ABSTRACT
The electrical quantities relating to the load of a consumer which are measured in a tariff context are only four in number, namely voltage level, demand, units and Power Factor. Nonetheless the number of different possible tariffs that can be applied to any particular class of consumers is enormous as the following classification shows. It is not exhaustive but does serve to indicate the range of possibilities. As a first step in enunciating principles for making choices within this vast range of possible tariffs, cost differences related to voltage level and to geography may be considered. The reflection of geographical cost differences in tariffs is subject to an extremely important practical limitation. This is the problem of drawing boundary lines between cost zones. The fact that the load is weather sensitive means that the level of the load in any hour involves a random element.
