Minnesota-based Xcel Energy, operator of utilities in eight states, has replaced the last miles of old cast iron pipe in its natural gas utility infrastructure with the final work in its combination utility in Colorado.
Cast iron pipe, the state-of-art for the industry 60 years ago, has been the source of continual leakage and many gas pipeline failures in recent years and pipeline operators have been working to replace it in their systems (see Daily GPI, Nov. 26, 2012).
Calling it a milestone in modernizing and investing in its 36,120-mile natural gas infrastructure, Xcel said it replaced the last increments of cast iron pipe in its system in Colorado early in October, and the cast iron pipe in Minnesota was replaced two years earlier. Xcel utilities serve 1.9 million gas customers in Minnesota, Colorado, Wisconsin, North Dakota and Michigan. No cast iron pipe was used in the latter three states.
In Colorado, Xcel has 21,689 miles of distribution and 2,118 miles of transmission pipelines; and in Minnesota there are 9,843 miles of distribution and 96 miles of transmission pipelines, a Denver-based spokesperson said.
Removing older cast iron pipe, which has accelerated in recent years nationally, benefits the environment by reducing methane emissions, Xcel officials emphasized in making their cast iron-free announcement (see Daily GPI, Dec. 16, 2013). They estimate Xcel has eliminated the emission of the equivalent of about 30,920 metric tons of carbon dioxide by replacing all cast iron pipe, equal to the savings from stamping out greenhouse gas emissions from 6,500 cars.
Xcel's Cheryl Campbell, vice president for gas engineering and operations, said the company is doing everything to ensure it continues to operate "a safe, reliable natural gas system for the public." She said removing all the cast iron pipe took a lot of cooperation from local government in places where the excavations took place.
Xcel made significant investments in recent years to modernize its natural gas system while gas wholesale prices have been at historically low levels, so the impact on utility customers has been kept moderate, the spokesperson said.