In 1999, Public Service Company of Colorado (PSCo) submitted an application to Summit County for the construction of an electric substation that would serve the greater Silverthorne area. That application was denied due to non-conformance with certain provisions of the county’s Lower Blue Master Plan and certain 1041 permit criteria. Since that time, construction of new businesses and homes has increased the need for electricity. Xcel Energy, of which PSCo is now an operating company, has responded to this increase in demand by constructing a new feeder line from the nearby Dillon Substation. Though this new feeder line has benefited the community with additional capacity, it cannot eliminate the need for a new substation.

Every substation has a “maximum capacity” that depends on its number of transformers, and land constraints. Also, transmission lines feeding the substation have a thermal capacity limit. The capacity of the two existing Dillon and Summit substations cannot be increased any further. By 2013, each substation will utilize its complete capacity to service its primary distribution area. At that time, there will be no excess power to switch between the substations. In the event of a transformer failure, the lines will be down until the physical equipment can be repaired. Construction of a new substation not only increases the availability of electric energy, but more importantly, it provides Xcel Energy critical flexibility in how it moves electricity through the Summit County area.

The proposed Ptarmigan Substation Project consists of: (1) the substation; (2) a 230-kilovolt (kV) transmission line “tap”; (3) an access road; and, initially, (4) two buried distribution feeder lines. The transmission line brings 230kV power to the substation. The substation “steps down” the voltage from 230kV to 25kV for distribution to the community. The feeder lines connect the substation to the existing distribution power grid. The Ptarmigan Substation Project also will be able to handle up to 10 additional feeder lines as demand increases.

The study area Xcel Energy has identified for the new substation originally extended north of Interstate 70 by 4 miles. Following the review of comments voiced by the public and complexities associated with the sites analyzed to date, the study area was extended to 4.5 miles. Current standard technology requires the fenced portion of the substation to be approximately 2.5 acres, and the entire site to be typically no more than approximately 7 acres, including grading and landscaping. The transmission line is proposed to be constructed overhead, and the feeder lines are proposed to be buried. During the past decade, Xcel Energy has sponsored numerous public forums to gather input regarding possible site locations for a new substation. Xcel Energy understands that everyone will not agree upon any single site location. That is simply a fact of life. Another simple fact is that demand has continued to grow, and by 2013 there will not be any excess capacity in the two existing substations.

Approvals for the project may take up to a year. Construction of the project will require at least one construction season. Taken together, the approval process must be started soon in order to have the substation operational by 2013. Xcel Energy is currently considering several site locations to determine which is the most suitable for inclusion in our Ptarmigan Substation application.

On Aug. 12, 2010 Xcel Energy sponsored an open house to hear public comments about the proposed Ptarmigan Substation. About 50 people attended, of which several submitted written comments. In general, the comments, combined with comments from previous public open houses, voiced concerns regarded impacts to views, environmental impacts, flood plain issues, locating the substation near existing development, compliance with the Lower Blue Master Plan, fire safety, effects to the Blue River and locating the substation on National Forest System lands.

Each of these concerns continue to be factored-in to determine a suitable location for the Ptarmigan Substation Project. Once our investigation is complete, we will compile the required information and submit a land use application to the appropriate jurisdiction. At that time, it will be up to the governing bodies to either approve or deny the application.

We encourage the Silverthorne community to support our application for construction of the Ptarmigan Substation so that it will be completed by the fall of 2013, ensuring the continuous reliability of your power needs.

Jerome Davis is Regional Vice President for Xcel Energy.

For information on the project, including the information presented at the Aug. 12, 2010 public open house, see: http://bit.ly/aLZxTY.