地源热泵在室内游泳池供暖空调中的应用研究

在分析了地源热泵系统的特点和室内游泳池的冷热负荷概算的基础上，提出了采用地源热泵系统可同时满足室内游泳池的供暖、空调及池水加热3项需求；分析了不同季节地源热泵在游泳池的运行工况。通过分析表明，地源热泵系统的运行费用比传统的冷水机组加燃油锅炉系统可节省费用约50％，比冷水机组加燃气锅炉系统可节省费用21％。     

郑州市某园区地源热泵经济性能分析

将郑州市某一园区的螺杆冷水机组+锅炉系统替换为中深层地下水+两级板式换热器+双效热泵机组的地源热泵系统,地源热泵系统具有良好的性能,分析两套系统的经济性,利用静态回收期的分析方法对两套系统的初始投资费用和年运行费用进行比较。结果显示：地源热泵系统的初始投资比螺杆冷水机组+锅炉系统高约443.1万元,年运行费用比螺杆冷水机组+锅炉系统低约95.5万元,约4.6年之后螺杆冷水机组+锅炉系统的总投资金额可追平地源热泵系统的总投资金额。研究表明,从长期投资回报率分析,与螺杆冷水机组+锅炉系统相比,地源热泵系统具有更高的经济性和节能性。     

地源热泵在温水游泳池系统中的应用研究

结合室内温水游泳池的实际运行负荷工况,引进地源热泵技术,在集中热泵主机全部102kW功率完成泳池初次加热之后,实现每天对游泳池160万kcal的热损补偿,解决游泳池所存在的热源问题,同时对温水游泳池采用地源热泵系统的经济性进行分析,与传统加热方式相比,可节能50%以上。     

严寒地区污水源热泵系统节能潜力的分析

本文将一个位于长春市的以原生污水为冷热源的污水源热泵系统工程选为研究对象,通过与传统的集中供热+水冷冷水机组系统进行能耗对比从而进行节能性分析.通过对运行数据的监测及整理,结果表明相较于传统的集中供热+水冷冷水机组系统,该系统夏季节省2480 kg标煤,节能率40.19％、冬季节省5200 kg标煤;节能率22.13％...     

基于热回收的游泳池热泵除湿供暖系统

基于国内室内游泳馆能耗较高且大部分未设热回收装置的现状，讨论了利用热泵对游泳池供暖除湿的同时实现废热回收的系统设计方案以及回收效果，提出了利用太阳能辅助热泵运行的思想，并给出联合运行的设计方案。从能源利用的角度对二者进行了分析，并与常规的锅炉加冷水机组系统进行了经济性分析和比较，阐明将热泵应用于游泳池除湿供暖，不仅可以有效地节约能源，而且在经济上也是一个非常可行的方案。     

变频技术在污水源热泵系统中的应用研究

在污水源热泵供暖空调系统中,热泵机组大部分时间都是处于部分负荷运行中,而污水泵和中介水泵却一直处于满负荷运行,不能随着热泵机组负荷的变化而进行调节,结果造成了系统耗电量的大量增加。为了减少污水源热泵系统中水泵的耗电量,节省运行费用,采用理论分析和实验测量的方法,确定北京某宾馆污水源热泵系统冷热源部分水泵的变频范围和变频前后整个夏季制冷期的耗电量,研究水泵变频调速供水的节能效果和经济性。研究表明,系统冷热源部分水泵采用变频调速技术后,整个夏季供冷期节省电量65136kwh,节省运行费用5．6万元。在污水源热泵供暖空调系统中,水泵采用变频调速技术,可明显地节省运行费用,带来显著的经济效益。     

污水源热泵技术及其应用

介绍了污水源热泵的特点。通过对空气源热泵、地源热泵和污水源热泵等不同采暖系统的经济性和环保效果分析显示，污水源热泵系统的初投资为地源热泵的70％左右。综合考虑初投资和运行费用等因素，污水源热泵系统的经济效果和环保效果最为显著。     

长沙市某酒店污水源热泵应用可行性分析

为了了解污水源热泵系统在长沙市的适用情况,对污水的相关特性进行了计算分析。基于工程实践数据,精确计算了长沙市城市污水中可利用的能量,定量比较了污水源热泵系统与常规冷热源系统的节能性能。研究表明:长沙市城市污水中储存的可利用热量很高,在相同的供热量和制冷量的条件下,污水源热泵空调系统比水冷离心式冷水机组+燃气锅炉系统更节能,年运行费用总计可节约152.14万元,静态投资回收期为6.6年;由此认为长沙地区的污水源热泵的应用有巨大潜能。     

地源热泵系统动态经济性分析

介绍地源热泵系统的基本原理,分析地源热泵技术的应用背景。利用费用现值法和年值法对地源热泵系统和空气源热泵系统的经济性进行计算,运用动态追加投资回收期公式得出地源热泵系统初投资的动态追加投资回收期。实例分析表明：地源热泵系统比传统空调系统运行费用低,具有明显的节能环保功效。     

水蓄能地源热泵系统的一种在线优化运行控制

以水蓄能地源热泵系统为研究对象,通过理论与实验相结合的手段,对该系统进行在线优化运行控制的理论分析与实验研究。研究结果表明:在线优化运行控制能有效提高系统的运行效率,相对于地源热泵独立直接供能系统,应用优化运行控制后,大区间变容量运行热泵的性能系数可从3.0最大增至约4.5,同时在峰谷电价的基础上可为用户节省大量运行费用,日运行费用的节省比例(节费率)约为21.8%,可为在线优化运行控制技术在工程应用中的推广提供数据支持。     

地源热泵的优越性及前景展望

介绍了地源热泵的工作原理，并通过比较地源热泵与传统空调系统的运行费用，说明了地源热泵在运行费用方面具有较大优势。虽然地源热泵的应用受到一些制约因素的影响，但作为一项节能新技术，地源热泵必将拥有广阔的应用前景。     

Energy-conservation measures for indoor swimming pools

We present a methodology for estimating heat losses for indoor swimming pools and energy savings associated with the adoption of selected energy-conservation strategies and devices in natatoriums. Although results are given for selected geographic locations, the methodology is generally applicable. Energy-conservation measures that reduce ventilation requirements are the most effective in decreasing energy costs for heating natatoriums. Pool covers are shown to save energy when the installation is accompanied by lower ventilation rates. At the present time, commercially available solar pool-heating systems are not economical for the climate of St. Louis compared to heating with natural gas but are marginally competitive with oil-fired heating systems.     

An integrated 3D approach to assess the geothermal heat-exchange potential: The case study of western Sicily (southern Italy)

This paper presents a multidisciplinary methodology to estimate the underground heat-exchange potential for Borehole Heat Exchangers (BHEs) coupled with Ground Source Heat Pumps (GSHPs) over wide areas. The proposed methodology was tested in four sites in western Sicily (southern Italy) where the shortage of subsurface geological data, in addition to the undefined authorization processes for this kind of system, is probably the main barrier to planning and exploiting geothermal heat for heating and cooling purposes. Reliable high-resolution 3D geological and petrophysical models were built based on the integration of airborne electromagnetic data and laboratory measurements of the thermal properties of rock samples. A GIS-based procedure was applied to assess the geothermal heat-exchange potential using 3D models of thermal conductivity as the main input. The results of the analyses are represented by thematic maps of the underground heat exchange potential for BHEs coupled with GSHPs. The study areas show a generally high suitability for the use of this technology and several municipalities in the area could take advantage of the resulting maps for energy planning.     

Heating requirements in greenhouse farming in southern Italy: evaluation of ground-source heat pump utilization compared to traditional heating systems

Greenhouse farming, where energy consumptions are mainly related to the greenhouses heating, is one of the sectors consuming the most energy in the agricultural industry. High costs and the uncertain availability of fossil fuels constrain the use of heating applications. Among possible solutions, the utilization of renewable heating systems such as geothermal energy through ground-source heat pump systems (GSHPs) at competitive prices has to be taken in consideration. The competitiveness of these systems depends mainly on the characteristics of the end-users, i.e., the annual heating loads. Few studies focusing on the potential of using these systems start with an analysis of the thermal requirements and end with a cost evaluation in tune with local assets, geo-climatic conditions, and landscape protection. This paper analyzes the greenhouse crop industry in the Apulia region in southern Italy, as a potential end-user of GSHP systems. Data collected from an area mainly devoted to greenhouse crop production have been used to (a) describe greenhouse farms, (b) define the heating requirements of a greenhouse model representative of the most used typology in the investigated area, and (c) examine the economic viability of greenhouse heating with GSHP systems. Both vertical and horizontal ground heat exchanger (GHE) configurations are compared with conventional fossil-fuel heating systems. In all scenarios considered, the observed payback periods appear reasonable and worthy of consideration. The results suggest that these technologies can fully satisfy the winter heating requirements in a cost-effective way and they can support the planning of measures aimed to improve the sector competitiveness.     

Thermoeconomic assessment of a multi-engine,multi-heat-pump CCHP (combined cooling,heating and power generation) system – A case study

Design and operation of complex systems for combined cooling, heating and power generation (CCHP) are always a matter of matching performance and demand characteristics of a thermal system set to supply electrical, cooling and heating loads, according to specific usage demands. Equipment selection and operation require the characterization of power, heating and cooling load demands, and their time variation during years, seasons, months and even hours or minutes. The paper aims at utilizing a general model for complex CCHP systems. The proposed model is based on the general theory of exergy cost and structural coefficients of internal links. A general model is presented, and a simple hypothetical cogeneration case is studied. The system operates with two heat engines, with waste heat recovery driving a chiller, in order to meet electrical power and refrigeration loads.     

Research on improving energy efficiency and the annual distributing structure in electricity and gas consumption by extending use of GEHP

The gas engine-driven heat pump (GEHP), which has been considered as a preferable choice in the heating and air-conditioning scheme can make full use of the waste heat from the engine and achieve a higher primary energy ratio (PER) than other forms of heating/cooling systems. In this paper, the relationship between the capacity characteristic of the GEHP and the heating and cooling loads of buildings has been analyzed. Meanwhile the reasons of the imbalance of the urban electricity and natural gas consumptions between summer and winter have been studied. The running characteristic of a water-to-water GEHP has been investigated experimentally and the PER was measured. Based on the analysis and experimental results, it could be concluded that if both the gas-fired boilers and electric air conditioners are replaced by GEHPs in some percentage, we can narrow the gaps between the requirement and provision of electricity and natural gas and balance the seasonal consumption differences of electricity and natural gas between summer and winter simultaneously. In order to improve energy efficiency, environmental quality and energy consumption structure effectively, the governmental incentive policies for promoting use of GEHPs should be formulated in China and some other developing countries.     

Design parameters and control strategies for a combined passive heating and cooling system in Louisville,KY

ABSTRACT

Conventional passive solar systems can significantly reduce a building's heating load. However, the integration of passive heating and cooling systems in the same building and the benefits of actively controlling passive systems has largely been unexplored. The objective of this study was to determine the relative performance of a passive solar heating and sky cooling system operating with a range of control strategies, with the goal of minimising the overall annual energy use for space conditioning. A combined system (CS) and a separate system (SS) were simulated with thermal networks using MATLAB, with weather data for Louisville, KY. The control strategies simulated included: Seasonal, Ambient, Room and Matrix. The highest fraction of energy supplied by ambient sources for the SS was 0.707 with Matrix control, while for the CS, the highest fraction (0.704) was with Matrix temperature control with switchable attributes for heating and cooling.     

Performance and economic feasibility of ground source heat pumps in cold climate

Ground source heat pumps (GSHP) are attractive alternatives to conventional heating and cooling systems owing to their higher energy utilization efficiency. In this paper, the effect of various system parameters on GSHP performance is studied using a computer model. Also, a comparative economic evaluation is carried out to assess the feasibility of using a GSHP in place of conventional heating/cooling systems and an air source heat pump. The results indicate that system parameters can have a significant effect on performance, and that GSHP is economically preferable to conventional systems. © 1997 John Wiley & Sons, Ltd.     

A study of the potential of using the Earth to air heat exchanger for cooling and heating of residential buildings in Iraq

The Earth to air heat exchanger (EAHE) is an effective passive cooling and heating system for buildings. This paper studied numerically the potential for reduction in energy consumption for cooling and heating loads for a residence equipped with an EAHE system in the climate of Nasiriya city, which is located in southern Iraq and at 31.7°N and 45.8°E, latitude and longitude, respectively. Also, this paper presents a study about the thermal performance of three types of EAHE systems, system 1, consisting of one layer of EAHE and buried at an available area of house garden with 3‐m depth, system 2, at the same site of system 1, but with two layers of EAHE at two depths, 3 and 4 m, and finally, system 3, buried along the area of the house at a depth of 3 m. First, the built numerical model was validated against experimental results, and the results of the comparison showed good agreement. The electricity consumption for cooling and heating of the house is calculated with and without the EAHE system. The results showed that with using EAHE, there is a considerable saving in energy and saving in the cost of electricity consumption, which reached 376 329 IQD ($301.11) over 1 year for system 2.     

Use of solar assisted geothermal heat pump and small wind turbine systems for heating agricultural and residential buildings

The main objective of the present study is twofold: (i) to analyze thermal loads of the geothermally and passively heated solar greenhouses; and (ii) to investigate wind energy utilization in greenhouse heating which is modeled as a hybrid solar assisted geothermal heat pump and a small wind turbine system which is separately installed in the Solar Energy Institute of Ege University, Izmir, Turkey. The study shows 3.13% of the total yearly electricity energy consumption of the modeled system (3568 kWh) or 12.53% of the total yearly electricity energy consumptions of secondary water pumping, brine pumping, and fan coil (892 kWh) can be met by using small wind turbine system (SWTS) theoretically. According to this result, modeled passive solar pre heating technique and combined with geothermal heat pump system (GHPS) and SWTS can be economically preferable to the conventional space heating/cooling systems used in agricultural and residential building heating applications if these buildings are installed in a region, which has a good wind resource.