Little Rock-based Southwest Power Pool, the regional transmission organization that manages the electric grid for much of the central United States, recently set records for the highest share of electricity demand supplied by the wind in one hour and one day at 72% and 62%, respectively, according to the U.S. Energy Information Administration (EIA).
Wind power met 29% of the organization’s electricity demand in 2019. The power provided a high of 37% of electricity demand in October and a low of 18% in August. The share changes as a result of fluctuations in wind output and total electricity generation.
The wind penetration rate, or the amount of electricity demand met by wind generation, reached 62% on March 7. Between 1 and 2 a.m. April 27, the wind penetration rate was 72%. The wind penetration rate can be expressed as wind generation’s share of electricity demand or total generation.
System operators such as Southwest Power Pool are responsible for balancing electricity supply and demand in real-time, according to the EIA. The organization uses its energy generation resources to meet demand and takes part in energy trade with neighboring system operators for economic or reliability factors. Net electricity interchange, or electricity imports or exports to or from the region, comprised about 2% of the organization’s generation in 2019.
Wind penetration records are typically broken in the spring because of seasonal patterns in electricity demand and wind power output. In the organization’s region, wind generation is usually highest in the spring. Also, spring is a time when electricity demand is low because of mild temperatures, leading to lower energy use to heat or cool homes. Electricity demand is also lower on weekends, which is when the recent records were set.
Wind generation follows daily patterns, and land-based wind generation is the greatest overnight when stronger winds often happen. Wind power records are usually set in the early morning hours.
Southwest Power Pool has been investing in wind power capacity, and as of March, the organization had 21 gigawatts of the capacity, comprising 24% of its total generation capacity and 20% of the total utility-scale wind generating capacity in the United States, according to the EIA.
Across the organization’s system, electricity consumption had fallen up to 10% as a result of electricity use changes amid the COVID-19 (coronavirus) pandemic, according to recent news releases. As of June 1, the organization’s membership had risen to 100 members for the first time. Barbara Sugg, the organization’s president and CEO, recently announced staff would return to the office in September. Staff have been working remotely since mid-March when efforts began to mitigate the spread of COVID-19.