Explainer: transmission adders, credits and the alternative 'ball-and-stick' method in the JTS RFP

During the briefing, advisory staff walked commissioners through how the Phase 1 decision proposed to account for transmission impacts when scoring bids and what the alternative methodology would change.

Under the Phase 1 framework, projects that would trigger additional transmission investment would be assigned transmission adders that increase their evaluated cost, while projects that interconnect inside constrained areas or to distribution could receive credits that lower their evaluated cost. As Wheaton explained, "Such a bid might be assigned a transmission adder that would make the project look more expensive than it otherwise would have been."

The small stakeholder transmission group proposed two paths: Option A would recalculate adders and credits consistent with the Phase 1 decision; Option B would replace the adder/credit system with a new "ball and stick" methodology. Public Service's draft RFP indicates the company intends to use Option B but stated it was still studying Option B and might revert to Option A if necessary.

How it affects bidders: The choice changes how projects are comparatively scored for their transmission impacts and could advantage projects located in lower-transmission-cost locations or those that interconnect to distribution, depending on which method is used.