Cooling Energy Saving Performance of Exterior Greenery System on Department of Energy Reference Buildings
Open Access
Author:
Yuan, Shaojie
Graduate Program:
Architectural Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 20, 2017
Committee Members:
Donghyun Rim, Thesis Advisor/Co-Advisor James Freihaut, Committee Member David R Riley II, Committee Member
Keywords:
Keywords: exterior greenery system cooling energy saving DOE reference buildings EnergyPlus latent heat Exterior greenery system Cooling energy saving Energyplus Latent heat
Abstract:
Exterior greenery system such as green roof and green wall can provide energy and environmental benefits to buildings. The objective of this paper is to quantify cooling energy savings by exterior greenery system on the building envelope. Three Department of Energy (DOE) reference buildings - medium office, hospital, and primary school - are simulated using a building energy modeling tool, EnergyPlus. Cooling energy consumption is estimated for six different exterior greenery system types, three built years and four climates. Heat transfer analysis is performed for both the original roof and green roof layers. Results show that energy saving by the greenery system is more significant in buildings with poorly insulated enclosure and buildings located in hot and dry climates. The results also suggest that latent heat transfer dominates the roof heat transfer process. Cooling energy saving is marginal in building with high internal load such as hospital. However, annual cooling energy saving by exterior greenery system can reach up to 20% for primary school, a single floor building in Phoenix.