Equivalent System Mass Comparison of ECLSS CO 2 Removal Technologies

Madeleine Oliver; Lawrence Barrett; Kevin Lange; Thomas Chen; Imelda Stambaugh

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NASA NTRS · 20260005251

Equivalent System Mass Comparison of ECLSS CO 2 Removal Technologies

Madeleine Oliver·Lawrence Barrett·Kevin Lange·Thomas Chen·Imelda Stambaugh

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Abstract

This project employs equivalent system mass (ESM) analyses to evaluate and compare state-of-the-art spacecraft CO 2 removal systems. The ESM methodology converts sizing characteristics such as volume, power, and cooling requirements into a unified metric of mass, allowing for simple quantitative comparison of equipment impacts on a system level. Comparison of six high TRL technologies – the Carbon Dioxide Removal System (CDRS), Thermal Amine Scrubber (TAS), Carbon Dioxide Removal Assembly (CDRA), Four-Bed CO 2 Scrubber (4BCO2), CO 2 and Humidity Control Swing Bed (CHC), and the Carbon Dioxide Removal by Ionic Liquid Sorbent (CDRILS) – was achieved using an existing ESM spreadsheet tool that formerly ranked such technologies for consideration on Gateway. Fidelity of the tool was increased through revision with the most up-to-date sizing and performance data for each technology. ESM values were then estimated using NASA-supplied Lunar, Martian, and low-Earth orbit habitat infrastructure costs. This paper details the ESM approach used, lists major performance variables for each CO 2 removal option, and summarizes conclusions of the technology comparison. The results are intended to act as a guide to assist programs in their selection of CO 2 technologies best suited for a specific vehicle or mission.

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Madeleine Oliver, Lawrence Barrett, Kevin Lange, Thomas Chen, Imelda Stambaugh. 2026-07-12. Equivalent System Mass Comparison of ECLSS CO 2 Removal Technologies. https://ntrs.nasa.gov/citations/20260005251

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