NYISO reported Monday that locational-based marginal prices (LBMPs) for June averaged $31.76/MWh, nearly unchanged from May but up 16% from June 2016. Year-to-date monthly LBMPs averaged $36.01/MWh through June, a 20% increase from a year earlier.

In a July 24 Market Operations Report to the ISO’s Business Issues Committee, Rana Mukerji, senior vice president for market structures, said natural gas and distillate prices fell from the previous month but gained 27.5% year-over-year. Natural gas prices at Transco Z6 NY averaged $2.35/MMBtu in June, down from $2.80 the previous month.

Gulf Coast jet kerosene for the month came in at $9.59/MMBtu, down from $10.47 in May, while ultra-low sulfur No. 2 diesel at NY Harbor was $10.14/MMBtu, compared with $10.82. Distillate prices dropped 5.4% from a year ago.

On Capacity Exchange, Probabilistic Method not Better

A new probabilistic method to limit capacity price increases caused by exports from an import-constrained area would complicate the process and offer results no better than the current deterministic method, according to an analysis conducted for NYISO by GE Energy Consulting.

Mukerji shared the analysis from the monthly Broader Regional Markets Report as the latest development arising from FERC’s January acceptance of the ISO’s capacity revisions while rejecting a proposed one-year transition as lacking an “analytical basis” (ER17-446). A NYISO analyst briefed stakeholders on the outlines of the study at the April Business Issues Committee meeting. (See NYISO Provides Update on Capacity Export Concerns.)

NYISO proposed the plan last fall to address anticipated price spikes in the capacity market in the Lower Hudson Valley and New York City zones expected after the commission in October allowed a New York plant in a constrained zone to export into ISO-NE. (See FERC Sides with ISO-NE in Capacity Dispute with NYISO.)

The new rules use a locality exchange factor to reflect how much capacity from “rest of state” can replace capacity exported from an import-constrained locality. The prior rules assumed that 100% of a generator’s exports from an import-constrained area must be replaced with generation in that locality.

“The probabilistic method introduces uncertainty and does not give results which differ significantly from the 47.8% found using the current deterministic method,” the analysis said. That figure represents an estimate of the percentage of exports from NYISO zones G-J to ISO-NE that could be expected to be replaced by “rest of state” capacity. NYISO compromised with an 80% figure.

Stakeholder comments on the methodology analysis were due by July 14. FERC in its January order encouraged a robust stakeholder-driven process but said “we cannot accept NYISO’s proposal for a one-year transition based solely on stakeholder support.”

— Michael Kuser