Texas grid should meet power demand today: Update

Updates with information from ERCOT

Texas' electric grid operator said it is able to handle demand today and has instructed all utilities to restore power to customers, but warned of more freezing weather expected tonight.

The Electric Reliability Council of Texas (ERCOT) last night directed utilities to bring all of their customers back on line after enough generation became available to meet demand. Utilities restored power to more customers overnight, with the total number of outages in the state dropping from as much as 3.3mn yesterday to about 503,000 as of 12:30pm ET, according to outage tracker PowerOutage.US.

As of 12pm ET any remaining outages across the state are largely a result of downed power lines from the winter storm, but in some cases stem from power transmission that needs to be manually turned on by maintenance crews, ERCOT senior director of operations Dan Woodfin said.

As of 12pm ET about 23.5GW of thermal power generation — which includes natural gas, coal and nuclear plants — was off line in Texas, down from 26GW earlier this morning, with 16.5GW of renewables unavailable, down from 18GW.

The grid has enough generation to meet demand today in part because business and industrial demand has not come back amid the historic storm that has paralyzed the state and kept the vast majority of citizens at home amid unsafe road conditions. ERCOT expects utilities will begin implementing true rolling outages today to keep demand consistent with what generation is available, as opposed to the long-lasting shutdowns experienced across the state in recent days.

"We do not have a role in determining where rotating outages are implemented," ERCOT chief executive Bill Magness said. "We tell transmission owners we need a certain amount of demand reduced."

Woodfin said he has not looked at how much natural gas-fired power generation remains off line today as a result of a lack of gas supply resulting from well freeze-offs or low pipeline pressure, as ERCOT's focus has been on preserving the generation that is operating. The natural gas power plants that are unavailable "went out fairly soon" as freezing temperatures descended into the state early this week because of restricted natural gas supply, icing or because they tripped off line, Woodfin said.

Renewables, nuclear rebounding

A variety of generation has come back on line, including a large amount of solar generation yesterday, he said.

The 1,250MW South Texas 1 nuclear reactor is also ramping up power, with output at 36pc today compared with zero yesterday, according to the US Nuclear Regulatory Commission. The unit shut on 15 February after its cooling water intake froze.

Today about 6.5GW of wind is powering the grid, which is close to the seasonal amount expected during peak conditions, Woodfin said. About 16GW of wind generation is unavailable because of frozen turbines.

ERCOT is wary of forecasts for more freezing weather across the state overnight and said the winter event is long from over.

"We still expect a high cold weather peak tomorrow morning," Mangess said. "We think we are in a glide path and we hope that those customer restorations happen. If we do hit a bump and have to come back off we believe we will be at a level where it is not the large numbers we faced earlier this week."

The grid operator expects that regulation may occur regarding the winterization of power plants to avoid frozen equipment leading to widespread outages during winter storms in the future. The state requires all generators to submit a weatherization plan, but there are no specific requirements on what those plans must include or any standards that they must meet, Woodfin said.

Houston, north Texas restorations

The Houston area, where about 1.4mn customers were out yesterday, reported 31,000 customers out as of 12:45pm ET, according to local power distribution company CenterPoint Energy. Oncor Energy, which serves parts of north Texas that includes the Permian basin, reported about 178,000 customers without power, down from as much as 1.1mn customers.

ERCOT at 8:30pm ET yesterday said it continued to make progress on restoring power and had been able to restore about 8,000MW of service, representing about 1.6mn households, throughout the day yesterday.

Yesterday afternoon the operator said it had sufficient generation available to begin restoring 1,000MW each hour.

Crews have struggled to perform crucial work on natural gas production sites, processing plants and pipeline equipment in order to fuel gas-fired power plants in Texas, many of which are also inoperable from icy conditions.

Natural gas pipeline companies have reported a gradual increase in gas flow as maintenance progresses on wellhead freeze-offs and frozen equipment, the oil and gas regulator the Texas Railroad Commission said.

Some well sites reported the inability to produce gas because they did not have power, the Texas Railroad Commission said yesterday evening. Producers also reported bad road conditions that were keeping crews from reaching leases.

By TL Hamilton