Tenaska witness says Conestone substation allows 500 MW interconnection with minimal upgrades

Mister Latham, a company witness, told the Public Service Commission that Tenaska’s interconnection team used PJM grid models and identified the Conestone substation as a location where “we could put 500 megawatts of capacity onto the grid charging and discharging without significant network upgrades.”

Commissioner Suchman said the zone is constrained and asked whether Tenaska had discussed constraints directly with BGE; Latham said the firm had prior discussions with BGE in the past but he did not recall asking the specific constraint questions that would show whether Conestone is the system-optimal site. Suchman said that, because ratepayer money could support the project, she expected clearer engagement with the utility before locating the project on a greenfield site.

The witness cautioned that his role was not as the interconnection engineer who performed the detailed study, and he said the team used PJM models to test where the capacity could be delivered. He also noted the proposed site sits roughly 600 feet from the substation, which he cited as a factor that limits the need to build new transmission lines. Commissioners pressed for evidence the company had assessed whether brownfield alternatives could meet both interconnection and siting goals.