Working US natural gas storage in the Lower 48 states totalled 2,866 billion cubic feet (Bcf) as of September 28, 2018, which is the lowest working natural gas stocks have been at this time of year since 2005.  Getty Images photo.

October can be a pivotal month for adjusting seasonal US natural gas storage levels

This article was published by the US Energy Information Administration on Oct. 5, 2018.

Working US natural gas stocks in the Lower 48 states totalled 2,866 billion cubic feet (Bcf) as of September 28, 2018, which is the lowest working natural gas stocks have been at this time of year since 2005.

If October net injections to working natural gas stocks match the five-year average, inventories will total 3,208 Bcf on October 31, which is lower than EIA’s September Short-Term Energy Outlook projection of 3,270 Bcf.

October can be a pivotal month for adjusting seasonal US natural gas storage levels.

If summer injections into natural gas storage fields are lower than typical levels, natural gas injections in October represent a late season opportunity to increase stocks before winter begins.

Alternatively, if natural gas stocks are already higher than multi-year averages, it can be operationally difficult to inject more natural gas into storage fields because of rising pressure levels; higher field pressures can limit injections.

The pace of natural gas injections may accelerate during October because of several factors.

Many local distribution companies have regulatory requirements to reliably meet a range of winter natural gas demand scenarios. Natural gas in underground storage is one way in which local distribution companies satisfy this requirement.

Cooler weather in October should moderate natural gas needs to generate electricity to meet air conditioning load and potentially make more natural gas available to inject into storage. Current lower than typical natural gas inventory levels at underground natural gas storage fields mean that spare capacity is available for increased injections.

Historically, October tends to be the third strongest month for injection activity into working natural gas storage, behind May and September.

Since 2013, Lower 48 net injections have averaged 307 Bcf in October compared with 408 Bcf in May and 343 Bcf in September, during the same period. The largest net injection ever reported for the entire month of October occurred during the 2014 refill season (400 Bcf).

The figure shows net injections during October since 2003, and the lower panel shows working gas levels on September 30, heading into the final month of the refill season.

The upper panel shows that a net injection of 474 Bcf would be required to reach the September STEO’s projected Lower 48 inventory (3,270 Bcf).The largest reported one-month net injection total, was 494 Bcf in May 2014.

The Lower 48 states will still enter winter with its lowest level of working natural gas stocks since the 2008–09 season (3,399 Bcf) if October 2018 net injections reach 400 Bcf.

Lower 48 net natural gas injections during October since 2003Lower 48 working natural gas inventories as of September 30 since 2003

Source: U.S. Energy Information Administration, Natural Gas Monthly, Short-Term Energy Outlook (September 2018), Weekly Natural Gas Storage Report.