Mountainview Trivia

On the name plate of the generators at the power plant you will notice that it states that the generator is "Hydrogen Cooled." Why Hydrogen instead of air? According to the second edition of NADON and GELMINE'S "INDUSTRIAL ELECTRICITY" there are two types of alternators: One is a Salient Pole type where many projecting field poles are mounted on a cast iron spider. Since the number of poles determine the speed at which the alternator spins, a Salient Pole alternator need not spin at high RPMs. A 24 pole alternator therefore has to spin at 300 RPMS to produce 60Hz. The other type of alternator is a Turbo-Type. A steam turbine has a higher efficiency when operated at high speeds which makes the designing a Salient Pole machine difficult because of the high centrifugal forces. Projecting poles also cause excessive wind losses and make the alternator noisy. To overcome these undesirable features, alternators intended for steam-turbines have their field structures made cylindrical in form and small in diameter, with two or four poles. Because of this streamlining, however, it becomes difficult to cool the alternator. To overcome this problem, hydrogen is used instead of air. Hydrogen being much lighter than air causes 10% less windage loss which also reduces noise. Also, hydrogen is a better heat conductor than air enabling 20% more power to be supplied from a given machine. Another benefit is less oxidation in the windings.
So there it is folks. You would have thought that they would have learned a lesson from the Hindenburg, but here we are mixing a flammable gas and electricity. Go figure!