SPP Sub-regions & States

SPP North vs. South Sub-Regions

Sub-Region	Key States	Peak Demand	Dominant Resource	Key Constraint
SPP North	NE, KS, ND, SD, WY, MT, CO (east)	~25 GW	Onshore Wind	Export to South and MISO seam
SPP South	OK, TX (panhandle), NM, MO, AR, LA	~35 GW	Wind + Natural Gas	MISO seam capacity, summer peaks

Sub-Region

Key States

Peak Demand

Dominant Resource

Key Constraint

SPP North

NE, KS, ND, SD, WY, MT, CO (east)

~25 GW

Onshore Wind

Export to South and MISO seam

SPP South

OK, TX (panhandle), NM, MO, AR, LA

~35 GW

Wind + Natural Gas

MISO seam capacity, summer peaks

State-by-State Footprint

Oklahoma

Wind capital of the US by installed capacity per capita. Woodward, Elk City, and Clinton areas are the highest-density wind zones. OG&E, PSO (AEP), and WestPlains are key transmission owners.

~12,000 MW wind installed

Kansas

Largest wind state in SPP by total installed capacity. NW Kansas near Nebraska border is increasingly congested. Evergy (formerly Westar Energy and KCP&L) and Empire District are major TOs.

~8,500 MW wind installed

North Dakota

Major wind resource in the northern Great Plains. Basin Electric Power Cooperative and MDU Resources are key SPP members. Bakken region also contributes gas generation. Export constraints to South are binding.

~4,200 MW wind installed

Colorado (East)

Xcel Energy (Public Service Company of Colorado) is SPP's member for eastern Colorado, including the Cheyenne Ridge wind corridor. Among the fastest-growing solar zones in SPP. Western CO is in WECC.

~4,600 MW wind (east CO)

Texas (Panhandle)

The Texas panhandle falls under SPP jurisdiction — distinct from ERCOT's isolated grid. Southwestern Public Service (Xcel subsidiary, SPS) is the primary TO. 6,000+ MW of wind exports to the broader SPP system.

~6,000 MW wind (panhandle)

Nebraska

High renewable penetration relative to load. Nebraska Public Power District (NPPD) and Omaha Public Power District (OPPD) are SPP members. Cooper Nuclear Station is a key baseload asset. Strong solar pipeline emerging.

~4,900 MW wind installed

New Mexico

PNM (Public Service Company of NM) and SPS (Xcel) serve NM in SPP. Growing solar corridor in the Permian Basin and eastern high desert. Wind development concentrated along the NM-TX border.

~3,500 MW wind + solar

South Dakota

Black Hills Corp and Basin Electric serve South Dakota in SPP. Prairie Wind corridor links to Nebraska. Relatively low load — most wind exports south and east.

~1,200 MW wind installed

Wyoming

PacifiCorp (Rocky Mountain Power) is SPP's Wyoming member — partial territory. Wind export focus with limited in-state load. TransWest Express project (proposed) would link Wyoming wind to Nevada/WECC.

~2,100 MW wind installed

Missouri (West)

Ameren Missouri's western portion is in SPP. Eastern Missouri (St. Louis area) is in MISO. SPP-MISO border cuts through the state. Gateway to MISO seam — key export flow point for SPP wind.

~1,100 MW wind (W. MO)

Arkansas

Entergy Arkansas is partly in SPP. State is transitioning from wind-dominant to solar+storage. Strong utility solar pipeline in central Arkansas. SPP-MISO seam runs along the eastern border.

~550 MW wind, growing solar

Louisiana (North)

Northern Louisiana's Entergy service area is partly in SPP. Heavy summer peak demand (cooling load). Solar pipeline emerging in the north. SPP-MISO seam creates flow complexity near the TX/LA/MS border.

~300 MW wind + solar emerging

Montana

Northwestern Energy is SPP's Montana member. Limited interconnection capacity constrains export from Montana's substantial wind resource. Distance from load centers limits economics absent new transmission.

~800 MW wind installed

Iowa (SW Corner)

A small portion of southwestern Iowa falls in SPP territory (MidAmerican Energy service area). The bulk of Iowa is in MISO — the border creates multi-RTO complexity for some projects in the SW quadrant.

~400 MW wind (SW IA in SPP)

SPP Member Utilities — Key Players

AEP Companies

SWEPCO + PSO (AEP)

Southwestern Electric Power (SWEPCO, serving TX/AR/LA) and Public Service Company of Oklahoma (PSO) are AEP's two SPP transmission owners. Combined system: 15,000+ MW. PSO operates the Oklahoma wind corridor transmission backbone.

Oklahoma

OG&E (Oklahoma Gas & Electric)

3,700 MW capacity. Serves Oklahoma City and western Arkansas. Major wind off-taker — owns and operates significant wind generation. transitioning coal plants to wind/solar+storage through 2030 IRP. Key SPP transmission owner in central Oklahoma.

Kansas + Missouri

Evergy (KCP&L + Westar)

Kansas City Power & Light (KCP&L) and Westar Energy merged to form Evergy in 2018. 5,500 MW capacity serving Kansas and western Missouri. Strong wind portfolio in central Kansas. Owns the Abilene hub area transmission.

TX Panhandle + CO

Xcel Energy (PSCo + SPS)

Public Service Company of Colorado (PSCo) serves eastern Colorado; Southwestern Public Service (SPS) serves the Texas panhandle and NM. Both are Xcel subsidiaries and SPP members. Major wind developer and integrator across the western Great Plains.

Nebraska Public Power

NPPD — Cooper Nuclear Anchor

Nebraska Public Power District: 1,900 MW public utility serving rural Nebraska. Cooper Nuclear Station (778 MW) is its anchor baseload asset. Increasingly building wind and solar to meet long-term sustainability goals. SPP's public power anchor in Nebraska.

ND / SD / WY / NE

Basin Electric Power Cooperative

3,200 MW cooperative utility serving North and South Dakota, Wyoming, and Nebraska. Laramie River Station (coal) is its largest asset — scheduled for retirement by 2030. Aggressively building wind to replace retiring coal capacity.