Wind generation in November blew through a 31-month-old record share of total energy in the Electric Reliability Council of Texas, a new report shows, and an expert said it contributed to ERCOT’s low on-peak power prices that month.

Wind farms supplied 18.4% of the independent system operator’s total load in November, compared with October’s 12.3%, last November’s 15.1%, and the previous record high of 15.2% set in March 2013.

The latest numbers are from ERCOT’s 2015 Demand and Energy Report, released late Thursday.

Jeff Schroeter, managing director of Plano, Texas-based Genova Power Advisors, said Monday that wind generation availability, weather and low natural gas prices converged to create a “perfect storm” for low power prices in ERCOT this November, which accrued to “ratepayer benefit and generator detriment.”

Day-ahead on-peak power at the heavily traded ERCOT North Hub averaged $21.90/MWh in November, down 6.7% from October and down 43.6% from November 2014, according to Platts data.

Asked whether wind generation contributed to November’s low prices, Schroeter said in an email, “Yes — wind generation availability due to weather and capacity additions, bid strategies and the energy-only market converge with ultra-low gas prices.”

Day-ahead natural gas prices at the Houston Ship Channel, which ERCOT uses as a local benchmark for cost estimates, averaged $2.051/MMBtu this November, compared with $2.352/MMBtu in October and $4.006/MMBtu in November 2014, according to Platts data.

In contrast with wind’s increased share, natural gas- and coal-fired generation supplied decreasing percentages of power in November, compared with October. Natural gas’ share fell from 47.9% in October to 44.5% in November, while coal’s share fell from 30.4% to 27.2%.

Overall, demand fell almost 13% from 27.5 TWh in October to about 23.9 TWh in November, and this November’s total demand was down 2.9% from the November 2014 total of 24.7 TWh.

Read the rest at Platts.com