Tom gave us a very brief presentation on how a sterling engine works and what a Peltier junction is.  He had a few different experiments up and running to show us what each one did and its purpose of doing it.

The sterling engine is a heat engine that was invented in 1816 by Robert Stirling.  He explained how it has more efficient than a car engine, but it is only used for submarines and yachts, because of how quiet the engine is compared to a car engine.  It is a work in progress and is predicted to someday take over as the main engine used in almost everything.  One main difference on why the sterling engine is so different than a gas or diesel engine is that it does not have an exhaust, so no explosions take place which means the engine runs very quiet.  The engine also uses an external heat source which is usually powered by solar energy.  There are many ways to put together a sterling engine but this seems like the most simplistic way.

A Peltier Junction is a thermo-electric cooler and heater.  It consists of two ceramic plates, in which the peltier devides are connected to a DC current and voltage device.  Once connected, one side of the device gets cold while the other gets hot.  The side you need to use depends on what experiment or test you are running.  I am not sure which side Tom Vale used but I believe it is the cold side.  Tom used a fan running on water that was connected to the Peltier device.  The fan was powered because of the current that was going through the device and the water.

Overall, I thought he made a great presentation.  He also showed us an experiment with a bug zapper and a grill lighter.  Even though they were not as interesting as the first two, it was good to see what is possible.  Looking forward to the next lab and the field trip!