We pulled the rotor (which contains the field winding for the alternator) and replaced it with a newly fabricated rotor.  A steel shaft was turned to the same dimensions and a pair of HDPE rotor hubs fabricated to duplicate the original dimensions.  Here is a shot of the milling operation using a rotary index table.
Next is a shot of the two completed rotors on their aluminum hubs.  These have not yet been turned completely, and no center holes exist on them.  Later they were completed and used on the new rotor axis pin to complete the replacement rotor. The reasons for replacing the rotor were twofold; first, the old rotor required power to operate, and drew a couple of amps, greatly affecting efficiency.  Second, the old rotor was very massive, containing a great deal of iron and copper.  The new rotor is mostly high density polyethylene and some supermagnets.  The magnets eliminate the need for powering the rotor.

The completed and rebuilt alternator is now an AC generator that requires no voltage to start or operate.  The magnets themselves provide the powerful field needed to create electrical current efficiently.  The new arrangement still produces a three-phase electrical supply that is rectified and then regulated for use.  In our earliest tests, the rotor turned out nearly a volt just spinning it by fingers.  The original alternator required a couple of thousand RPM and a 12 volt supply just to start making any power at all.

Here is a view of the steam turbine (which is powered by a solar heat collector) coupled to the newly rebuilt alternator.  Together, we will now test the pair and see what sort of rotation speeds are necessary to produce useful power.

The completed system works like this.  A solar collector gathers sunlight and focuses it on a heat exchanger filled with water.  The water boils and creates steam which spins the turbine.  The turbine, coupled to the alternator, produces electrical power.  This raw power is then regulated using a switching regulator circuit to produce a high current power source.  This is DC, so a user would have to convert this to AC power to run household appliances.

In the finished system, it will be possible to use a circuit similar to a UPS to convert this power into high grade AC identical to that used by your home appliances.  A grid interface will allow you to put power back into your system and in cases where you are using no electricity, actually run your meter backwards and sell power back to the utility company.  Three such systems like this could completely cool a 2,000 square foot home on hot summer days.  The three turbogenerators would likely be placed in discrete packages that would be placed on the rooftop, tracking the sun and shading part of the sunlight that heats your roof and your home.  Larger units could also be made, but I would like to stress the modular nature of this system and the fact that if one breaks down, the others would continue to power your home.

In an ideal environment, this sort of system would become the norm, with nearly every home creating a good fraction of the power it consumes and returning it to the grid during daylight hours.  Night time rates are typically lower, and cooling then would be cheaper and less demanding as well.  But even in the event that this only cools a home during the summer, it would be a positive step in terms of energy production and environmental issues.  This is essentially a generator system that consumes no fuel except for sunlight.

More details of the system here