Vapor-selective active membrane energy exchanger with mechanical ventilation and indoor air recirculation

Andrew J. Fix, Bryan C. Pamintuan, James E. Braun and David M. Warsinger

Applied Energy, 2022, vol. 312, issue C, No S0306261922002197

Abstract: It is widely known that increasing outdoor air ventilation rates in buildings can help improve indoor air quality and mitigate the spread of diseases. However, cooling and dehumidifying outdoor air requires significantly more energy than treating indoor recirculated air. Recent developments in water vapor-selective membranes, which use a vapor partial pressure gradient to remove water vapor from air, offer a unique opportunity to provide highly efficient dehumidification in HVAC systems that can justify high outdoor air ventilation rates without drastic increases in energy consumption. This work presents an analysis of a novel membrane HVAC system referred to as the Active Membrane Energy Exchanger (AMX), which couples a refrigeration cycle with selective membranes to simultaneously cool and dehumidify air. While past selective membrane dehumidification systems have been isothermal, the AMX is the first to deliberately target non-isothermal operation by combining membrane dehumidification and active heat exchange. A thermodynamic model is developed for the AMX in a system that uses both outdoor air ventilation and indoor air recirculation (AMX-R) to elucidate the limitations around increasing ventilation rates. This study is among the first to consider recirculation for selective membrane processes, rather than only 100% outdoor air. The AMX-R can achieve up to 50% cooling and dehumidification electricity savings in warm and humid climates under current ventilation standards. Furthermore, ventilation rates can be nearly tripled with the AMX-R while consuming similar amounts of energy as conventional HVAC systems. Lastly, the incorporation of EnergyPlus building simulations for 114 US cities shows that the AMX-R has the greatest potential in the southern regions of the US.

Keywords: Membrane; Dehumidification; Recirculation; Exchanger; Indoor air (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (4)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261922002197
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:312:y:2022:i:c:s0306261922002197

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2022.118768

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().