Abundant natural gas supply and low price volatility have meant that for the second year in a row, no gas storage facilities were added in the United States, according to the U.S. Energy Information Administration (EIA).
Small capacity changes, both up and down, at existing storage fields meant that the nation's storage capacity remained essentially flat over the last year, according to the agency, which measures storage capacity every November.
Decreased seasonality in natural gas prices is the main reason for a decline in the value of gas storage capacity and a lack of developer interest in adding new capacity. Relatively low and stable prices, as well as substantial on-demand supply can be attributed to the productivity of the nation's shale gas basins.
FERC recently declined to extend a certificate for a long-delayed storage capacity addition in Mississippi (see Daily GPI, March 15). One year ago, the Federal Energy Regulatory Commission refused to allow Tres Palacios Gas Storage LLC to abandon capacity for which it could not find a market (see Daily GPI, March 19, 2015). Earlier this year storage operator Houston-based Ryckman Creek Resources LLC and its parent, Peregrine Midstream Partners LLC, filed for Chapter 11 bankruptcy (see Daily GPI, Feb. 5).
Excitement for the seasonal arbitrage game with underground gas storage might be gone, but existing storage facilities are still humming along. EIA uses two measures of natural gas storage capacity.
Design capacity is the sum of the working gas design capacity at 385 active storage fields, as of November 2015, as reported in the agency's monthly gas storage report. Design capacity is based on the physical characteristics of the reservoir, installed equipment, and operating procedures particular to the site. Because of slight changes at existing fields and the deactivation of 10 facilities, design capacity declined slightly, falling 0.2%, from 4,665 Bcf in November 2014 to 4,658 Bcf in November 2015.
The other measure, demonstrated maximum working gas volume, is the sum of peak volumes reported by the 385 active storage facilities in the Lower 48 states, regardless of when the individual peaks occurred, over the five-year reporting period ending in November 2015. This measure is compared to the five-year period ending November 2014. At the national level, the difference is small, increasing by just 0.1% from 4,336 Bcf to 4,343 Bcf.
In addition to geographical regions, EIA categorizes storage based on geology. Traditional storage, such as depleted fields, provides the bulk of storage by volume, and it typically is filled during the spring, summer, and fall, and then is withdrawn during the winter.
Increasingly popular is salt cavern storage, which consists of leached caverns in salt deposits, mostly along the Gulf Coast. While far smaller in volume, salt storage, unlike depleted fields, can be cycled in and out many times a year.
Because of this seasonal usefulness, salt facilities in the South Central region saw a significant increase in demonstrated working gas volumes between November 2014 and November 2015, rising by 5.8%, as many salt facilities hit new peak levels in November, EIA said. By contrast, traditional storage in the adjacent Mountain region saw a significant decrease, falling by 6.3% because a few facilities that reached peak levels in 2010 are no longer included in the five-year period ending last November.