Wind power in Texas: The tail that wags the power grid dog

Image Credit: Daxis/Flickr (CC BY-ND 2.0)

Hi everyone!

Greetings and Happy New Year from blogHOUSTON!

We started off the year in a classic Texas manner when Houston (and Texas as a whole) went though a massive plunge in outdoor temperatures starting during the late hours on New Year’s Day 2022. Temperatures in Houston during December 2021, as the Houston Chronicle breathlessly reminded us, made for the warmest December on record. Many of my friends on social media joked about how warm it was during Christmas and New Year’s. That all ended when the cold front we are experiencing now passed through. It wasn’t what I would call a true Blue Norther, as the skies in front of the cold front did not quite have the dark hue that a true Blue Norther has. However, temperatures fell some 40-50 degrees over a span of 12-18 hours, and for all other intents and purposes it was our first Blue Norther of the season. We were fortunate in that this cold snap was a dry one, and not accompanied by heavy winds or precipitation.

One thing about this cold snap that I’ve been watching closely is the Texas electrical power grid, directed by ERCOT. Most readers of blogHOUSTON will know what ERCOT is, but a quick reminder is that ERCOT is the entity that oversees some 85-90% of the electrical power grid in Texas. Last February, Houston (and Texas) was struck by perhaps the fiercest cold snap in our history, resulting in millions of Texas residents losing power for several days. The latest official count is that 246 people died during the event. Several hundred lawsuits are still pending because of what happened. Ever since, some Texans have been jittery any time a weather anomaly occurs, fearing that the power grid will lock up again and that we will lose power.

The Summer of 2021 electrical power outages that never happened

Months later in June 2021, ERCOT put out a public statement urging Texas residents to conserve power due to an unexpected number of plant outages during the upcoming summer. Pandemonium broke out, with the Democrats going on the warpath, saying that Republicans couldn’t keep the power running.

Yet, a funny thing happened on the way to summertime Hell. The Houston area (at least) had probably the coolest summer in recent memory. I did a survey of Houston weather between June 1,  2021 through October 1, 2021 using data from the Weather Channel. During the 122-day timeframe from June 1 through October 1, Houston officially had zero days of 100-degree weather. By my counting, Houston had 5 days in which the high temperature reached 80 degrees or less, 38 days where the temperature only got up to between 81-90 degrees, 63 days of between 91-95 degrees, and only 16 days in which the high temperature got up to 96 degrees or higher. In other words, the much ballyhooed fear of the Texas electrical grid collapsing right in the middle of the Houston summer never happened, as one might say we got a much needed reprieve from God (or Mother Nature).

The New Year’s 2022 electrical power outages that never happened either

Likewise, when this recent two-day New Year’s cold snap came on the horizon, hysteria once again broke out. The Houston Chronicle wrote several posts reminding Houstonians of last year’s freeze and questioning whether the electrical grid was ready. Well, we’re pretty far along with this event, and no, there haven’t been any blackouts. Indeed, as I write this, the statewide power demand is only at 48 gigawatts and the highest demand there has been over the past two days is at 52 gigawatts. There’s plenty of electrical power available, and at this point it’s pretty safe to say that the grid and the various reforms that were pushed through during the past 2021 Texas Legislature passed their first serious test with flying colors.

On the variations in electrical power generated from wind power

Given that I’ve been watching the power situation somewhat carefully over the past 6-7 months since ERCOT’s warning last spring that we might need to conserve power, one thing I’ve definitely noticed is how much the quantity of power supplied by wind power sources varies, even within a span of one day. Below is a series of graphs, downloaded from the ERCOT website, indicating how much power was being forecast and actually generated from wind power.

Here is a reading I took on July 11th, 2021:

Here is a reading from July 21st, 2021:

Here is a reading from July 26th, 2021:

Here is a reading from July 30th, 2021:

Here is a reading from August 4th, 2021:

Here is a reading from August 14th, 2021:

Here is a reading from October 4th, 2021:

Here is a reading from October 20th, 2021:

Here is a reading from October 29th, 2021:

Here is a reading from December 4th, 2021:

Here is a reading from January 2nd, 2022:

What sticks out in these readings is how it isn’t unusual for power generated from wind sources in Texas to fall 75% or more from peak power generated during a 24-hour time period. Indeed on some days such as October 4th, 2021, the amount being generated was less than one gigawatt, although there were other days on which the amount of power being generated reached over 15 gigawatts. Moreover, it is not uncommon for peak power generation from wind to occur during the middle of the night, when power demand is least. Likewise, the converse holds for when the quantity demanded is highest, which usually is during the late afternoon hours between 3:00pm – 6:00pm (when power generation from wind is at its low point). In other words, we are often getting power from wind when we need it least, and not getting it when we need it the most.

It should be clear to even a casual viewer that relying on power generation using wind is very problematic for powering an affluent society that has long been accustomed to reliable electrical power. One possible way to mitigate this would be to employ batteries to store power as it is being generated during the night for use later on during the day. Even then, however, there are still issues such as what happens if there is an overall slowdown in winds, which was the case recently in Europe. If that occurs, then no amount of battery infrastructure is going to help.

Moreover, these huge variations in electrical power generation from wind present serious problems for all other players in the Texas utility game. If electrical power generation from wind is so intermittent, that means that there had better be enough power available from other sources to make up for when the winds die down. Heavy reliance on wind power for electricity presents problems that ultimately have to be dealt with by using other power sources, and hence is an issue that others are forced to work around. Hence, my reason for titling this post that wind power has become the tail that is wagging the dog that is the Texas electrical power grid.