Stirling power generator

[Aerein]

The advantage of a stirling engine over a steam engine is that you can use higher temperatures in your topping cycle without dealing with high pressure steam. I think it would be easier to operate safely in an automated mode for this reason. The disadvantage is that you have to use a much large engine displacement, or many small engines. The engines don't have to be built as heavy however, and it might be just as much fun for a DIY person to build 24 small cylinders and hook them all up rather than one big cylinder.