X-Message-Number: 2003 Date: Sun, 21 Mar 93 18:50:20 CST From: Brian Wowk <> Subject: CRYONICS Peltier Effect I have thought of a more efficient passive temperature control system than a heating element in the dewar. The problem with the heating element idea is that no cooling benefit is derived from the LN2 heat of vaporization. Instead of a heating element, why not put a thermopile (collection of thermocouples) in the dewar connected to another thermopile on the room ceiling. By controlling the electric current flowing between the two thermopiles, you can control how much heat is pumped from the ceiling into the dewar. This also is a purely passive electronic temperature control system with no moving parts to fail. --- Brian Wowk Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=2003