UTILISING, WASTE HEAT

Evening Star, Issue 17394, 2 July 1920, Page 7

UTILISING, WASTE HEAT

Many designs have been projected for recovering some part at least of tie waste heat of i>he exhaust. The first attempt is to follow steam practice, and use the pressure of the exhaust g-as to work a gas turbine or'some such form of engine. The second avenue for advance has been to use tie heat of the waste gases to generate 9i«am: which, ■ in turn, is used on some form of engine. The third line of research, which at present se being followed by an English inventor, is to use the waste neat to generate eleobicalpower directly by means of a thermopile. This device is based on the simple fact that if two different metals be jointed together, and the junction heated, a voltage is at once set up. A new kind of thermopile is used, consisting of alternate plates of iron and nickel alloy. The exact oompositaou of this alloy cannot be divulged at present, but it is reasonably cheap, and its electrical resistance is only a little greater than that of iron. It is not sugfested at present that enough power could e obtained to charge a lighting battery, although the inventor has every hope of attaining this after further experiment; but tiere is no doubt that the invention, even in it« present state, is quite caw •£ buss efaciaafcls need far knittoß.