High voltage dc line planned to cross Iowa

In several meeting across the state, Clean Line invited property owners to voice concerns and make suggestions regarding proposed line routes.

Although wind development is surging in many states, transmission developments lag. The problem is conventional transmission lines. They are hobbled by a lack of capacity.
Clean Line Energy Partners have several plans to address the issue. One, the Rock Island Clean Line, is a proposal to construct and operate a roughly 500-mile overhead electrical transmission line across Iowa to Illinois. The project represents a potential investment of $1.7 billion to construct the high-voltage direct current (HVDC) transmission line. It also has potential to influence up to $7 billion in new wind-farm construction in the region, along with the creation of up to 500 jobs, not to mention up to 5,000 construction jobs.

“Clean Line Energy Partners was created to meet a need to bring power from where it is readily available to where it is needed in the most efficient way,” says Clean Line Director of Development Hans Detweiler. “Northwest Iowa is on the east end of the nation’s wind resources, so it’s the easiest point to acquire wind power. The Rock Island Clean Line would let us bring that power to where it is needed.”

“With the power transmission grid is operating at capacity, there isn’t a lot of new wind-farm construction underway because there is no capacity to get the power from turbines to consumers,” says Detweiler. He says the Rock Island Clean Line was so named because Clean Line had obtained an option to use the abandoned right-of-way of the defunct Rock Island Railroad, in hopes of using the right-of-ways as the route for transmission lines. But after route studies, it was decided a more direct line would be most economical and efficient to construct and operate, as well as having less of an impact on communities and landowners.

“We’ve maintained all along …that we didn’t want to bring transmission lines through towns or disturb sensitive areas,” said Detweiler.  The company held several open-house meetings to show people the plan and ask for suggestions and comments as far as the best places to run a transmission line. Several corridors are being considered to find a best route.

After determining a final route, the corridor will be narrowed to a right-of-way easement of 150 to 200-ft wide, with landowners retaining full property ownership and rights to use the land for farming and other purposes. A difference for the Rock Island Clean Line is that it is a dc transmission line rather than ac. HVDC generally works more efficiently over long distances. And stray voltage issues don’t occur with dc lines as they do with ac lines. What’s more, a dc transmission line requires about a third the right of way of that of that needed for a conventional ac transmission line.

O’Brien and Cherokee counties are being considered for a 65-acre, $250 million station that will convert the ac current from wind farms into dc for transmission to a similar station in northern Illinois. Studies show that most power on a dc line would come from wind sources located within 50 to 100 miles of a converter station.

Costs for the Clean Line are running about $2 million per mile. The line is expected to generate about 5,000 construction jobs over two or three years, and then, property taxes of $7,000 per mile, every year, coming back to each county. And, that does not include the development and construction of additional wind farms that could move forward once an outlet for their power is available.

The proposed line will deliver about 3,500 MW to points east, an amount equal to that now generated by existing wind turbines in Iowa.  “Wind firms in the state, such as Trinity, that manufacture turbine blades in Newton, Axion in West Branch, and Clipper in Cedar Rapids all support projects like this for the potential it brings to the wind industry.”
After completing its public outreach efforts, the plan goes before the Iowa Utilities Board for approval. “Once we receive that, we would begin site planning and permitting and land acquisition efforts. In 2013, we would anticipate signing agreements with customers for the delivery of the power and be finalizing the land acquisition for the actual right-of-way to build the line. Construction would begin in 2014.”
The Rock Island Clean Line is one of four such projects proposed by Clean Line. Similar projects are being proposed for the Grain Belt Express from Kansas into eastern Missouri, the Plains and Eastern Line from Oklahoma into Arkansas and Tennessee, and the Centennial West Line from New Mexico into Arizona and California. “We want to deliver clean energy to communities and people who need it,” said Detweiler. “We’re hoping to create the new farm-to-market road for the 21st Century.”