PowerOn Midwest | Technology

Technology

The Preferred Solution

PowerOn Midwest was approved by the Midcontinent Independent System Operator (MISO) as part of its long-range transmission planning portfolio—a set of projects designed to address growing demand, relieve congestion, integrate new sources of generation, and improve grid reliability across the region.

Why 765 kV technology?

765 kilovolt (kV) technology was identified in the planning process as the preferred solution for the region, presenting several advantages:

Efficiently carries power over long distances
Fewer transmission lines needed to carry the same amount of power (see diagram)
Fewer structures reduce impact on land, communities, and the environment
Resilient infrastructure that can consistently deliver power
Provides backup power pathways to deliver energy to customers

A comparison of three types of transmission lines. Left - Six 245 kV single-circuit towers next to each other (900 feet of total right-of-way needed). Middle - one 765 kV single-circuit tower (250 feet of total right-of-way needed). Right - three 345 kV double-circuit towers next to each other (450 feet of total right-of-way needed).

A 765 kV transmission line can carry as much power as six 345 kV single circuit lines or three 345 kV double circuit lines.

Not to scale*

Structure types

Transmission structures play a vital role in the delivery of electricity. They support the components that are used to transport electricity. PowerOn Midwest is working with landowners and the community to power our region today and into the future.

Typical 765 kV structures

This is an example of a typical 765 kV structure, similar to what could be used on the 765 kV segments.

Typical dimensions: width: 140-150 ft; height: 150-175 ft; minimum ground clearance: 60-80 ft; span: 1,100-1,300 ft (approx. 5 structures every mile); footprint size: 35x35 ft to 50x50 ft; foundation depth: 25-65 ft; right-of-way width: 250 ft (125 feet each side from the centerline).

Typical 345 kV structures

These images show the existing 345 kV structures and the new preliminary structures for on the Pleasant Valley to North Rochester segment only.

Existing typical wood and steel H-frame structure (single circuit)

Height: 70-110 ft

Width: 54 ft

Span: 400-1,000 ft

Minimum ground clearance: 26-38 ft

Foundation depth: Varies

Right-of-Way Width: 80 ft

Preliminary typical structure (double circuit)

Height: 90-160 ft

Width: 14-50 ft

Span: 800-1,200 ft

Minimum ground clearance: 26-38 ft

Foundation depth: 30-40 ft

Right-of-Way Width: 150 ft

Land rights overview

Land rights is the name used for the property rights acquired by the utility used for the construction, operation, and maintenance of a transmission line. Most often, the land rights acquired are easements. An easement allows the utilities the right to construct, operate, and maintain a transmission line and other associated infrastructure on a landowner's property.

Our land rights acquisition process

Project representatives will hold individual meetings with affected landowners to discuss land rights.

Utilities contact landowners to begin the easement discussion.
Easement process is discussed with landowners. An offer is based on current market values (similar properties) and other property specifics.
The utilities work closely with the landowner to resolve concerns and reach agreement. If unable to agree, as a last resort, state law provides for an eminent domain process.
The utilities construct, operate, and maintain the transmission line within the easement.

Buy the Farm

Minnesota's 'Buy the Farm' law (Minn. Stat. § 216I.21, subd. 4) applies to the PowerOn Midwest project and it allows a landowner, in certain circumstances, to elect for the utility to buy their entire property (or some portion of it) rather than an easement. Minnesota law also provides certain landowners who make Buy the Farm elections with relocation assistance, which can help ease the burden of moving from a home, farm, or business.