Hurricane Florence affected the natural gas market last week as lower electricity consumption resulted in decreased natural gas consumption by natural gas-fired electricity generators. Although Florence made landfall on Friday, September 14 as a Category 1 hurricane, it remained over the Carolinas as a tropical storm through Saturday night, causing numerous power outages and reducing demand for electricity. According to Genscape data, the volume of natural gas delivered from interstate transmission pipelines to electric utilities in North Carolina and South Carolina decreased by 0.8 Bcf/d on Saturday, September 15 compared to the previous week―September 7–13―when deliveries averaged 2.0 Bcf/d.
The National Hurricane Center warned that life-threatening storm surges and catastrophic flooding would accompany Hurricane Florence. The storm made landfall at 7:15 a.m. Friday near the North Carolina-South Carolina border then moved slowly along the South Carolina coast; Florence was downgraded to a tropical depression on Sunday. Because of widespread power outages, peak electric loads over the weekend were 30%–35% lower compared to the previous weekend―September 8–9.
According to EIA’s Hurricane Florence Status Report published the morning of Saturday, September 15, more than 800,000 customers in North Carolina (16%) and 95,000 customers in South Carolina (4%) were without power. However, Duke Energy has confirmed that almost 1.7 million customers experienced an outage as a result of Hurricane Florence. As of Tuesday, September 18, EIA estimated that 6% of customers in North Carolina and less than 1% of customers in South Carolina remained without power.
Duke Energy, which includes Duke Energy Carolinas and Duke Energy Progress East and West, accounted for about 75% of the estimated 0.8 Bcf/d decline in natural gas consumption. Since Monday, however, deliveries to electric utilities and power plants have increased to 2.3 Bcf/d on average, according to data from Genscape, which is slightly higher than the levels observed in the previous week. Natural gas use by electricity generators is now 10% higher than pre-storm levels, which offsets a 3 gigawatt (GW) decline in the availability of nuclear capacity. The 1.86 GW Brunswick nuclear power plant, located 4 miles from the coast near Wilmington, North Carolina, shut down its units on Thursday, September 13 in preparation for the storm and remains offline. An additional 1.16 GW of capacity is offline as the second unit at the McGuire nuclear plant undergoes planned maintenance.
Nuclear energy is the primary electricity-generating fuel in North Carolina and South Carolina, accounting for 43% of total electricity generated in the two states in 2016. Although coal (26%) accounted for a larger share than natural gas (24%) of net electric power generation in 2016, natural gas has since surpassed coal in both states. In May 2018, natural gas accounted for 30% of net generation in North Carolina and 16% of net generation in South Carolina while coal accounted for 24% and 13%, respectively.