TABLE OF CONTENTS - The Professional Green Building Council

Theme B: Creating a livable, healthy and environmentally viable citiesIn this context, anyone such as ventilation system engineer, architect, buildingowner, occupant can be the DM. A DM looking for a system with the lowest initialinvestment cost can select from Designs 1 and 2. Design 1 is a hybrid ventilationwith air supply diffuser installed in the dining room (60 CMH, constant airflowrate fan), and Design 2 is with a 120(CMH) constant fan. Be noted that althoughDesigns 1 and 2 have different airflow rates, they have same initial investmentcosts because their exteriors are identical, and only the internal motor and circuitboard are different, which do not affect the initial costs. A DM looking for asystem with the lowest operation costs can select Design 1. A DM interested in thelowest PD may select Design 18, which is a combination of the hybrid and totalheat exchanger (a hybrid supply diffuser installed in the living room and the diningroom, 60(CMH) ventilation fan in the dining room, and 200 and 250(CMH) totalheat exchangers in the living room and the bedroom, respectively). If the initial oroperation costs of Design 18 are deemed excessive, the DM can select from otheralternatives in Table 3. It should be noted that all designs in Table 3 are nondominatedPareto optimal solutions. This means that no matter which solution isselected, there is no other solution that dominates it. The case for selecting asystem with the lowest CO 2 concentration is not presented here because it isidentical to that of selecting the lowest PD.5. CONCLUSIONS AND FUTURE WORKIn this study, it is shown that optimal design of residential ventilation system inapartment buildings can be found using the genetic algorithm and Paretooptimality. The NSGA-Ⅱ method proposed in [14] was used to improve thediversity of optimal solutions. The objective function includes four elements(initial investment cost, operation cost, PD, and CO 2 concentration). As a result,the DM can choose a optimal solution among the Pareto set according to his/herpreference. The future work includes:408