Four Ways Texas Gas and Power Suppliers Can Protect Against the Coming Freeze

(Bloomberg) -- When a deadly cold seized Texas nearly one year ago, desperate power companies burned mesquite in barrels and blasted propane torches to keep their equipment from freezing. Still, large swathes of the grid went dark as instruments iced over and gas production came to a halt, leaving millions without electricity and heat for days. 

Now, with an arctic blast again threatening Texas with below-freezing temperatures, power and gas suppliers are under pressure to prevent a repeat of last year’s catastrophe. While the gas supply network — the lifeblood of the power system — has yet to complete many of the proposed changes meant to protect it from extreme weather, there are plenty of routine steps operators can take to keep the lights on. Here are some of them:

Keep equipment warm

One of the cheapest ways gas operators can prevent freeze-offs is by wrapping surface equipment, valves, water lines and other equipment with insulated packing material to guard against colder temperatures. They can take it a step further by using heating blankets, catalytic heaters, fuel line heaters and insulated steam systems to protect flow lines, though these methods would be costlier.

Insulation and heating can keep instruments at power plants from freezing, too. During last year’s freeze, one South Texas utility burned mesquite in barrels to warm up exposed units that otherwise would have iced up and broken down. Another revved up diesel-fired heaters and propane torches to keep generation capacity from faltering. Wind turbines sometimes have their own heating systems, but many operators in Texas have chosen to forego those for all but their newest turbines, according to BloombergNEF wind analyst Oliver Metcalfe. 

READ ALSO: Texas Had All Year to Prep for Cold, and It's Not Ready

Erect physical barriers

“Wind walls” erected around gas compressors and other equipment can provide some protection against inclement weather, but precipitation can still make contact with equipment from above, so icing could still shut down facilities.

Eliminate water vapor

Water vapor is a menace to gas equipment during cold weather, wreaking havoc on operations and disrupting fuel flows when it turns to ice.

Pipeline operators can prevent this by pumping methanol into the gas stream, which lowers the freezing point of liquids and prevents them from eaching small orifices where they can gum up operations. But there are a few barriers to deploying methanol. First, electricity is needed to keep pumps flowing, so if power is cut to gas fields — as happened during the 2021 freeze — methanol will be useless. Second, getting the methanol on site can be challenging if roads are too hazardous to drive on. During last year’s storm, many roads were impassable so methanol couldn’t be delivered. Adding glycol when natural gas is flowing through a piece of field equipment known as a “contactor” also can absorb water vapor and allows dry gas to pass through. 

Natural gas held in storage tanks can be filtered through a dry bed or molecular sieve that absorbs water and prevents freezing. High-pressure filters can also remove water and particles before the fuel arrives at instruments and control panels.  Finally, drip valves on pipelines allow moisture to secrete before the fuel arrives at instruments. These tools may not be available to all operators, however. 

For wind turbines, anti-ice coatings can deter freezing. Some turbines have special operating modes that change the pitch of blades when they accumulate ice. But both are costly to install after a project starts operating, said BNEF’s Metcalfe.

Deploy backup power

Since last year’s crisis, some utilities have received authorization to acquire backup generation that would enable them to essentially create microgrids that would power small areas in the event of another massive blackout. 

Some crude oil and natural gas production sites also have diesel or other types of backup power systems that keep equipment running in the event of a power failure on the grid. But, “there’s no way to prepare for 100% of all conditions,” said Ed Longanecker, president of the Texas Independent Producers & Royalty Owners Association. “The best weatherization is keeping the power on.”

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