Calculating the Mass Flow Rate of Condensate Produced in an HVAC system, in Connection with Independent Variables. How People Can Use Water Sustainably

This study investigates how condensate water produced by HVAC systems can be quantified, modeled, and repurposed to promote sustainable water use. The research develops a regression-based framework linking the mass flow rate of condensate to key independent variables — including dry bulb temperature, relative humidity, tonnage of the HVAC unit, and fan speed. By constructing and modifying existing mathematical models, the paper aims to establish a predictive equation capable of estimating the condensate yield from air-conditioning units under varying environmental conditions. The author situates this analysis within the larger context of global water scarcity and the need to reduce reliance on energy-intensive desalination plants, demonstrating that the water generated as a byproduct of HVAC operations could serve as a decentralized and renewable water source.

Methodologically, the paper combines thermodynamic modeling, psychrometric analysis, and data from established HVAC studies to derive quantitative relationships between the system’s parameters and condensate output. Using Changjiajin’s mathematical model as a base, the research adapts it to incorporate fan speed and air mass density as dynamic variables, allowing for real-time prediction of condensate production. Through literature review and comparative analysis, the study also assesses the feasibility of condensate collection across climate zones, particularly emphasizing humid, high-temperature regions such as the Middle East and Southeast Asia. In applying theoretical models to real-world examples, the author highlights potential savings in energy and costs—for instance, commercial facilities like the Dubai Marina Mall could recover hundreds of thousands of gallons annually, translating into significant reductions in water expenses and carbon emissions.

The findings underscore that condensate recovery from HVAC systems represents an underutilized but powerful tool for sustainable water management. By integrating predictive modeling with environmental policy, the research demonstrates how simple modifications—such as condensate collection tanks and filtration systems—can transform air conditioning infrastructure into efficient water recovery networks. Beyond technical innovation, the paper calls for stronger governmental and corporate mandates to incentivize condensate reuse, framing it as both an ecological and economic necessity. In doing so, the study bridges engineering precision with environmental policy advocacy, contributing to broader goals of sustainability, climate resilience, and urban water self-sufficiency.