|
|
 |
Optimum Structure Spacing Case Studies
Following is a comparative cost study ** between wood H-frame structures and steel poles, single-pole steel structures were selected for a 138 KV line between Pearsville and Batesville, Texas by the Medina Valley Electric Company.
Based purely on the most economical options, the wood H-frame structures would have to be placed every 750 feet while the single steel pole structures could be placed every 1,100 feet.
This works out to 7.04 wood structures per mile as compared to 4.8 steel structures per mile. This 32% reduction in the number of structures required is doubled to a 64% reduction in some structure accessories. Since each steel structure has only one shaft instead of two, there also is a 50% reduction in shield wire and considerably less assembly and erection costs.
Without the cost of additional foundations, crossarms, hardware, and insulators, plus less expenses related to rights-of-way (as evidenced by the fact that the estimated rights-of-way costs for the single shaft steel pole were 25% below rights-of-way costs for the wood H-frames), ** steel poles became the economical choice on a total installed cost basis. Additional savings were forecast due to reduced maintenance compared to wooden structures.*
* Entire excerpt was taken from, "The Steel Pole Advantages...Reduced Cost Can be One of Them," brochure produced by the Tapered Steel Transmission Pole Institute.
** For actual cost comparisons used, see: "Weathering Steel Poles Selected for 138-KV Line," by Thomas A. Foreman, P.E., Alexander Utility Engineering, Inc., "Transmission and Distribution Magazine," July 1984. |
|
|
|
