With autumn approaching much of the US, it won’t take long before cold weather begins again in some parts of the country. Texas residents could be forgiven for the idea that triggers a bit of PTSD, given that last winter saw a near-collapse of the state’s power grid, leaving many residents with no cold weather at all. Left without any power for days.
A long list of factors contributed to the disturbances, and in the immediate aftermath, their relative importance was difficult to discern. But now, grid regulators and governance groups have produced a preliminary report on the incident, along with some recommendations to avoid future disasters. A central conclusion is that the grid failure was tightly coupled to the failure of the natural gas supply – as natural gas processing facilities were among the places where their power cuts occurred.
The preliminary report has been put together by the Federal Energy Regulatory Commission (FERC) in conjunction with the North American Electric Reliability Corporation, a nonprofit established by utilities to help set standards and practices that keep the grid stable. Is. The draft itself is not being released at this point, but both have posted a detailed presentation which describes the content of the report. A final version will be released in November.
The outline of February’s grid problems is well understood: a severe cold raised demand at the same time as it caused several production sources in the affected region to fail. The problems affected several states, but only Texas’s ERCOT grid suffered serious failures. Neighboring Southwest Power Pool faced five hours when demand exceeded its generation capacity, but due to its tighter integration into neighboring grids, it was able to call on 13 gigawatts of generation capacity in the states formerly.
Texas’ grid is poorly integrated with the rest of North America, so it didn’t help much. As a result, demand exceeded capacity for three consecutive days, with the biggest deficit being 20 GW. For over four minutes, the ERCOT grid’s frequency dropped from the standard 60 Hz to 59.4 Hz. Had ERCOT stayed on that frequency for five more minutes, additional production sources would have gone offline, sending all ERCOTs into a widespread blackout.
The biggest single cause of failures during the event was frozen equipment, ranging from varying gauges and instruments on large plants to the icing up of wind turbine blades. It accounted for 44 percent of the failure to build the equipment. Mechanical failures account for another 20 percent. Between the two was a fuel supply failure, which accounted for about a third of the failures. And here “fuel supply” refers primarily to natural gas.
when the gas does not flow
During the peak of the cold snap, Texas saw a 71 percent drop in natural gas production. Processing of natural gas for distribution declined by 82 percent. Part of this is certainly a drop in supply. But apparently that’s not all, given that the processing is finished in two days. before this Compensated. There were many reasons for failure, including equipment freezing and mechanical failures due to freezing.
But a major problem was the lack of electricity in the gas distribution and supply system. Apparently, Texas grid operators had taken no steps to identify natural gas facilities and prioritize power distribution to them when the rolling blackout began. “Most of the natural gas production and processing facilities surveyed were not identified as having significant loads or otherwise protected from load shedding,” the report indicates.
This started something of a snowball effect. As processing and handling equipment loses power, the supply of natural gas drops, causing gas-fired power plants to shut down, further cuts to power supplies, and potentially further damage to gas infrastructure. There are even more cuts. As of yet, the full extent of power cuts in natural gas infrastructure is not clear, and it is not certain that we will know by the time of the final report.
to do list
The report makes 28 recommendations for change in response to these failures, nine of them called key recommendations. The most important of these amendments is recommended NERC Reliability Standards, which shows what is expected of North American grid operators. Modifications include new plants built to handle operating temperatures that include the extreme weather events experienced at that location and retrofitting existing sites accordingly. The generators will also be expected to inform the grid operators how much capacity will be available based on forecasted weather conditions.
Other reliability standard revisions should ensure that natural gas infrastructure is protected during load-shedding incidents and that any cold-operated failure on the grid triggers the production of a corrective-action plan.
In addition to revising reliability standards, several other recommendations focus on the supply of natural gas. Any facility that collects or processes natural gas is advised to have a cold-weather plan as well as a supply of heating and backup electricity. Cold weather forecasts should also trigger inspections of these systems.
Beyond these concrete recommendations, there is a long list of things that should be studied. One of the simplest is that ERCOT must consider strong interconnection with the surrounding grid, which proved to be crucial in preventing widespread failures in neighboring states.
Of course, many of these recommendations could have been made the last time ERCOT saw a major failure nearly a decade ago. This failure was also bad enough to trigger analysis and recommendations by FERC. Finalizing the report in November will be of little importance for action in the coming years compared to ensuring its recommendations. Fortunately, it seems the head of FERC recognizes this. A similar investigation took place after extreme cold weather in Texas in 2011, but those recommendations were not acted upon,” said FERC President Rich Glick. “We cannot allow this to happen again. This time, we must take these recommendations seriously, and act decisively, to ensure that the next time extreme weather hits, the bulk power system does not fail.”