July 28, 2008

PSE Installs Solar-Powered Anti-Corrosion Systems on Natural Gas Pipeline

Puget Sound Energy has added two new solar-powered systems to those installed since 1984, to help protect the utility's underground natural gas system in the western part of the Washington state of the US.

Puget Sound Energy's (PSE) two newest solar-powered systems in Edmonds, Washington, produce electric current along more than six miles of buried natural gas steel pipe to block corrosion caused by the electrochemical reaction between the metal pipe and the surrounding soil.

The anticorrosion technique, called cathodic protection, uses a small amount of electric current to charge the pipe's surface and direct the rust to an anode. This in effect tricks the pipe, targeting the corrosion elsewhere, increasing the longevity of the pipe and in the long-term, decreasing the potential for natural gas leaks.

In total, the utility's nearly 85 solar-powered cathodic protection systems installed in six counties protect more than 250 miles of buried natural gas steel pipe.

With approximately a quarter of PSE's 300 cathodic protection systems operating on solar power, PSE claims to be the only Washington utility using solar technology to protect its natural gas system, and one of the largest users in the US.

Sue McLain, PSE senior vice president of operations, said: "While good for the environment, these solar installations give us the latitude to operate our natural gas protection systems in remote areas where other sources of power may be difficult to install or operate. Its fitting for PSE, which operates the Pacific Northwest's largest solar power-generating facility at our Wild Horse wind and solar facility near Ellensburg to have also helped pioneer this technique to take advantage of solar energy to help protect our natural gas system."