A POWER FROM THE SEA.

Dominion, Volume 7, Issue 1650, 6 January 1914, Page 7

A POWER FROM THE SEA.

SOME POSSIBILITIES. \ Tides, fuel, wind, rain, and food were the headings under which Kelvin somo thirty years ago grouped the sources of power available to man. Many ingenious, minds have pondered over tho problems of stored-up' wave-power, windpower, and solar heat-power, but we do not remember having hoard until now that it has occurred to anyone to utilise as a source of power tho difference of -temperature between the surface and sub-surface waters of tho ocean. ■

This possibility has, howevor, at last been discussed seriously by a writer in the ''Engineering . News." .Tlio mean surface temperature- in tropical seas varies from SO degrees to S5 degrees Fahrenheit. At :\ depth of 300 fathoms this drops to about 40 degrees, and to about 32 degrees on the ocean floor. Here, then, is a difference of temperature so considerable as to represent an indefinitely large •etarclrousm dfcfjjote'fr t'ial energy. ■■■ ■ •■■ •'■. : ■■■ .; ■•" ;•■■;'*''■': '■■ It would bo inexhaustible, and--Bon Campbell, tho. writer in question, suggests that by -means of a heat'engine working' on thp Carnot cycle, and using a convenient and "appropriate volatile fluid, it might be converted into power.' '.'The warm surfaco water constituting the source of heat would ovaporate the fluid under pressure, and' after the vapour had done external work by expanding'iu a nozzle or cylinder, the cold sub-surface water' would eondenso tho vapour to'a liquid ready to use over again." Tlioro is nothing new . under tho sun, and, as Mr. Campbell, says, it is almost incredible that tho gorni of the idea cannot havo occurred to someone- or other in the past, and may perhaps havo been dismissed owing to tho small range of tho temperatures in question, and tho difficulty of bringing tho cold, water to. tho surface." '

Hβ' would place his ideal works in somo of tho coral islands, for deep water may thero be found so close to land that tho power plant might bo stationed on shore. For a floating powprhpuse, such as would in most cases bo required, he would require a flumo, or conduit, 12 feet in diameter, made of wood, with metal bands or nails of such a , weight as to be supported entirely by tho water, and capable of being extended to' any deptli. For driving tho turbine he suggests carbonic acid as it is relatively cheap, non-corrosive, non-explosive, and capablo of giving a high moan effective pressure. In his system he claims that thero would bo no firing of boilers, no incrustation or scale troubles, no vncuum pump, small depreciation, and no rates and taxes. It would in particular suit such industries as the manufacture of calcium carbide, tho fixation of nitrogen, and the liquefaction of air for power and refrigeration purposes.