一体化集热屋面太阳能空气供暖的技术经济性

Technical Economy of Integrated Collector Roof Solar Air Heating

针对北京村镇单层民用住宅(建筑面积为74 m^2),设计建造采用一体化集热屋面的太阳能空气供暖系统。介绍太阳能空气供暖系统的主要装置、系统流程与运行模式,对集热屋面、地面混凝土蓄热层(以下简称蓄热层)的做法进行详述。在自动控制模式(全天供暖)下,以2017年12月14日—15日、20日—21日、27日—28日、30日—31日作为测试日(分别定义为测试日1～4,测试时间为当日8:00至次日8:00),对各测试日的集热屋面集热效率、太阳能保证率、耗电量、室内温度、室外温湿度、噪声、蓄热层表面温度进行计算与实测。将4个测试日作为样本数据,测算北京典型年供暖期的平均日电费。研究发现:各测试日的集热屋面集热效率分别为19.90%、26.34%、25.26%、25.79%,太阳能保证率分别为12.89%、54.04%、30.42%、42.04%。测试日集热屋面日总太阳曝辐照度越高,太阳能空气供暖系统的耗电量越低。各测试日室内温度均在15℃以上,满足设计要求。测试区域的蓄热层表面平均温度为22.7℃,具有一定的辐射供暖效果。测试期间用户对噪声情况的评价为可接受的噪声水平等级。太阳能空气供暖系统的造价为2.7×10~4元,其中施工费约占27%,其余为材料费。根据4个测试日的集热屋面日总太阳曝辐照度,将北京市典型年供暖期的日总太阳曝辐照度划分为4个区间,根据各区间对应的测试日电费及时间,采用加权平均的方法对北京市典型年供暖期的平均日电费进行测算。北京市典型年供暖期的平均日电费为18.53元,折合单位建筑面积为30.05元/m^2。

A solar air heating system with integrated roof collectors for single-storey residential buildings in Beijing villages and towns( covered area is 74 m^2) is designed and built.The main device,system flow and operation mode of the solar air heating system are introduced,and the practices of the collector roof and the ground concrete heat storage layer( hereinafter referred to as heat storage layer) are described in detail.Under the automatic control mode( all-day heating),the test days are 14 to 15,20 to 21,27 to 28 and 30 to 31 December 2017( defined as the test days 1 to4,the test time is from 8:00 on the day to 8:00 on the next day),the heat collecting efficiency of the collector roof,solar fraction,power consumption,indoor temperature,outdoor temperature and humidity,noise,heat storage layer surface temperature on each test day are calculated and measured.The average daily electricity charge in Beijing typical annual heating period is measured by taking 4 test days as sample data.The study found that the heat collection efficiencies of the collector roof on each test day are 19.90%,26.34%,25.26% and 5.79%,and the solar fractions are 12.89%,54.04%,30.42% and 42.04%,respectively.The higher the daily total solar exposure irradiance of the collector roof,the lower the power consumption of the solar air heating system.The indoor temperature is above 15 ℃ on each test day to meet the design requirements.The average heat storage layer surface temperature in the test area is 22.7℃,which has a certain radiant heating effect.The user evaluation of the noise during the test is an acceptable level of noise.The cost of the solar air heating system is 2.7 × 10~4 yuan,of which the construction cost accounts for about 27%,and the rest is material cost.According to the daily total solar exposure irradiance of the collector roof on 4 test days,the daily total solar exposure irradiance in Beijing typical annual heating period is divided into 4 intervals.According to the test daily electricity charge and time corresponding to each interval,the average daily electricity charge in Beijing typical annual heating period is measured by means of average weighting.The average daily electricity charge in Beijing typical annual heating period is 18.53 yuan,and the equivalent unit covered area is 30.05 yuan/m^2.