Economic benefits of high temperature, synthetically reinforced cellulose insulation for overhead distribution transformers

A high temperature, synthetically reinforced cellulose insulation has recently been introduced. This new insulation has superior thermal endurance compared with existing thermally upgraded kraft papers. Loading of overhead distribution transformers is generally limited by the thermal endurance of cellulose insulating materials. The availability of an insulating material with more thermal durability reduces these limitations by allowing higher continuous operating temperatures, more extreme overload excursions, or a combination of both. In the case of overhead distribution transformers, loading practices could be changed to lower the kVA rating installed to serve a given load. This would have two advantages: lower first cost of the installation and lower no-load losses on the system. This paper examines the economics of such a change in loading practice for an example residential load.