Coordination of Texas electric and natural gas sectors key in dealing with blackouts

Energize Weekly, January 10, 2024

Better coordination between the Texas electric and natural gas industries is key to getting individual generating facilities up and running – a so-called blackstart – after a cold-weather blackout, according to a federal report.

The joint study by the Federal Energy Regulatory Commission and the North American Electric Reliability Corp. was done in the wake of the widespread blackouts caused by Winter Storm Uri.

“Winter Storm Uri, the severe weather event of February 2021, will long be etched into many Texans’ minds,” a report by the Texas comptroller said, as 69 percent of the state lost power at some point during the six-day freeze.

The state’s independent grid or system operator, or ISO – the Electric Reliability Council of Texas – relies on natural gas for 42 percent of its power generation. During Storm Uri, the combination of subzero temperatures and blackouts stalled the gas industry from wellhead to compressor to pipeline.

“The electric and natural gas industries are heavily reliant on one another to maintain operations; in most cases, natural gas cannot be produced, processed, or transported without electricity, and most blackstart and next-start resources within the ISO operate with natural gas as their primary fuel,” the joint study said.

The study team said it found a “lack of adequate information exchange between electric and natural gas entities” as to the availability and status of natural gas infrastructure in the state.

This information gap creates a risk to the grid operation to maintain the reliability of the bulk electric system, especially during emergencies such as a blackstart.

“Open lines of communication in place between the two industries in preparation for a blackstart system restoration scenario is necessary to facilitate timely restoration of the electric grid,” the report said.

A blackstart is the ability of a generating unit to restart without the support of the connected grid. There are two basic elements to it: the ability to operate in cold weather and sufficient fuel or power to do so.

Many generating units – particularly ones using natural gas – were inadequately weatherized and froze during Storm Uri.

In the aftermath, the Texas legislature passed a bill requiring generating plants to winterize. The joint report found a host of initiatives taken by operators.

One generating unit participant updated its entire winterization process, while another found that increasing glycol levels in its heating systems helped to prevent freezing issues, with no impact on its summer operations.

Another increased staffing, while several added remote temperature monitoring, and some insulated exposed equipment.

The joint report said that backup batteries and interconnections to other grids can also provide blackstart resources. “The team believes that with ongoing improvements in battery technology, batteries could make valuable contributions in emergency operations,” the report said.

As for ensuring fuel, the two main options are storage and fuel switching, although the system remains heavily dependent on natural gas.

Generating units with dual-fuel capability typically use distillate oil as their alternate fuel. This alternate fuel is generally delivered via trucks.

“While blackstart resource options like fuel diversity may be limited in this region,” the report said, “reliance on a single fuel source, such as natural gas without natural gas storage or firm supply and transportation contracts, could cause significant issues during blackstart system restoration.”

The report calls for incorporating off-site natural gas storage in blackstart restoration plans.

“The natural gas supply chain may be severely stressed or completely unavailable during a blackstart system restoration scenario,” the report said. “Stored natural gas may increase the likelihood of blackstart.”