Network upgrades: the reinforcement a new generator triggers

Network upgrades are the additions and modifications to the transmission system that an interconnection request makes necessary. They are distinguished in the pro forma agreements from interconnection facilities, which are the equipment between the generating facility and the point of interconnection.

The distinction matters because the two categories are treated differently for cost purposes. Interconnection facilities are the interconnection customer''s responsibility. Network upgrades are funded by the interconnection customer under the cost allocation rules in the applicable tariff, and become part of the transmission system owned by the transmission owner.

Upgrades identified in a cluster study are commonly shared: several projects contribute to the same constraint, and the cost is apportioned among them under the tariff''s allocation method. When a project withdraws, the upgrades it triggered are reassessed and the remaining allocations change, which is why withdrawal rules and restudy provisions are litigated as closely as the engineering.