时出现用电同时率高问题,引入需求价格弹性系数,建立以蓄热式电采暖运行成本和系统负荷峰谷差期望最小的日前日内源荷协调优化模型,滚动调整每时段各灵活资源出力。最后,通过仿真验证模型的有效性。

基于需求响应的电热综合能源市场MPEC优化

为促进电热综合能源市场多能流协同消纳,减少负荷不平衡所带来用能波动的问题,基于价格弹性矩阵建立电、热需求响应模型,以能量枢纽为利益主体,利用均衡约束数学规划模型,制定综合能源市场竞标策略。实现电、热网运营商运行成本最小的同时,使能量枢纽运营主体获得最大收益,并且有效降低系统总耗能。结果表明,系统在综合需求响应机制的作用下削峰填谷、平衡系统用能,以能量枢纽获益降低160.44元为代价,换取减少能耗2.3 MW,且冬夏两季能量枢纽收益和系统整体能耗百分比变化较小,分别为3.42%和0.604%。

智慧供热技术在城市集中供热系统的应用分析

智慧供热是将供热生产、供热输出、供热信息控制与传统集中供热的有机结合,以供热管网水力信息、室温采集为主题,实现了一种新型的智慧供热系统。将系统控制、水力信息、控制云平台一体化,达到数据采集智能化、系统调控自动化、运营监管化,达到供热稳定、高效节能、绿色环保的最大目的。随着我国城镇集中供热区域和供热规模的不断增大,供热方式日趋复杂化,对供热企业的运营和经营管理也提出了更高的需求,而智慧供热技术的发展,为实现“均衡输送、按需供热”的城市集中供热管网建设,起到了很好的支撑作用。

考虑电-气-热耦合和需求响应的虚拟电厂优化调度策略

热电联产机组以热定电的工作方式无法同时满足冬季供暖效率最大化和电力调峰需求,存在发电出力调节能力不足的问题。针对上述问题,提出了考虑电、气、热能源耦合特性以及需求响应的虚拟电厂优化调度策略。首先,为提升热电联产机组向下调峰能力,引入电制气设备和碳捕集技术,构建新型的热电联产耦合模型。其次,为提升系统运行的灵活性,考虑峰谷分时电价、热价,建立综合需求响应机制。然后,为减少系统发电成本,引入电、热储能装置,以系统总成本和电、热储能运行成本最小化为目标建立虚拟电厂双层优化模型,并根据下层优化模型的KKT(Karush-Kuhn-Tucher,KKT)条件将双层模型转为单层并线性化处理进行求解。结果表明,所提方法的碳排放、运行成本以及新能源消纳率达到最优,提升了热电机组向下调峰能力,满足了系统低碳性、经济性的需求。

基于铁路需求侧温度响应的供热系统节能运行策略研究

目的为了解决铁路站区供热系统供热量与各功能建筑需求热量不平衡而导致的能源严重浪费问题,方法提出铁路站区供热系统热源侧与建筑物联动调节的时空差异化运行策略,以响应站区内各建筑室内温度变化需求。首先,分析常规热源侧和建筑物侧运行调节策略,在此基础上研究时空差异化运行策略;其次,以大同某铁路站区供热系统为例,利用Simulink建立供热系统仿真模型;最后,在验证模型有较高准确性的基础上,对比分析3种不同运行策略下系统室内温度动态响应和能耗。结果与热源气候补偿质调节和建筑量调节运行策略相比,热源侧与建筑物联动调节的时空差异化运行策略不仅实现了不同建筑分时分温供热的需求,还有效减小了正常供热时间段和低温供热时间段室内温度波动幅度,提高了室内热舒适性。同时与系统无运行调节相比,热源质调节运行策略节能率为20.7%,建筑物量调节运行策略节能率仅为17.5%,时空差异化运行策略节能率达38.5%。结论本文提出的热源侧与建筑物联动调节的时空差异化运行策略能够满足铁路站区内不同功能建筑的室内变温需求,减小室内温度波动幅度,具有良好的节能效果。

计及动态能源价格和共享储能电站的多主体综合能源系统双层优化调度策略

可再生能源不确定性背景下,为协调综合能源运营商、电热负荷聚集商及共享储能电站之间的利益关系,提出一种电热综合动态定价机制,基于综合需求响应特性,引导电热负荷聚集商参与综合能源系统运营商优化,促进储能高效应用和新能源就地消纳,实现多利益主体互利共赢。以综合能源系统运营商为主体,以电热负荷聚集商和共享储能运营商为从体,构建一主多从的综合能源多运营主体系统优化模型。充分挖掘共享储能运营商的运行模式,包括充电、放电和提供备用等模式。采用CPLEX对主从博弈模型迭代求解,算例结果验证了模型及方法的有效性。

Freezing on demand: A new concept for mine safety and energy savings in wet underground mines

The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation areas.This mode of operation requires a massive amount of energy to sustain the thickness of the frozen body.Therefore,it is of great interest to propose new concepts to reduce energy consumption while providing sufficient structural stability and safe operation.This paper discusses the principle of the freezing on demand(FoD)by means of experiment and mathematical model.A lab-scale rig that mimics the AGF process is conceived and developed.The setup is equipped with more than 80 thermocouples,flow-meters,and advanced instrumentation system to analyze the performance of the AGF process under the FoD concept.A mathematical model has been derived,validated,and utilized to simulate the transient FoD concept.The results suggest that the overall energy saving notably depends on the coolant’s temperature;the energy saving increases while decreasing the coolant inlet temperature.Moreover,applying the FoD concept in an AGF system leads to a significant drop in energy consumption.

A Model for Regional Energy Utilization by Offline Heat Transport System and Distributed Energy Systems—Case Study in a Smart Community, Japan

Under the Kyoto Protocol,Japanwas supposed to reduce six percent of the green house gas (GHG) emission in 2012. However, until the year 2010, the statistics suggested that the GHG emission increased 4.2%. What is more challenge is, afterFukushimacrisis, without the nuclear energy,Japanmay produce about 15 percent more GHG emissions than1990 inthis fiscal year. It still has to struggle to meet the target set by Kyoto Protocol. The demonstration area of “smart community” suggests Japanese exploration for new low carbon strategies. The study proposed a demand side response energy system, a dynamic tree-like hierarchical model for smart community. The model not only conveyed the concept of smart grid, but also built up a smart heat energy supply chain by offline heat transport system. Further, this model promoted a collaborative energy utilization mode between the industrial sector and the civil sector. In addition, the research chose the smart community inKitakyushuas case study and executed the model. The simulation and the analysis of the model not only evaluate the environmental effect of different technologies but also suggest that the smart community inJapanhas the potential but not easy to achieve the target, cut down 50% of the CO2 emission.