太阳能热水系统节能率与设计参数的探讨

Study on energy saving rate and design parameters of solar hot water system

太阳能热水系统的能耗主要为辅热系统的能耗,其节能率与系统设计保证率呈正相关。通过分析太阳辐照量与生活热水耗热量的关系可知,选取节能率变化曲线偏离点处的太阳能保证率可避免出现热量浪费和一次投资过大,保证较高的经济效益。选取了长沙地区的3种典型的设置集中热水供应系统的建筑进行分析,依据长沙地区的气象参数和此三类建筑生活热水耗热量的变化特征,得出各自节能率变化曲线偏离点处的太阳能保证率的取值。同时,根据公式计算了长沙地区平板型太阳能集热器的年平均集热效率;推导了q_(rid)值的计算方法并推荐了在长沙地区的取值。

The energy consumption of solar hot water system is mainly the energy consumption of auxiliary heating system,and its energy saving rate is positively correlated with design solar fraction of the system.Via analyzing the relationship between solar radiation and heat consumption of domestic hot water,it can be concluded that selecting the solar fraction at the deviation point of the energy sav-ing rate change curve can avoid heat waste and excessive investment,ensuring high economic benefits.Three typical buildings with central hot water supply system in Changsha were selected for analysis.Based on the meteorological parameters in Changsha and the changes in heat consumption of domestic hot water in these three types of buildings,the values of solar fraction at the deviation points of their respective energy saving rate curves were obtained.Meanwhile,the annual average heat collection effi-ciency of flat plate solar collectors in Changsha was calculated based on formulas;Derived the calcula-tion method for value and recommended values in Changsha.