Utilities gear up plans to deal with any repeat of last winter’s natural gas upset

With winter’s arrival Southcentral Alaska utilities are taking steps to ensure that a repeat of last winter’s near-failure of natural gas supply for heating and power generation doesn’t happen again.

Enstar Natural Gas Co. is drilling new wells at its Cook Inlet gas storage facility near Kenai to improve its ability to produce stored gas during a cold snap and regional electric cooperatives like Matanuska Electric Association and Chugach Electric Association are providing new backup and adding resiliency to electric distribution systems.

The problem last year occurred when mechanical problems developed in two gas of five wells at Enstar’s gas storage, limiting the withdrawal of gas. This happened during a sharp cold snap in late January.

Utility managers worry that a drop in gas pressure in distribution lines would cause furnaces to shut off, as well as a drop in gas supply to fuel power stations.

Luckily this didn’t happen. It took some time but Enstar was able to repair the wells and made plans to drill two new ones. One new well is finished and a second is in progress, Enstar CEO John Sims said in a briefing last week.

Meanwhile, Chugach and MEA have installed battery storage to protect their systems against glitches that could upset the power as well as short-term backup in case of a total blackout. The battery will also reduce use of natural gas by a small amount.

MEA spokesperson Julie Estey said her cooperative, which serves the Mat-Su region, also has diesel generating backup at its Eklutna power plant in case of a natural gas disruption.

“We can seamlessly switch to diesel at any one of our 10, 17.1-megawatt engines at the Eklutna Generating Station. We have two holding tanks with three days of fuel on hand if the plant is running at maximum capacity, so that’s typically four to five days depending on our load,” or the demand for power, Estey said.

MEA also has access to hydroelectric power from the Eklutna and Bradley Lake hydro facilities that can be ramped up, she said.

“This was a big help during the (natural gas) deliverability issue last February and will increase with the development of the Dixon Diversion,” a project to add hydro capacity at Bradley Lake, Estey said.

If it proceeds, this project can add new renewable power by 2030 but it won’t help in the near-term.

Chugach Electric is also working on plans to add natural gas storage at the Beluga gas field, which is on the west side of Cook Inlet and within the Matanuska-Susitna Borough. The Anchorage-based cooperative owns the majority share of the Beluga field in a partnership with Hilcorp Energy and now has a capability of storing about 2.5 billion cubic feet in the field.

The plan is to expand this to 20 billion cubic feet, which would be a major expansion of stored gas for Chugach in addition to its share of the 11 billion cubic feet of gas stored in the Kenai gas storage facility operated by Enstar.

“Another highlight for reliability is that MEA participated in an emergency preparedness exercise on gas deliverability issues a few weeks ago with our partners at the other utilities, including ENSTAR, Hilcorp, the borough, the Municipality of Anchorage and others,” Estey said.

“We walked through the options to keep the gas pressures stable during a deliverability event, such as to stop selling power to Fairbanks (to save natural gas), use hydro, purchasing power from Fairbanks, and requesting big loads (major customers) to go to back up generation.

It was great to bring everyone together to feel prepared,” she said.