Electric Maintenance Projects
Electric power was first brought to the Estes Valley by FO Stanley in 1909 with the construction of the Fall River Hydroplant, built to provide electricity to his new hotel. Since that time the system has grown to cover around 280 square miles with over 3,000 miles of powerline, including service to Glen Haven to the north and Allenspark to the south, and the customer base has grown from a handful of hotels and residents to well over 10,000 customers. While many of the improvements to the electrical system are made thorugh capital projects, regular system maintenance provides opportunities to upgrade and improve on an ongoing basis.
Here are some of the ways Light & Power is continually improving:
Light & Power's goal is to provide safe and reliable electric service to its customers. The tree trimming program helps the department meet this goal. In order to do so, tree crews execute proper clearing and trimming techniques by placing emphasis on “natural trimming” to laterals (side trim, drop crotch, overhang). The lateral branch trimming technique is a recommended best practice of the International Society of Arboriculture (ISA). Light & Power's tree trimming program operates on a five-year cycle.
The basic trimming criteria are as follows:
Side Trim: Trees growing along the side, into, or toward electric power lines or utility space shall be trimmed.
Trim Drop Crotch: Trees directly under and growing into electric power lines should be removed or trimmed.
Light & Power is currently reviewing the vegetation management policy and will post it on the Vegetation Management page when the review is complete. The tree trimming contract currently held by Adam's Tree Service.
Street Light Upgrades
In 2011, Light & Power began upgrading the high-pressure sodium (HPS) bulbs in the street lights throughout Estes Park to LED bulbs. Light & Power maintains over 500 streetlights in the Estes Valley including highway lights along Highways 34, 36, and 7, neighborhood street lights, and the decorative lights around downtown. Following several initial pushes to change out stretches of lights, upgrades are now being as the HPS lights need to be replaced. In some instances, the new LED bulbs can simply be swapped into the existing light fixture; in other cases, an adaptor must be used to upgrade the light. In some fixtures, the whole light head needs to be replaced, as there is no adaptor.
LED lights consume about 50% less energy than HPS bulbs, and last about 4 times longer. This translates into significant savings in energy costs to the Town in energy savings and maintenance costs over the lifetime of the bulbs. LED lights also increase safety and night-time visibility. The LED lights being installed along the highways and neighborhoods have an improved distribution of light compared to HPS lights. The LEDs shed light along the roadway, increasing visibility in dark spots between street light poles, rather than solely dumping light directly below street light fixtures as the HPS luminaires did. The LEDs also have a shield that can be added to reduce the amount of back-lighting that spills behind the street light pole and onto adjacent properties. LED lights also produce a white light, where HPS lights produce a light that looks yellow/orange. The white light allows colors to appear more natural at night, improving color rendering and visibility of other vehicles, pedestrians, and wildlife.
Fuse and Recloser Upgrades
Light & Power crews are upgrading the fuses at critical junctions throughout the Light & Power service area. TripSaver Cutout-Mounted Reclosers are installed in place of traditional cutout fuses along overhead distribution powerlines (lower photo to the right).
They are often placed at the junction between the main line and lateral lines. TripSavers are an integral component of the system upgrades that Light & Power has added to its service area.
TripSavers can be set to function two ways: as a traditional cutout fuse or as an OCR (oil circuit recloser). When set as a cutout fuse, it senses unusually high current (fault current) and opens. This breaks the circuit and turns off the power beyond that opening.
When the TripSaver is set to function in place of an OCR it can be programmed to "operate" (open and close) a certain number of times before it's locked out (opens and stays open). A TripSaver will lock out under two circumstances 1) high current for longer than a set time (1-1.5 seconds); or 2) current higher than the programmed load limit for any length of time. Otherwise, the TripSaver will operate to allow the fault to clear; this causes the power to blink, but it will stay on. For example, if a tree branch falls on the line and causes a fault, the TripSaver will operate three times; this allows time for the branch to fall off the line and clear the fault. Without the TripSaver, the single fault would cause the cutout fuse to open and power beyond that point would be lost until the fuse could be replaced.
The TripSaver has an additional setting as a safety precaution for working on energized lines. The one-shot setting programs the TripSaver to open immediately once it senses a specified load (amount of current).
TripSavers have the advantage of requiring less maintenance than an OCR since there is no oil to refill. It also maintains a record of operations, so crews have a better idea of what's happening along the line.
For more information or questions regarding any of these projects, please contact Sarah Clark, Administrative Assistant, at 970-577-3627 or firstname.lastname@example.org.