关键词:冰蓄冷 逐时冷负荷 模拟 蓄冷量比例 经济性
Chengdu some commercial project feasibility analysis of ice storage air conditioning system
By Zhang Ye and Liu Ye
Abstract:This article in view of the chengdu area a commercial project of ice storage system design, the all-year hourly air conditioning cooling load simulation, on the basis of considering the ice storage system under different operating mode (melting ice cooling, direct cooling) efficiency, combining with local electricity price policy, cool storage system by calculation using different cool storage quantity proportion of economy and the whole life cycle cost, study the effect of the project adopts ice storage system as well as the optimal amount of cool storage configuration, auxiliary ice storage options.
Keywords:Ice storage,The hourly cooling load,Simulation,Cold storage quantity proportion,Economy
Building energy conservation research center,tsinghua university
1项目概况
项目位于成都市中心,地下共三层,地上4层,地下三层和地下二层为车库和设备机房,地下一层至地上4层为商业(包含商铺、餐饮、超市),建筑面积共为122307m2。
成都地区商业建筑实行分时电价,出于节省运行费用的考虑,考虑采用冰蓄冷空调系统。本项目商业区空调末端采用常规风机盘管和空调箱为主,设计供回水温度为7/12℃,参照文献1,拟采用图1所示的冰盘管蓄冷、乙二醇溶液为载冷剂的内融冰系统,系统可实现双工况冷机制冰工况、蓄冰装置融冰供冷工况、双工况冷机单独供冷工况、双工况冷机和蓄冰装置同时供冷工况。
图1 冰蓄冷系统设计示意
2问题分析
尽管冰蓄冷系统利用谷电制冰蓄冷时,可以节约制冷电费,但与常规制冷方案相比,冰蓄冷运行过程中,实际消耗的电量会大大增加,主要原因如下:1.制冷机在制冰工况时制冷效率低,采用双工况冷机白天直接供冷时效率也偏低;2.增加了乙二醇泵电耗,图1所示的冰蓄冷系统,蓄冰槽蓄冷和放冷过程均需开启乙二醇泵,双工况冷机直接供冷时也需要开启乙二醇泵;3.使用过程中蓄冷装置会有能量损失。表1给出了图1所示冰蓄冷系统与常规离心冷机系统在制冷效率上的对比,冰蓄冷系统在融冰工况的制冷效率仅为常规制冷系统的67%,冰蓄冷系统在双工况冷机直接供冷时的效率仅为常规制冷系统的83%,同样制冷量情况下,融冰供冷比常规制冷多消耗50%电能,双工况冷机直接供冷比常规制冷多消耗21%电能,可见冰蓄冷空调运行时实际消耗的电能远高于常规制冷方案。