Electricity networks and green energy ambitions
One way to think about the power grid that nearly collapsed in Texas on Wednesday evening is as a form of growing pain; The state’s population increased by about 800,000 people between 2020 and 2022, which is equivalent to about 45% of the increase in the total population of the United States. Meanwhile, Texas manufacturing has rebounded, and the critical oil and gas industry has recovered from damage from the pandemic.
It’s no wonder the 10 highest days ever of demand on the state’s power grid occurred this year. The first day, August 10, saw a maximum load of 85.6 gigawatts, according to Grid Status, the data provider. That’s more than 10 gigawatts higher than the pre-pandemic peak in 2019, about 20 gigawatts more than the peak in 2018, and it’s not even close, according to Andy DeVries, a veteran utility analyst at CreditSights.
The surprising development is that on Wednesday, when the grid operator declared a Level 2 emergency, the load did not reach a record high, recording about 83 gigawatts that day, and did not even reach the top ten. But he set a different kind of record: net load. That’s the demand on the grid after wind and solar production, which peaked at 70.7 gigawatts on Wednesday evening, around 7:25 p.m. local time, just around sunset, so you’d expect a rapid decline in solar power.
Indeed, there was a decrease of 6.6 gigawatts during the previous hour. At this time, there is a sudden drop in network frequency, which usually indicates that demand exceeds supply. There was a sharp drop in frequency before the blackout during the Texas blackout disaster in the winter of 2021. The resulting damage, and the potential for frequency variations to become self-reinforcing, likely explains why the grid operator quickly declared a state of emergency, which ended after about an hour.
On one level, this seems quite clear. An unusually warm day in Texas kept air conditioners running longer into the evening even in the absence of solar power, which led to tighter conditions. However, the tendency for solar energy to stop when everything gets dark is predictable, so there is still a bit of mystery about this drop in grid frequency. There was also some lull in wind power around 7:25 p.m.
After falling by about 1.3 GW over the previous 30 minutes, wind generation had bottomed out for the evening at that point, so that could be one explanation. On the other hand, Texas also experienced an unusually high level of power outages at conventional power plants this summer, so it’s possible that one or more of those plants could be tripped offline unexpectedly.
However, this near-miss reminds us that the largest state electricity market in the United States is under pressure from several, sometimes conflicting, directions. The first is the dramatic increase in electricity consumption, which requires the rapid construction of new power generation and transmission plants. Another reason is climate change, which will likely bring more extreme weather to Texas over time (and not just in the summer), increasing energy demand. The third reason is the energy transition aimed at tackling climate change.
Texas, like California, has benefited from the renewable energy boom but has also struggled to accommodate its occasional fluctuations. Wind and solar generation achieve minimal variable costs because no fuel is burned, which suppresses electricity prices, as happened during the heat wave in Texas in late June. However, they do require backup during periods of high net load, such as hot summer evenings, usually with batteries, but currently, they are usually natural gas-powered peak plants.
Politically, this presents a problem for the Texas governor and the Republican majority, which seems ambivalent at best about green energy, despite the current abundant capacity and the state’s potential for more. The state Legislature passed a measure this summer that would provide funding for new dispatchable peak plants — not renewables or batteries — to support the public grid.
*A writer specializing in energy and commodities affairs.
Published by special arrangement with the Washington Post Leasing and Syndication Service.
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