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Of the many competing technologies for resource recovery from solid wastes for long duration manned missions such as a lunar or Mars base, incineration technology is one of the most promising and certainly the most well developed in a terrestrial sense. Various factors are involved in the design of an optimum fluidized bed incinerator for inedible biomass. The factors include variability of moisture in the biomass, the ash content, and the amount of fuel nitrogen in the biomass. The crop mixture in the waste will vary; consequently the nature of the waste, the nitrogen content, and the biomass heating values will vary as well. Variation in feed will result in variation in the amount of contaminants such as nitrogen oxides that are produced in the combustion part of the incinerator. The incinerator must be robust enough to handle this variability. Research at NASA Ames Research Center using the fluidized bed incinerator has yielded valuable data on system parameters and variables.

This paper builds on a steady-state investigation of waste heat reuse in an Advanced Life Support System (ALSS) for a Mars mission with a low degree of crop growth. In past studies, such a system has been defined in terms of technology types, hot and cold stream identification and stream energy content. The maximum steady-state potential for power and cooling savings within the system was computed via the Pinch Method. In this paper, the next step is taken toward achieving a pragmatic estimate of costs and savings associated with waste heat reuse in terms of equivalent system mass (ESM). In this paper, the assumption of steady-state flows are discarded, and a proposed schedule is developed for activities that are of interest in terms of waste heat reuse. The advanced life support system for the Mars Dual Lander Transit Vehicle is the system of interest.

Commercial aviation relies almost entirely on subsonic fixed wing aircraft to constantly move people and goods from one place to another across the globe. While air travel is an effective means of transportation providing an unmatched combination of speed and range, future subsonic aircraft must improve substantially to meet efficiency and environmental targets. The NASA Fundamental Aeronautics Subsonic Fixed Wing (SFW) Project addresses the comprehensive challenge of enabling revolutionary energy-efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies, and the development of unconventional aircraft systems, offer the potential to achieve these improvements.

Continuous removal of carbon dioxide is one of the most critical processes in a spacecraft air revitalization system. Recovery of the waste carbon dioxide and its subsequent conversion to oxygen become essential for long-duration human space missions beyond Low-Earth orbit where re-supply of consumables such as oxygen is neither practical nor economical. The current CO2 removal technology employed in the United States Operating Segment (USOS) of the International Space Station (ISS) operates in an open loop mode where the waste CO2 is vented to space. A compressor is required to facilitate CO2 recovery capabilities. The CO2 removal process itself is one of the most energy-intensive processes in the life support system of the ISS due to the water vapor recovery method involved in the process. This paper discusses the design and development of a low-power CO2 removal system that has capabilities to recover and compress the CO2 for recycling oxygen.

The International Space Station's air revitalization system operates in an open loop mode and relies on the re-supply of oxygen and other consumables from earth for the life support of astronauts. A compressor is required to deliver the carbon dioxide from a removal assembly to a reduction unit to recover oxygen and close the oxygen loop. We have developed a temperature-swing adsorption compressor (TSAC) that is energy efficient, quiet, and has no rapidly moving parts for performing these tasks. The TSAC has the capability to remove carbon dioxide (CO2) from a low-pressure source, and subsequently store, compress, and deliver it at a higher pressure as required by a processor. As such, the TSAC is an excellent candidate for interfacing CO2 removal and reduction units in the air revitalization loop of a spacecraft for oxygen recovery. A TSAC that uses air as a cooling medium was developed and tested at NASA Ames Research Center.

The paper analyzes energy use and emissions per GJ of various fuels delivered to the vehicle fuel tank, covering extraction, fuel production, transportation, storage, and distribution phases of the life cycle of alternative fuels. Drawing on a number of existing studies, the modeling issues and approaches, main results and insights are summarized. The range of estimates in various studies is large; however, common patterns can be observed. The analysis indicates, that conventional gasoline fuel cycle has robust advantages with respect to energy efficiency, conventional pollutant emissions, and most importantly, existing infrastructure compared to alternative fuels. Fossil fuel based alternatives like CNG, NG–Methanol, NG–FTL do not result in significant improvement in fuel cycle environmental performance. Biofuels offer the benefits of lower and even negative GHG emissions, sustainability, and domestic fuel production.