Thermal Generator

Abstract

Sterling engine with a generator
Sterling engine with a generator

Electricity generation with a Stirling engine.

Portable

Yes

Principles Illustrated

The Stirling engine spins a generator to light an LED. Thermal generation of electricity.

NCEA & Science Curriculum

PHYS 1.2, PHYS 2.6

Instructions

The generator is a motor with cork,  LED, current-limiting resistor
The generator is a motor with cork,
LED, current-limiting resistor

Place a fuel pellet under the engine and ignite it. Takes a couple of minutes to heat up, spin with finger to get it going. After the engine is spinning well, spin the generator by gently pressing the cork against the engine’s wheel. Note that the LED will only pass a current in one direction so flip the motor if nothing happens. The engine will need to be running at a good speed to light the bulb.

Safety

Watch the flames. The engine needs to be mounted otherwise it jumps around too much and can fall off a table top. Individual teachers are responsible for safety in their own classes.

Individual teachers are responsible for safety in their own classes. Even familiar demonstrations should be practised and safety-checked by individual teachers before they are used in a classroom.

Related Resources

  • Wind Generators
  • Hydroelectric Generators
  • Bicycle Generator

Notes

Note that generators can be very efficient (95%) but a thermal engine that spins them cannot be better than a Carnot engine with efficiency

Carnot

Thermal power plants often run at more like 40% or less efficiency.

Sometimes the “waste” heat can be used for other purposes.

References

Stirling Engines: http://en.wikipedia.org/wiki/Stirling_engine

Genesis Energy Generation Sites

Teaching Resources

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Credits

This teaching resource was developed with support from

The MacDiarmid Institute
Faculty of Science, Victoria University of Wellington
School of Chemical and Physical Sciences, Victoria University of Wellington

Copyright

Copyright and fair use statement