Abstract
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
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
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
Would you like to contribute lesson suggestions? Contact us.
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