Cleantech Market Intelligence
Transmission Superhighway Takes Shape
In a previous blog, I focused on the expansion of high-voltage transmission systems driven by utility-scale wind generation in the multistate arc that stretches across the central United States, from the Texas Panhandle to North Dakota. Many of us have underestimated the impact and potential of this resource as a contributor to many states’ renewable portfolio standard targets (RPS). Headlines about new utility-scale solar projects obscure the fact that installed utility-scale wind capacity is at least 5 times that of solar.
Recently, I looked into the long-term electric transmission plans for every region in the United States and found interesting developments in the Southwest Power Pool (SPP) region. SPP covers much of the Great Plains and the Southwest, including all or part of an eight-state area that includes Arkansas, Kansas, Louisiana, Mississippi, Missouri, New Mexico, Oklahoma, and Texas. The geographical footprint of SPP overlaps slightly with other independent system operators (ISOs) and regional transmission organizations (RTOs) such as Midwest Independent System Operator (MISO). SPP’s footprint can be seen in the map below.
SPP Regional Footprint
(Source: Southwest Power Pool)
In 2008, SPP announced that it plans to build the electric equivalent of the U.S. interstate highway system – an interstate transmission superhighway that would serve as the backbone of a higher capacity, more resilient transmission grid, while providing increased access to low-cost generation, improving electric reliability, and meeting future regional electricity needs.
The SPP transmission plans I saw show that this conceptual idea is beginning to come to fruition as new 345 kV transmissions systems are being built and older systems are upgraded. Many of these projects have been completed by the transmission owner/entities in the region to address congestion issues in corridors like the Omaha/Kansas City to the Texas Panhandle route. The figure below shows recent transmission system builds and upgrades.
SPP Regional Transmission System
(Source: Southwest Power Pool)
On the Horizon
Meanwhile, ABB has debuted new, 1,110 kV high-voltage direct current systems. A recent announcement by ABB on new products with 1,110 kV high-voltage direct current capabilities raises the bar again. Until this announcement, 765 kV lines were the largest capacity lines available, and most transmission lines are currently in the 230 kV to 350 kV sizes. ABB and other vendors (such as Alstom Grid, General Electric, and Siemens) are focusing on the Asia Pacific markets in China and India, as well as Northern Europe, where major utility-scale wind projects now under construction will need to be connected with urban areas. ABB’s announcement is exciting because it raises the high-voltage capability to a new level, well above what we currently see here in the United States. I can only imagine that ABB will be talking to SPP about how to take the transmission superhighway to the next level.