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Beyond the headline:

The EIA said a likely factor in the amount produced is wind speeds often peak during the spring in the U.S. On the same day, the Southwest Power Pool, which covers parts of North Dakota to Oklahoma, and the ERC of Texas reported wind penetration records.

The U.S. Energy Information Administration said on March 29, wind turbines in the continental U.S. produced 19% of U.S. energy that day.

At the same time, the EIA noted since the demand for electricity usually dips during the spring and fall, nuclear and coal generators reduce their output or scheduled maintenance during the season. When there is more wind, coal and natural gas generations often reduce their output to match the demand with the overall supply for electricity.

In 2019, wind capacity surpassed nuclear capacity, but nuclear energy usually produces more electricity because of technological differences. On average, the wind usually produces the least amount of electricity each month. The EIA Energy Information Administration does not expect wind power to overtake coal-fired or nuclear generation in any month in 2022 or 2023.

So wind was at peak, while coal and nuclear were idling. Add to that there have been constant additions of wind turbines and shutdowns of coal and nuclear power plants. Also, winds cycles are about 30%-35%, with usually much stronger output (not theoretical "capacity") at night time, when the energy consumption is much lower, so it needs to be captured in batteries or capacitors, while coal and nuclear can be easily ramped up or turned down to match the output needed.

Ask Germany - they could use "diversity" in energy generation right about now.
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