Old-time mechanical workings used regulators. Ever take apart an old crank-up 78 RPM Victrola? I have. While most wind-up devices go fast as the spring is tight, and slow down as it unwinds, the Victrola had centrifugal weights that spread out as the mechanism speeded up, and this caused the platter to settle in at a constant speed. There was a screwdriver adjustment to fine tune the speed if Caruso didn't sound quite right.
I don't remember if it worked by pure pendulum effect, or if it applied pressure to a felt braking mechanism. Either way, the end result was a constant speed for a long time instead of a quick spin and fizzle. I've seen the same type of regulator in the machine room above an ancient Otis elevator as part of the electro-mechanical controls. Adding a regulator like this would give a longer, steadier run to a fan.
As far as tours, The Northeast Sustainable Energy Association arranges open houses at various private residences, businesses, schools, and non-profits in New England, New York, and New Jersey on the first weekend in October. You can look at http://www.nesea.org/greenbuildings/
as the time approaches to find places to visit.
Be warned, the term "Green" is so overly broad as to be meaningless. The tours range from builders showing off new McMansions with expensive EnergyStar appliances, to standard houses with a few panels added, to self-designed off-grid homesteads. A memorable homestead built in the mountains had with south-facing windows, a wood stove, and 500 watts of PV for lights, refrigeration, water pump, stereo and a clotheswasher. If you live in the Northeast, pick through the listings to find the features you are interested in. I've been to over a half-dozen of these, and some of the stuff is pretty cool.