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DOE OSTI · 1618165

Increasing Compressed Gas Energy Storage Density Using CO2–N2 Gas Mixture

Abuheiba, Ahmad (ORCID:0000000153356180)·Ally, Moonis R. (ORCID:0000000289661950)·Smith, Brennan·Momen, Ayyoub
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Abstract

This paper demonstrates a new method by which the energy storage density of compressed air systems is increased by 56.8% by changing the composition of the compressed gas to include a condensable component. A higher storage density of 7.33 MJ/m3 is possible using a mixture of 88% CO2 and 12% N2 compared to 4.67 MJ/m3 using pure N2. This ratio of gases representing an optimum mixture was determined through computer simulations that considered a variety of different proportions from pure CO2 to pure N2. The computer simulations are based on a thermodynamic equilibrium model that predicts the mixture composition as a function of volume and pressure under progressive compression to ultimately identify the optimal mixture composition (88% CO2 + 12% N2). The model and simulations predict that the optimal gas mixture attains a higher energy storage density than using either of the pure gases.

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Abuheiba, Ahmad (ORCID:0000000153356180), Ally, Moonis R. (ORCID:0000000289661950), Smith, Brennan, Momen, Ayyoub. 2020-05-12. Increasing Compressed Gas Energy Storage Density Using CO2–N2 Gas Mixture. https://doi.org/10.3390/en13102431

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