Low average wind conditions (3 to 6 mph) require a turbine design that has a large swept area.

This turbine design uses 5 blades and is about 6 feet in diameter.

Using a small tail, is intended to help stability in turbulent conditions. The tail square area can easily be increased if the yaw of the turbine is poorly controlled.

High wind conditions could easily over-speed the generator and turbine. A mechanical brake designed to slow the generator by directly applying a friction pad to a small brake rotor on the opposite end shaft. The brake lever is manually actuated by a rope.

The experiment will record wind speeds and generator output using a dummy load. The recording is done with a logging voltmeter and laptop computer.

This weather station is designed to monitor wind speed and direction as well as rainfall. (That sensor is covered temporarily).

The weather station is battery operated and contains a small radio transmitter.

Every 5 minutes, a sample reading from each of the 3 sensors is transmitted to a monitor and display at the base of the hill.

The radio transmitter has a range of 300 feet.

The wind data indicates average wind speed is about 3 mph.

The turbine design is intended for low wind, slow speed operation.

Over-speeding of the turbine must be avoided during high winds.

Conventionally, dummy load circuits are used to brake the generator.

This generator has a manually operated mechanical brake as well.

The friction brake and rotor are not designed for rapid braking of the turbine.

The brake is generally applied gradually.

The brake will work as a holding brake in moderate wind conditions.

Custom boring of brake rotor

This antique lathe is still a good machine tool for this type of work.

The lathe capacity is large and tooling is not intended for such small parts.

The original design of the lathe included large, overhead flat belt pulleys as drivers.

Today, the lathe operates using a variable frequency drive on 1 phase input.

The "rotor" is a small cast pulley from the local farm supply store.

The brake arm is designed to bolt onto threaded holes in the generator.

The friction material is very durable and weatherproof. 

The generator originally operated a printing press in a large factory.

Permanent magnet field.

180 volt dc armature.

Totally enclosed, fan cooled.

1.5hp 

Although not weather protected, several coats of water proof paint help

The generator alone weighs 62 pounds.

The fan and fan cover are removed.

Gasketing and sealant are used on the terminal box. 

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