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The U.S. military uses large amounts of fuel during deployments and battlefield operations. Consequently, the U.S. military has a strong need to develop technologies that increase fuel efficiency and minimize fuel requirements all along the logistics trail and in all battlefield operations. There are additional requirements to reduce and minimize the environmental footprint of various military equipment and operations and reduce the need for batteries (nonrechargeable) in battlefield operations. The tri-agency SERDP (Strategic Environmental Research and Development Program) office is sponsoring a challenging, high-payoff project to develop a lightweight, small form-factor, soldier-portable advanced thermoelectric generator (TEG) system prototype to recover and convert waste heat from a variety of deployed equipment (i.e., diesel generators/engines, incinerators, vehicles, and potentially mobile kitchens), with the ultimate purpose of obtaining additional power for soldier battery charging, advanced capacitor charging, and other battlefield power applications. The project seeks to achieve power conversion efficiencies of approximately 10% (double current commercial TE conversion efficiencies) in a system with near 1.6-kW power output for a spectrum of battlefield power applications. The project is taking on the multi-faceted challenges of tailoring LAST (Lead Antimony Silver Telluride) / LASTT (Lead Antimony Silver Tin Telluride) nanocomposite thermoelectric (TE) materials for the proper temperature ranges (300 K -700 K), fabricating these materials with cost-effective hot-pressed and sintered processes while maintaining their TE properties, measuring and characterizing their thermal fatigue and structural properties, developing the proper manufacturing processes for the TE materials and modules, designing and fabricating the necessary microtechnology heat exchangers, and fabricating and testing the final TEG system. The ultimate goal is to provide an opportunity to deploy these TEG systems in a wide variety of current military equipment (i.e., various Tactical Quiet Generator (TQG) systems) and battlefield operations so that they can provide the military with a pathway toward energy savings and environmental footprint management. The paper reviews the progress made on 1) the performance of LAST / LASTT TE materials and tailoring their temperature dependency; 2) evaluating the structural (Elastic modulus, Poisson's ratio and mechanical strength) properties of these materials, 3) developing the necessary LAST/LASTT-based TE modules, 4) developing the required hot-and cold-side microtechnology heat exchangers, and 5) the overall system designs for 30 kW and 60 kW TQG applications and potential performance pathways/differences for these two TQG cases. This work leverages fundamental research sponsored by the Office of Naval Research in developing LAST/LASTT materials.