SPP has an interconnection queue that holds 681 active requests totaling 140 GW today. That is nearly three times the 52 GW the queue has connected since the queue’s inception in 2002. Withdrawals have already cleared out far more: 2,058 requests, totaling 420 GW, never completed.

Oklahoma and Kansas account for half of these active requests. Oklahoma leads at 39 GW, ahead of Kansas at 27 GW and Texas at 18 GW.

Thermal is the largest technology at 35 GW, followed by standalone BESS at 31 GW, solar at 29 GW, and wind at 24 GW. Hybrids add another 20 GW, almost all of it solar paired with storage. Counting co-located storage, BESS requests total 49 GW.

Nearly half the queue, 67 GW across 341 requests, already holds a signed interconnection agreement. However, another 37 GW still sits at DISIS entry, where the odds of developers discontinuing applications are high. Surplus and ERAS carry a further 29 GW outside the standard cluster process.

Unlock the rest of the article to find out:

• How much of the 140 GW queue we forecast reaching commercial operation by 2031, by technology.
• Which SPP zones take the largest share of new capacity and BESS.
• How likely a request is to withdraw at each stage of the queue.
• How long SPP projects take to come online, and how the forecast accounts for delays.

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Key takeaways

• 15.8 GW of BESS is expected by 2031, up from about 1.4 GW operating today.
• Co-location dominates. Surplus, hybrids and shared POIs account for 12.7 GW of the BESS expected by 2031.