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Applied research and technology development (R&TD) is often characterized by uncertainty, risk, and significant delays before tangible returns are obtained. Given the increased awareness of limitations in resources, effective R&TD today needs a method for up-front assessment of competing technologies to help guide technology investment decisions. Such an assessment approach must account for uncertainties in system performance parameters, mission requirements and architectures, and internal and external events influencing a development program. The methodology known as decision analysis has the potential to address these issues. It was evaluated by performing a case study assessment of alternative carbon dioxide removal technologies for NASA's proposed First Lunar Outpost program. An approach was developed that accounts for the uncertainties in each technology's cost and performance parameters as well as programmatic uncertainties such as mission architecture.

Several studies performed in support of the Space Exploration Initiative have identified the need for development or improvement of new or existing regenerative life support process technologies. In part, the need to develop such technologies is dependent on the quantities of consumables that are required by the mission and hence on mission design. Trade studies will be needed to determine appropriate life support system designs that provide consumables to the crew and support systems and dispose of waste materials that are generated. These studies will require quantitative estimates of consumables and waste stream disposal requirements that support a given mission scenario. The NASA Exploration Programs Office (ExPO) is attempting to define the details and logistics of a design reference mission for the first human return to the Moon. The mission is referred to as the First Lunar Outpost.

A preliminary design of a Life Support System (LSS) has been developed as part of an ongoing comprehensive trade study of advanced processor technologies and system architectures for an Initial Lunar Outpost. The design is based on a mission scenario requiring intermittent occupation of a lunar surface habitat by a crew of four. It incorporates physiochemical process technologies that were considered for Space Station Freedom. A system-level simulation model of the design was developed to obtain steady-state material balances for each LSS processor. The mass flow rate predictions were used to obtain estimates of the LSS mass, volume, and power consumption by means of processor sizing correlations that were extrapolated from Space Station Freedom processor designs.

This paper compares scaleup correlations developed at the Jet Propulsion Laboratory (JPL) and at the Langley Research Center (LaRC) for various life support hardware to estimate mass, volume, and power consumption values as a function of feed or product mass flow rates. The scaleup correlations are provided for a few selected advanced life support technologies developed for the Space Station Freedom (SSF). In addition, correlation validity limits and sources of data on various life support hardware are also discussed.