On the tesla turbine

On the Tesla turbine - proceed to the simple steam engine, please.

I know of one commercial tesla pump, and it is very expensive. I know of no commercial Tesla engines. Point is - to do this right - with longevity and proper seals - is advanced technology, and to my knowledge, not yet the realm of 'appropriate technology' engineering. Sure, small toys work as examples, just like the Picoturbine works to power an LED light.

We considered the Tesla turbine seriously, I had materials quotes lined up - and then I found out that a typical implementation is 20% efficient, and the best documented one is 60 at obilaser.com. Old-fashioned steam engines are 80-90% efficient. When I recognized this - and considered limited working fluid in a solar concentrator sytem - I said bye-bye turbine.

I can provide a much longer discussion on the above.