The Plains & Eastern Clean Line transmission project will deliver 4,000 megawatts (MW) of clean energy generated from the Oklahoma Panhandle region to utilities and customers in Arkansas, Tennessee, and other markets in the Mid-South and Southeast, areas that lack access to low-cost, renewable power. The project will deliver enough energy to power more than one million homes per year in the Mid-South and southeastern United States.
Plains & Eastern Clean Line is regulated by the Oklahoma Corporation Commission and Tennessee Regulatory Authority. As a transmission owner and operator, Plains & Eastern Clean Line will also be regulated by the Federal Energy Regulatory Commission. In addition, Plains & Eastern Clean Line will be required to obtain permits from a variety of state and federal agencies, including the U.S. Army Corps of Engineers. Plains & Eastern Clean Line must also follow the rules and requirements specified in by the United States Department of Energy’s as part of its decision to approve the project.
The Federal Energy Regulatory Commission (FERC) will have oversight of the terms and conditions of service and the rates charged and will have a role in ensuring that the project’s transmission lines are operated fairly. FERC has approved Plains & Eastern Clean Line’s rate structure and granted Clean Line authority to negotiate with potential customers.
The Plains & Eastern Clean Line is currently under development. Construction. The Plains & Eastern Clean Line is expected to begin delivering electricity as early as 2020.
Clean Line’s intent is to provide new wind generation facilities access to markets with a growing demand for renewable energy, which is why we are locating the resource area converter station where wind energy is most cost competitive. Legally, transmission companies are not allowed by the Federal Regulatory Commission (FERC) to prohibit certain types of energy, but as a practical matter, wind energy is the resource that would be economically advantaged by a project like this. It would not make sense to build a coal or nuclear power plant a long distance from a load center when you could produce the electricity much closer to the demand.
In 2014, Clean Line conducted an open solicitation pursuant to its FERC negotiated rate authority. Clean Line received requests from fifteen different potential transmission customers for 17,091 MW of transmission service, nearly four times the Project’s total transfer capacity during the initial open solicitation window. Since then, several respondents have increased the size of their capacity requests. To date, Clean Line has received requests for a total of 22,190 MW of transmission service, over five times the Project’s total transfer capacity.
The Plains & Eastern Clean Line will be responsible for bringing on line over 4,000 MW from new clean energy projects that otherwise would not be built due to limitations of the existing electric transmission grid. The energy may come from multiple wind farms built by different developers in the Oklahoma Panhandle region.
Since 2010, Clean Line has pursued a multi-step routing process that incorporates best practices for siting linear infrastructure to avoid and minimize impacts from the project. Clean Line has conducted extensive public outreach involving landowner, community leaders, agency representatives and other stakeholders and is committed to minimizing impacts to existing land use in accordance with environmental, cultural, and engineering considerations. Clean Line believes that a process that involves seeking input from those affected by the project is critical to the ultimate success of the Plains & Eastern Clean Line. Through direct outreach with the public and coordination with public agencies and non-governmental organizations, Clean Line solicited stakeholder input to refine and identify the proposed right-of-way for the direct current transmission line.
Routing along existing linear infrastructure (such as other transmission lines, roads, and pipelines) or property lines is widely accepted as a best practice because it helps to minimize new fragmentation of existing land use and habitats; however, we must balance that with the potential impacts on land use in the area as well as other applicable criteria.
When paralleling existing transmission lines, our right-of-way would typically be adjacent to (but not overlapping) the existing rights-of-way. When doing so, Clean Line will maintain safety clearances as dictated by the National Electrical Safety Code and applicable state and local codes.
Guyed structures with supporting wires will typically occupy 10-15% of the easement area due to the space requirements of the supporting wires.
The land under the transmission line can be used for crop production and pasture/grazing lands. Most crops less than ten feet tall may be grown safely under power lines. Clean Line must comply with the National Electrical Safety Code to ensure the safety of the general public and North American Electric Reliability Corporation Standards to ensure the reliable operation of the transmission line. As a result, vegetation growing within the easement area must be limited in height to maintain safety and reliability standards..
Since some easements may be very small in size, Clean Line will pay landowners a minimum easement payment of $2,000 per parcel, regardless of the size of the easement area on their land. In the event that no structures are constructed on a landowner’s parcel, the landowner will also receive a minimum structure payment.
Prior to formal negotiations with a landowner, a market study is performed within each county along the proposed right-of-way by a certified independent appraiser to determine the average fair market value of different land use types within each county. These average fair market values and specific characteristics of each parcel are reviewed to determine the fair market value for each easement along the proposed right-of-way and to determine whether an appraisal is required under the Uniform Act. If an appraisal is required under the Uniform Act, a qualified real estate appraiser employs standard appraisal practices to determine the fair market value of the easement. The appraiser evaluates the characteristics of the property and easement rights being acquired and examines available market data of comparable, recent sales in the same geographic area. Each landowner will be notified of such an appraisal and is encouraged to accompany the appraiser during inspection of the property to identify and discuss any features of the property that the landowner believes have bearing in the determination of the fair market value of the easement.
Trees and other vertical vegetation that pose a threat to the safety or reliability of the transmission system will need to be cleared or managed in order to comply with NERC standards for vegetation clearance distances. Landowners will be given the option to keep the felled trees.
Clean Line would like to know if you have a home in the current proposed right-of-way; please submit information to your land agent along with a map reflecting your information.
Every landowner’s property is different, and without knowing all the specifics it is difficult to say definitively what impact, if any, the proposed transmission line would have on a property. However, the relationship between transmission lines and property values has been the subject of systematic research for nearly 50 years. Clean Line commissioned Tom Priestly to perform a review of this body of research. His review concluded that these studies show that being close to electric transmission lines can have little or no negative long-term effects on residential property values, with average impacts ranging from no effect on value to a decrease in value of up to 10 percent. All that said, landowners will be compensated for 100% of the fee value of the land in which the easement area is located and will receive additional payments if they have structures on their land.
Historically, the transfer of electricity between regions of the country has been over high-voltage alternating current (AC) transmission lines, which means that both the voltage and the current on these lines move in a wave-like pattern along the lines and continually change direction. In North America, this change in direction occurs 60 times per second (defined as 60 Hertz [Hz]). The electric power transmitted over AC transmission lines is exactly the same as the power we use every day from AC outlets but at a much higher voltage. Over the past 40 years, high voltage direct current (HVDC) transmission lines have been constructed that offer significant electrical, economic, and environmental advantages over AC transmission lines for long distances. DC transmission is especially suited for integrating and transporting power generated by various renewable energy sources. Unlike an AC transmission line, the voltage and current on a DC transmission line are not time varying, meaning they do not change direction as energy is transmitted.
Direct current (DC) is the preferred technology for moving large amounts of power over long distances. The use of a DC transmission line results in overall higher efficiency and reliability than an equivalently sized alternating current line to move the same amount of power, therefore offering significant electrical, economic and environmental advantages. These advantages include lower power losses on the line, smaller footprint than AC lines that carry similar amounts of energy, and the ability to control the power flow.
Converter stations are required for each of Clean Line’s projects to convert power from AC to DC or vice a versa. The DC converter station in the wind resource area is used to convert the incoming AC power generated by the wind farms into DC power. The delivery converter station on the other end converts DC power into AC power to be delivered to customers through the existing AC grid. The delivery converter station in Arkansas can both deliver into and pick-up energy directly from the state.
The project will include three converter stations: one at each endpoint and an intermediate delivery converter station in Pope County, Arkansas.
Under normal operations a bi-pole high voltage direct current (HVDC) transmission line requires a return path for very small current imbalances. During emergency operations or certain maintenance operations when one pole is out of service, the full load current will flow through this return path. In some existing HVDC transmission lines, this return path is via ground electrodes. The Plains & Eastern Clean Line project will utilize a third set of conductors (wires) on the transmission structure referred to as the dedicated metallic return conductor. Therefore, during bi-pole or monopole operations, all current will be contained within conductors on the project, and will not flow through the earth below.
We anticipate the majority of the structures will typically be between 110 and 150 feet tall. However, the exact height of the structure depends on several variables, including: engineering requirements, topography, structure type, and span length. Generally, the taller the structures, the greater the span between structures; and, the shorter the structures, the shorter the span between structures. This means if structures are at the taller end of the 110 to 150 foot range; there typically will be fewer of them. Instances when the structures could exceed 150 feet in height include river crossings or terrain that would require longer span length.
EMF stands for electric and magnetic fields. Electric fields are produced by voltage, and voltage is the electrical pressure that drives an electric current through a circuit. Magnetic fields are produced by current, and current is the movement or flow of electrons. EMFs are naturally present in the environment and are present wherever electricity is used, for example a toaster, cell phone, a battery operated device, a lamp, a computer, etc. The earth has both magnetic fields produced by currents in the molten core of the planet and an electric field produced by electrical activity in the atmosphere, such as thunderstorms.
For more information on electromagnetic fields and HVDC transmission, please click here to download a fact sheet.
Several studies have assessed the impacts on agricultural operations of stray voltage, along with electric and magnetic fields, corona and air ions. According to an epidemiological study of 500 herds of Holstein dairy cattle, herd health, measured using multiple indicators, did not differ between periods before and after a nearby +/- 400 kV direct current line was energized. These results did not vary based on the herd’s distance from the high voltage direct current power line. Another study conducted by Oregon State University titled “Joint HVDC Agricultural Study” determined that no differences were found between cattle and crops raised under+/-500 kV direct current lines and those raised away from the lines. A report by the Western Interstate Commission for Higher Education also determined that a +/- 400 kV direct current transmission line did not affect crops, vegetation, or nearby wildlife, nor were the electric and magnetic fields from the line felt by persons walking in the right-of-way.
The Plains & Eastern Clean Line will bring substantial economic benefits throughout the project region. It is estimated that the Plains & Eastern Clean Line will result in thousands of direct construction jobs building the transmission line, associated facilities, and new wind farms and hundreds of permanent jobs maintaining and operating the transmission line and the associated wind farms. Additionally, businesses will see increased demand for their products and services, particularly those involved with services, materials and equipment to be used in construction of the project and the associated wind farms, as well as retail and hospitality industries.
The development and construction of the Plains & Eastern Clean Line is estimated to cost roughly $2 billion. Clean Line will finance the transmission lines and will sell transmission capacity to wind energy developers that wish to transmit their energy to market, and to utilities that choose to buy the low-cost clean energy delivered by the line.
If a large majority of the capacity is not sold, then the project will not be built. We would have in place the entirety of the construction financing prior to commencing construction.
Yes. The construction of a transmission line of this size generally requires the use of oversized vehicles and machinery. Clean Line recognizes the risks associated with heavy traffic on county and local roads. We will minimize the impact of these vehicles to existing road networks and will repair any damage caused by construction activities. Clean Line will work with the state departments of transportation and county officials and engineers to plan road use during construction.
We will work to prevent and/or mitigate agricultural impacts associated with the construction process. Reclamation activities that may be implemented on impacted areas include, soil removal, soil de-compaction, soil fertilization, erosion prevention, and repair of damaged soil.
Clean Line will consult with landowners and/or tenants to identify the location and boundaries of agriculture or conservation reserve lands and to understand the criteria for maintaining the integrity of these committed lands. Additionally, Clean Line will work with landowners and/or tenants to identify specialty agricultural crops or lands (e.g., certified organic crops or products that require special practices, techniques, or standards) that may require protection during construction, operation, or maintenance. Clean Line will avoid and/or minimize impacts that could jeopardize standards or certifications that support specialty croplands or farms.
Clean Line will negotiate with landowners interested in hosting such facilities.
Staging areas are typically located within the ROW and are used as miniature multi-use construction yards.The components for a few structures may be arranged in a staging area immediately before they are assembled. Staging areas will not be common, due to the extra work involved in the off-load and on-load of structure parts (double-handling). Construction crews will naturally minimize handling time and costs, usually by transporting components directly to each structure location.
In some instances, weather, topography, other environmental factors, or construction activities such as pulling and tensioning of the conductors may require activity outside the staging areas or ROW. These specific instances will be discussed with landowners in advance and will only take place where such use is permitted.
A staging area is displayed in the construction simulation video on the Plains & Eastern Clean Line website in order to demonstrate what this area may look like when used.
There will be a mixture of temporary and permanent roads—though permanent roads in cropland would be highly unusual. Clean Line will negotiate the nature of access roads with landowners, and the landowners will be compensated accordingly.
Roads not otherwise needed for maintenance and operations will be reclaimed to preconstruction conditions. Reclamation practices may include decompacting, recontouring, and re-seeding. Roads needed for maintenance and operations will be retained.
Construction crews will make an effort to access the right-of-way easement from public roads that intersect or are adjacent to the right-of-way. Once an access road is established, construction will follow the right-of- way to the next access road location, which preferably will be located at the next public road crossing. In some instances, depending on topography or other environmental conditions, off-right-of-way access may be needed to facilitate construction or maintenance of the line.
Prior to the beginning of operations, Clean Line will develop a Transmission Vegetation Management Plan which will define site-specific standards, measurable metrics, and vegetation management objectives; and prescribe controls or treatment options (e.g., mechanical, biological, or chemical) to achieve defined objectives that support the goals of an integrated vegetation management framework.
Additionally, on organic farms, no herbicides, pesticides, fertilizers, or seed would be applied unless approved by the landowner.