Exercise 3

Page 1

BEM01 – Solar Gains - 10/04/17 EXE 03 PART I – Latent Loads 1. During our previous analysis, we haven’t considered latent loads due to people and natural ventilation+infiltrations. Re-perform “EXE 02 – Part II – question 3” for both the weather conditions assuming a relative humi dity control between 40 and 60%, during office profile hours. Then, Evaluate the monthly energy needs for cooling and heating both s ensible and latent. Present the results in a table and comment the m. Are sensible and latent loads comparable in terms of energy? Repeat the analysis for the weather conditions assigned to your group. EXE 03 PART II – Solar Gains Use the geometric model developed in “EXE 02 part II - question 4” as the reference case and repeat the following analysis for the two weather conditions assigned to your group. Choose the case with the most reasonable insulation thickness among the alternatives that you have evaluated. Explain the reason of your choice. Consider a standard office profile 8h00 – 18h00 5days/week for heating, cooling, people presence and internal gains. Consider a ventilation rate of 1. 0 during working days and 0.2 duirng night and weekend days. 1. The first objective is to understand the role of energy gains, starting with solar gains through transparent surfaces. How much energy does windows gain? Extract the hourly solar gain (in kWh) and calculate, with excel, the monthly daily average (kWh/day). Repeat the calculations for four different orientation of the windows (South, North,East and West) and plot daily average solar gains in months, in a graph, for the 4 orientations of the windows. Then, check the value of internal gains and calculate the daily average (it should be constant) and compare it with the solar gains in the same graph. 2. You want…