Green Manufacturer - November/December 2011

Rock Island Clean Line Schedule
January 2010
Kickoff

2010-2013
Public Outreach, Regulatory Approval,
Siting Permitting, and Begin Land Acquisition

2013-2014
Secure Customers and
Finalize Land Acquisition

2014-2016
Construction

2010

2011

2012

2013

2014

2015

2016

Figure 2

The Rock Island transmission line, begun in January 2010, is expected to be placed in service within seven years. Public outreach, regulatory approval, siting, and land acquisition all must precede construction. Image courtesy of Clean Line Energy Partners.

“The main challenge is that you’ve
got distributed regulatory responsibili-
ties. We don’t need just one permit. For
the Rock Island project, we need ap-
proval from the Army Corps of Engineers
for the Mississippi River and other river
crossings; the Iowa Utilities Board for
the authority to build and operate a line
in Iowa; the Illinois Commerce Commis-
sion for the same authority in Illinois;
and then the Federal Energy Regula-
tory Commission regarding the rates
that we will charge for the transmission
lines. And all of those bodies have their
own tests and look at things differently.
It can be quite a challenge to pitch all of
that together and complete those multi-
year regulatory processes.”
The company filed with the Federal
Energy Regulatory Commission for ap-
proval to seek negotiated rates in De-
cember and will file three remaining
permits in 2012.

Detweiler expects the states’ regulatory approval process for the Rock Island line to take about 18 months.

Direct Current (DC): The flow of electric charge in only one direction

Alternating Current (AC):
The movement of electric change
that periodically reverses direction
“And then at the end of the day,
you’ve got to have a product that’s eco-
nomical,” he added.

Manufactured Assemblies
and Components

Most components and assemblies of
the line are common to all types of
transmission lines, he said. “There’s
no difference in a component that’s
carrying a renewable electron versus a
coal-fired electron.”
These include step-up and step-
down transformers, switchgear, system
protection equipment, automation con-
trols, clamps, connectors, battery ter-
minals, and conduit boxes.

The transmission line cost includes
two converter stations that convert the
power from AC to DC near the wind
farms and then back again from DC
to AC in Illinois, at $250 million each,
Detweiler said. “They basically are sub-
stations that have switching yards and
transformers.”
One of the few substation compo-
nents that is unique to HVDC converter
stations is a thyristor, a type of elec-
tric switch (see Figure 3). Thyristors
are all custom-engineered, Detweiler
said. “The manufacturers of the thyris-
tors are the suppliers of the conversion
technology, so there is a high barrier of
entry in that industry. The two leading
producers in the world are Siemens and
ABB,” he said.