I m not an engineer but i think the regular slow speed on an electric ceiling fan would be fine.
Gravity powered ceiling fan.
Could use a low voltage switch to limit the power used when inverter isn t needed.
The power was only out for 3 hours but there are stories about this area loosing power for 9 days.
These ventilators provide natural ventilation and are used for intake and relief applications.
Wouldn t it be great to be able to use those and build fans for ourselves and friends family to save money and not have to depend on the electric company.
In any case as you well know the ceiling about the propane heater is very warm while the floors are freezing.
Self powered the gravity light uses gravity to create clean energy includes 2 led lamps with lamp brightness of up to 15 lumens hang in any non electrified space for instant lighting country of origin.
Later men developed belt driven fans powered by waterwheels and later on a simple weighted device where through a series of weights and pulleys the machine moved the fan.
Strong weathertight hoods on these gravity exhaust and supply ventilators feature interlocking arched galvanized steel panels and include a preassembled bird screen.
In this drawing you see that the machine is rocking a canvas fan blade back and forth.
Gravity ventilation gravity ventilators are used to equalize a building s positive or negative pressure created by other fans in the system.
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Air vent 1 500 cfm black galvanized steel electric power roof vent.
Personally i m all for a 12 volt earth battery charging up an old car battery that powers an old treadmill motor that runs a belt to the fan.
When faced with the potential of 40 degrees the thought of having no power is a nightmare.
Inspired by the values of democratic design and do it yourself culture the core idea of the project is to share a simple mechanic recipe to tap into gravity in order to power objects.
As a starting point the machines are mechanical fans exhibiting an accessible tangible and contemplative way to produce energy.
Most of the parts could be re purposed things that others throw away.