The technology under development is a patent-pending thermionic energy convertor (TEC). The concept is inspired by a cesium plasma diode technology, previously developed in the 1960s for space nuclear power but terminated along with the fizzling space initiative in the late 1970s. The company aims to complete curtailed efforts in taking the TEC from laboratory success to a commercialized product.
A traditional TEC heats a refractory metal (e.g. tungsten), called the emitter, to temperatures at which the metal evaporates its own electrons. These "hot" evaporated electrons are conducted across a small gap (<0.020 in) through a weakly ionized cesium vapor, then condense on a "cold" collector (e.g. steel, molybdenum). If the emitter and collector are connected across an electrical load, the electrodes may drive a circuit, thus producing electricity from the heat source. This process is analogous to the Rankine Cycle, where the electrons, themselves, are the working fluid in a TEC and need no turbomachinery to transduce their energy as conventional steam Rankine Cycle power systems do.
TECs are inherently more efficient direct energy converting devices than thermoelectric based devices due to their higher operating temperature differential (>1200 ºF), and thus, higher efficiency (>10%) and power density (10W/cm^2). Of equal importance is a TEC's high operating temperature (>1800 ºF), allowing them to take high grade waste heat directly, whereas current state of the art in direct energy conversion technology, thermoelectrics, must downgrade high temperature heat to operate, lowering their overall efficiency to less than 1% at 1 W/cm^2. Offering an even more compact way to convert heat into electricity, TEC based products lend themselves to easy deployment, integration, and maintenance.
Atlas Energy Systems is leveraging techniques in Cs vapor additives and advanced grooved emitter fabrication to achieve optimal converter performance at a range of temperatures not seen in previous devices. The company plans to use newly available advanced manufacturing techniques for mass production of a grooved emitter and self managing cesium-oxygen reservoir system to accomplish this. Bringing this new capability to the technology is the necessary step in taking TECs from a laboratory technology to a commercialized product.