Net energy analysis of electrical transmission lines

This paper presents an analysis of the energy costs inherent in the construction and operation of a 1000-mile length of 765 KV AC, ± 400 KV DC and ± 600 KV DC transmission lines. Calculations were made for the indirect energy costs associated with materials and construction as well as line losses during operation. Environmental losses were evaluated as energy costs by calculating the photosynthetic production losses and converting these energy losses to equivalent coal or electrical units through appropriate conversion factors. In this way all energy costs could be equally compared. By considering the electricity transmitted as equivalent to a certain amount of coal, and by expressing costs in coal units, yield ratios (energy transmitted per unit of energy cost) were calculated. These turned out to be 9.6 for the 765 KV AC, 8 for the ± 400 KV DC, and 11.9 for the ± 600 KV DC line.