Evaluating Hybrid Heating Ventilation Air Conditioning Technologies in Residential and Commercial Buildings

Abstract

This thesis investigates the potential of hybrid Heating, Ventilation, and Air Conditioning (HVAC) technologies to improve energy efficiency and indoor thermal comfort in residential and commercial buildings across different climates. Focusing on hot climates, the study evaluates three integrated systems that combine direct expansion (DX) systems with indirect evaporative cooling (IEC), desiccants, or both to determine the most energy-efficient and cost-effective solutions. Through EnergyPlus simulations, the research indicates that these integrated HVAC systems significantly reduce energy consumption and improve thermal comfort compared to conventional systems. For instance, in commercial buildings, integrating DX+IEC+Desiccant systems has emerged as highly effective, reducing energy use by up to 37% in Climate Zone 2B and improving comfort levels by 98% in Climate Zone 1A, compared to traditional systems. Additionally, the study explores the cost-effectiveness of these systems, with the DX+IEC system in Climate Zone 2B showing remarkable payback periods. Sensitivity analysis across different climates further reveals the potential of these integrated systems to drastically reduce energy consumption, with reductions in cooling load reaching up to 85% when using the DX+IEC system in commercial buildings in Denver, CO. Moreover, the research highlights the feasibility of achieving net-zero energy buildings through integrating photovoltaic systems, applicable across all examined integrated system configurations in climate zones 1A and 2B. While the outcomes are promising, the research suggests further exploration of more complex building configurations, integration of real-world experimental data, and expansion of the study to different climates and regions, such as the diverse environments of Saudi Arabia. Finally, this thesis provides valuable insights into sustainable HVAC system design, offering more resilient, sustainable, and cost-effective cooling solutions for buildings in hot climates.