Abstract :
Charles E. Waddell (by letter): Dividing heat applications into low-potential quantity and high-potential intensity types is a very expressive way of classifying two general conditions. In high-potential heating problems it has been demonstrated that the cost of electrical energy has little or no bearing on economy. Other factors enter that more than compensate for any discrepancy in calorific value between electricity and fuels; for example, electric glue cookers, laundry irons, and apparatus in printing and embossing plants. The field for this type of heating apparatus is decidedly small as compared with the field for low-potential applications; and it is this latter class that presents diverse conditions and offers fascinating opportunities for specific, solution. Elusive in its nature, difficult to measure, and next to impossible to insulate, heat is in many respects a more subtle and difficult form of energy to control than is electricity. When comparing electric heating with fuels in the realm of domestic heating, the fact must never be lost sight of that by means of electrical measuring instruments the quantity of heat delivered by the electrical apparatus can be accurately determined; whereas in the case of fuel apparatus, while the calorific value of the fuel itself may be known, the efficiency of such apparatus is so variable and uncertain that its economy is largely a matter of conjecture.
