SPP, which has already set six wind peaks this fall, established another on Dec. 19 with 9,948 MW, the second time it has eclipsed 9,000 MW. The RTO said wind’s penetration level was 33.5%, off the record 38.3% set Nov. 4.

ERCOT closed out 2015 with its eighth wind peak of the year, a record 13,883 MW on Dec. 20, representing more than 93% of its installed wind capacity and 44.7% of load served.

The wind generation easily topped the previous peak set Dec. 19, when the ISO exceeded 13,000 MW for the first time with 13,029 MW.

ERCOT generated almost 4.4 million MWh of wind energy in November, accounting for 18.4% of energy used.

— Tom Kleckner