February 23, 2021 – Fossil fuel infrastructure in Texas had to go dark during the unusual deep freeze in the state last week, contributing to a public health and safety crisis affecting millions of Texans and requiring flaring and other processes that will result in high levels of pollution into the atmosphere. 

© Jon Reis / www.jonreis.com

Frank Lomax, an adjunct professor of chemical and biomolecular engineering at Cornell University, is an expert on the production of synthesis gas as well as plant design, construction and safety analysis and has worked on pipeline ice suppression. He says cold weather can lead to solid plugs that interrupt gas pipeline flow, and while pipelines in cold climates are engineered to suppress these plugs, Texas pipelines were not engineered the same way.

Lomax says:

It sounds like the gas distribution system was hit with methane hydrate formation. This is a standard gas pipeline problem in cold climates, and cold weather locations are engineered to suppress the formation of these solid plugs that interrupt flow. Throughout most of Texas, the Southern part of the Midwest and the Gulf Coast, it is very unusual to design pipelines and midstream facilities (the problems here) or refineries and downstream facilities (not related to the power grid) for temperatures below freezing, as these temperatures are unusual, and the temporary interruption when they occur is considered bearable to facilitate lower investment in the fixed assets.

Even without any hydrate problems though, the inability to wheel power into the Texas ERCOT grid and the low level of reserve generating capacity are the real issues. The gas pipeline system is designed and built for a fixed range of flowrates, and as those flowrates are exceeded due to power generation and high home heating demand, pressure must drop.  Any given powerplant can only operate down to a certain design minimum inlet pressure, after which it must shut down to maintain safety. A few plants tripping offline becomes a tragedy only when replacement power can’t be imported, or other plants started to make up the shortfall. Both of those problems were present in the recent brownouts.