Sempra Utilities/SDG&E - Galvanized Towers That Blend Into the Terrain

Palm Desert, CA, August 21, 2012 --(PR.com)-- In order to keep up with the ever increasing demand for energy in the San Diego region, San Diego Gas & Electric (SDG&E) constructed the Sunrise Powerlink Transmission Project. This new 500kV transmission line is essential since no new transmission lines linking San Diego to the energy grid have been constructed in more than twenty-five years. The Sunrise Powerlink is a 117 mile, 500-kilovolt transmission line designed to carry renewable energy from the Imperial Valley to San Diego. The new line will have the capacity to carry up to 1,000 megawatts of clean power (enough energy for approximately 650,000 homes). The project spans a large and diverse area, and affects many people and vast areas of open space, so care was taken to assure successful construction of the Sunrise Powerlink while minimizing visual and environmental impacts. Agencies such as the U.S. Forest Service, the U.S. Bureau of Land Management and the California Public Utilities Commission worked in partnership with SDG&E to ensure the environment was protected from harm and the beauty of the landscape was maintained to the highest degree possible.

For a section of the project that traverses the Cleveland National Forest, it was requested that the lattice towers be colored so that they better blend with the surrounding landscape. SDG&E looked into a variety of options to achieve the desired results, eventually choosing to use a product called Natina Steel that is manufactured in Thermal, CA. A key feature that made this product a good choice is that it is environmentally safe containing oxidizers found naturally in most soils and soft, buffered organic acids (similar to lemon juice). A second key was the unique mottled appearance the product is able to create on the tower steel, which results in a camouflage-like affect.

Natina Steel was applied to the tower steel over 12 working days and the color development occurred over the following 2 weeks (reaction time is determined by sunlight and heat intensity). Natina Steel reacts with the zinc in the galvanized layer to create a rustic brown finish without compromising the protection of the galvanized layer. Also, since Natina Steel contains no pigments but instead derives its color through the oxidation process the color should never fade from sun exposure like typical pigment based colorants (i.e. paints, stains, powder coating, etc.) which fade in a few years as U.V. rays break down the color pigments.

The longevity of this product combined with the fact that it typically costs far less than traditional colorants has fueled Natina Steel’s rapid success since its introduction in the spring of 2010. Natina Steel has already been approved by a number of agencies and has been used to “stain” a variety of metal surfaces including: guardrails, chain-link fences, power poles, lattice towers, stop lights, sign posts, wire mesh, gabion baskets, culverts, mile markers, corrugated metal, isolation casings, grates, trash racks, gates and fences.

For the SDG&E transmission towers, after application and color development was complete, the tower sections were transported via helicopter to their final destinations in the picturesque Cleveland National Forest. The feedback from most observers is that the appearance of these towers and the way they blend with the vegetation exceeded all of their expectations related to what could be achieved with the coloring of galvanized steel...