I think a small steam turbine would be a better choice for the first generation cold fusion devices. Such as:
http://www.greenturbine.eu/en/product.php Later, perhaps much later, thermoelectric devices will be the best choice. Stirling engine technology never seems to mature. NASA was developing a space plutonium generator with Stirling engines. They went from using thermolectric chips to a Stirling engine with moving parts. It seems retrograde. Wikipedia says the project has been cancelled: http://en.wikipedia.org/wiki/Advanced_Stirling_Radioisotope_Generator "The development was cancelled in 2013 after the cost had risen to over 260 million US dollars, 110 million more than originally expected." - Jed
