The NYISO Operating Committee has approved two study reports and one study scope, all of which involve load projects in northern New York.  

The SDC St. Lawrence interconnection study modeled the impact of the 120-MW load project on the local system. NYISO staff found that the project would cause thermal overload that could not be mitigated with adjustment. In sensitivity scenarios, the project caused voltage violations and voltage transfer degradation.  

NYISO estimated the cost to build the attachment facility for the interconnection is $55 million, plus or minus 50%, and it would take about 54 months to complete. The cost to mitigate the thermal overload issues and the voltage transfer degradation issues were $33.6 million and $37.5 million. Voltage violations would cost an estimated $2.5 million to mitigate. An additional estimated $39 million would be needed to mitigate thermal issues at the transformer. 

The customer asked if there was a different software package that could be used to help reassess costs. 

“We can take it back and consider it, but I don’t believe the additional capability of the distributed model at St. Lawrence would resolve these overloads” or alleviate upgrade costs, said Aaron Markham, vice president of operations for NYISO.

In the study report for the Massena Green Hydrogen project, a 110-MW hydrogen electrolysis plant, no adverse impacts to the grid were found. NYISO found that interconnection would be feasible with the construction of a new three-breaker and bus substation. The estimated cost for the interconnection would be about $27.7 million, and the project would take two to three years to complete. 

The Cayuga Compute 150-MW data center scoping study was discussed and approved. The study will perform reliability and cost-estimation analysis similar to the reports listed above. 

Other Business

The Operating Committee also heard the July 2024 Operations Performance Report. Peak load was 28,990 MW, which set the new summer 2024 peak. Markham said this was because of higher-than-average temperatures.  

He noted that NYISO also had to call on the Emergency Response Demand Program and Special Case Resources during the evenings of July 15-16. Markham said they hit scarcity pricing on both days. 

“On the 16th of July, a number of severe thunderstorms, including 10 confirmed tornadoes, occurred in the state as the remnants of Beryl passed through,” Markham said. He said that caused simultaneous outages for about 275,000 customers.

“There was a tornado in Buffalo early last week, and from what I saw, that broke the [record for the] number of tornadoes that occurred in the state,” Markham said. “That was 25 back in 1992; we are up to 26 this year.”  

The committee also reviewed and approved supplemental manual updates for constraint-specific transmission shortage pricing. These updates to the day-ahead scheduling manual and transmission dispatch operations manual are described here. Drafts may be seen here and here. 

Eds: A previous version of this article incorrectly referred to the SDC St. Lawrence as the North Country Data Center.