Show stored stared rays of sun used in house heating use of the stored rays of the sun for or house heating is the subject of an extensive research program underway at the massachusetts institute of technology seeking to utilize advantageously the vast energy emitted by the sun and trap the heat for useful purposes of man tech has built an experimental peri mental house designed to capture waste heat and store it in the basement in the basement of the especially designed laboratory house is a large well insulated water storage tank to be used for ironing out the fluctuations in heat collected from a source so variable as the sun the buildings heating system consists of a method of forced air circulation so arranged that the flow of air can be either over the hot tank surface or through the coils of a refrigeration system to be installed later this refrigeration system operating on an absorption principle will utilize sunlight as its heat source prof hoyt hottel of M 1 I T states that although several types of energy collectors or heat traps are to be tried first attention is to be given to a shallow boxlike box like heat collecting device placed in a recess on the roof of the building the bottom of the box is a thin sheet of metal painted black to absorb the utmost amount of solar energy firmly fixed to the under side of the sheet is a series of small thin walled metal tubes which are heated by contact with the sheet and which in turn heat water circulated through them the box has several covers of glass inter spaced with dead air regions through which nearly all the sunlight can pass but back through which little heat can escape the sunlight is cover ted to heat when it strikes the metal sheet beneath the box is a layer of mineral wool to prevent the escape of heat in that direction after the water has been warm warmed ed in the heat collector it passes to the storage tank in the basement depending upon the size of the insulated tank water can be kept hot from a few weeks to a half a 3 year by this method |