We get an inordinate number of emails from people who have it in their heads that they want to design a steam system for electric power starting with a steam turbine. Rather than trying to educate such people one at a time we hope that this particular article will enlighten them (and you).
Steam turbines work quite well in major power plants, naval warships, and the like. Such applications require huge amounts of horsepower. For anything under 250 hp, you're going to run into problems, which we will address.
1. Small steam turbines are horrendously fuel inefficient. A 3 hp steam turbine will consume ten (10) times the amount of fuel a 3 hp steam engine will to produce the same amount of power. A Tesla turbine is even worse. Nikola Tesla was an electrical genius. What he knew about steam enabled him to build the most inefficient engine known to man.
2. The boilers for steam turbines cost, on the average, three (3) times as much as boilers for piston steam engines. This is due to the effect of microscopic droplets of water in a steam turbine. Such droplets have no effect on piston steam engines. Steam turbines turn at an extremely high rate of speed. Microscopic droplets of water act as grains of sand would in normal machinery. Dust causes the same problem.
3. Steam turbines only act at full efficiency (even the big ones) at full throttle. For example, electric power utility plants don't use one big steam turbine. Instead they use several steam turbines running at full throttle. When the demand for electricity increases, more turbines are brought on line to fill that need. When it lessens, they are disconnected. This set up requires very expensive switching equipment.
In short, don't embarrass yourself by emailing us about your would-be steam turbine project. Order our Special Steam Package, study it, and then we may be able to have an intelligent discussion about what it is you want to accomplish.
This page was updated on 5 November 2011