Study of Costs for a 1 KWe Sodium Heat Engine/AMTEC System

The Sodium Heat Engine (SHE) or Alkali Metal Thermoelectric Converter (AMTEC) is a static thermoelectric energy conversion device that operates at conversion efficiencies that have achieved 19 % and are expected to reach 25-30%. The details of the SHE operating cycle and reports on operation of a variety of cell types and sizes have been described in the literature. [1][2][3] SHE systems have now been built and tested at electric power output levels from one watt to over 500 watts [4]. We have performed a study yielding estimates for volume production costs for a 1 kWe SHE system design. The results are pertinent for both capital cost and delivered electric power cost based on a 1 kWe SHE design closely related to an experimental system we have built and tested. The details of the analysis and the methods employed to characterize the costs of individual cell components, their assembly into complete systems and fuel costs are reported. The costs of the sodium beta”-alumina solid electrolyte (BASE) and labor are treated as parameters in the analysis. The assumptions made for component choices and their manufacturing methods are outlined to allow for an independent assessment of the sensitivity of the analysis to changes in the assumptions which may be required for alternate cell and system designs.