Ontario GA Rates Keep Climbing — What It Means for Class A Timing

Global Adjustment rates in Ontario have trended upward over the past several years, driven by contracted generation costs, nuclear refurbishment commitments, and conservation program spending that flows through the GA pool. For Class A customers, this means the financial penalty for missing a coincident peak — or the reward for catching one — keeps growing.

A few years ago, the difference between catching all 5 peaks and missing 2 might have been $80K for a mid-size facility. Today that same miss can cost$120K or more, simply because the GA pool is larger. The peak demand factor math hasn’t changed, but the dollars behind each percentage point of PDF have increased.

This is worth flagging because it shifts the ROI calculus for peak prediction systems. More aggressive curtailment strategies — accepting more false alarm days in exchange for higher recall — become financially justified as the per-peak value increases. A curtailment event that costs $3,500 in lost production looks different when the peak it might catch is worth$40K vs. $25K.

For facilities still using the “curtail every hot day” heuristic, the rising GA rates also make the false alarm cost more visible. At 30+ curtailment days per summer, the operational disruption adds up. The case for a more precise prediction approach — fewer alerts, better targeting — strengthens every year the GA pool grows.