Puget Sound Energy electric transmission and substation project
Bainbridge Island transmission line and substation
Winter 2009-10 project updates
- Puget Sound Energy is planning to hold a community meeting in the early spring 2010 to announce an infrastructure plan to address peak load solutions and transmission system reliability for the Bainbridge Island transmission line and substation project
- In addition to considering infrastructure solutions to address the island’s growing need for electricity, we are currently working with the community to explore conservation solutions to meet all or part of the forecasted needs
- If conservation solutions do not lower usage, construction could begin as early as 2011 on the substation portion of the project
- Correction: at our August 25 public meeting we reported that there have been eight transmission outages in the past six years on our Murden Cove and Winslow substations. The correct number is 10 transmission outages in the past six years, two on our Murden Cove substation and eight on our Winslow substation
Project overview
Our analysis of the electric needs on Bainbridge Island shows that the island requires the addition of a new substation to meet the growing demand for power and a new transmission line to increase reliability. Our two substations – Murden Cove built in 1980 and Winslow built in 1966 – are at maximum capacity. One way to address the capacity problems facing the island is to build a new substation. Increased conservation by island residents may also provide short- or long-term solutions.
Conservation solution
Decreasing electric usage – especially on the coldest winter days when electric usage increases for heating and light – may postpone or eliminate the need to build a substation. Conservation, however, will not address reliability issues. PSE is working with community and civic leaders to develop a plan that outlines the amount of power the community needs to conserve and to provide guidance on how the community can conserve.
Follow the community dialogue on the conservation issue.
Infrastructure solution
To increase reliability and meet current and future energy needs on Bainbridge Island, PSE is proposing to construct a new 25 megavolt (MV) substation and a 115 kV transmission loop between our Murden Cove and Winslow substations. The new substation will serve the needs of the community of Winslow. It will also increase reliability to the island by serving as a back-up to our Winslow and Murden Cove substations.
The new transmission line will also increase reliability because Murden Cove and Winslow substations will be fed by two transmission lines instead of one. If one line goes out, the other line would maintain the flow of power to the substation and customers.
What is a transmission line?
Transmission lines are key elements in the electrical distribution system. The lines safely transport high voltage electricity from power generation sources like dams and wind farms to substations in local communities. Transmission normally takes place at voltages of 55 kV and higher.
What is a substation?
Substations are critical links in the electricity distribution system, containing utility circuit protection, voltage regulation, and equipment that steps down higher voltage to lower voltage. Before reaching homes and businesses, power is routed through our transmission system to a substation where it is changed to a lower voltage that can be utilized by customers.
Committed to keeping you informed
PSE will continue to provide updates to the community. We will notify residents who live near the project area when construction will occur. It is our aim to complete the work with as little disruption as possible.
Download the information
Download these PDF files for more detail on the Bainbridge Island substation and 115 kV electric transmission project.
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