Nov 21st 2013
Know How... 70
Fun with Thermocouples and Organizing Your Ripped DVDs
Hosted by Fr. Robert Ballecer, SJ
We're making power with thermocouples and it's time to organize your ripped DVD collection.
Although the show is no longer in production, you can enjoy episodes from the TWiT Archives.
Guests: Iyaz AkhtarWe're making power with thermocouples and it's time to organize your ripped DVD collection.
Making NewsIf you've ever wanted to make a Raspberry Pi computer, but thought it was too hard, there's a new Kickstarter project called "Kano." Its goal is to make the Raspberry Pi as simple as a Lego project. You learn to code games like Snake and Pong to get into coding as well. In other Raspberry Pi news, Mathematica and Wolfram Language will be free for the Raspberry Pi. Those are super-powerful programs -- free is a great deal.
Making Power with FIRE!In episode 65 we explained how the "Seebeck Effect" allows a thermocouple to turn heat into electricity. When two different types of metal are joined (via soldering, welding or clamping) a heat source will cause them to expand at different rates, generating a small electrical current. That same device can be used to move heat from one side of the junction to the other when an electrical field is applied to the thermocouple, using a principle known as the "Peltier Effect." Combine many of these thermocouples into a single unit and you have a TEC or TEG. (Thermo Electric Cooler / Thermo Electric Generator). Both of these devices can take advantage of either the "Seebeck Effect" and the "Peltier Effect" to alternatively heat/cool or generate electricity from a heat source. TEGs differ from TECs in that it can handle much higher temperatures than a TEC before failure.
- TEC (ThermoElectric Cooler) or TEG (ThermoElectric Generator)
- Heat Spreader
- Heat Sink/Heat Removal Device
- Thermal Compound
- Heat Source
Assembling your Power Generation Unit
- Coat the TEC/Heat Sink/Heat Spreader with a THIN coat of thermal compound. This is to ensure efficient and EVEN transfer of heat from the heat spreader into the TEC/TEG, into the heat sink.
- Mount your TEC/TEG between the heat spreader and the heat sink. You want an EVEN mounting, any gaps or uneven mounting will cause heat to build up in on part of the element, causing early failure of the unit.
- Wire your TECs/TEGs in series or parallel. In series (negative to positive) your TECs/TEGs will add their voltage to the total voltage availible. Each TEC/TEG will generate ~1.5 volts and a few hundred ma. In parallel (positive to positive, negative to negative) your TECs/TEGs will increase the amperage availible. - Know your application before wiring!
- Cool the "Cool Side" - The power generating capacity of a TEC/TEG assembly will depend on the "Delta T" - or difference in temperature between the hot side and the cold side. Try to make the cold side as cold as possible to maximize power generation.
- Heat it up!