Feasibility assessment of adopting distributed solar photovoltaics and phase change materials in multifamily residential buildings

Abstract

• Feasibility study to assess adopting PVs and BioPCMs in multifamily residential designs. • Energy-efficient VRF-HVAC systems are considered in multifamily residential designs. • Simulation-based assessment is conducted with LCCA of multifamily residential designs. • Effects of annual site energy use intensity and availability are investigated and discussed. • 35–50% Of annual energy needs can be satisfied, with lifecycle cost reductions of 6–9%. Given the growing environmental concerns due to climate change, the combination of renewable energy systems and feasible design optimization strategies of buildings, has been considered as a promising integrated solution to promote sustainable residential infrastructure and maintain carbon emission reductions. As part of promoting sustainable residential infrastructure development projects involving low-energy buildings, this study evaluates the feasibility of applying distributed solar photovoltaic (PV) systems and Bio-phase change materials (BioPCMs) with energy-efficient variable refrigerant flow (VRF) systems in multifamily residential buildings. To this end, this study conducts lifecycle cost analysis (LCCA) of low-energy multifamily residential building (LEMRB) design with energy-efficient VRF type systems, distributed solar energy generation systems (PVs), and BioPCMs. To enable LEMRB design, Korean medium-sized multifamily residential buildings on the national level, are selected as a case study. The results demonstrate that the application of both solar PV systems and BioPCMs to medium-sized multifamily residential buildings significantly help to reduce 35.03–49.78% of the total annual energy needs of each medium-sized multifamily residential building in various Korean climatic locations. Accordingly, the lifecycle cost (LCC) of low-energy medium-sized multifamily residential buildings showed significantly feasible in all Korean climate locations, as the discounted payback (DPB) period of investment costs is ranged from 5 to 8 years. However, further systematic studies to optimize the efficiency of solar energy systems and phase change materials are required. These include investigating more residential design alternatives and considering the effects of uncertainty and degradation on LEMRB lifecycle performance for achieving more sustainably and cost-effectively low-energy multifamily residential buildings in the future.