With temperatures dipping into the single digits, National Grid customers are using about 60 percent more natural gas than they would if the thermometer was reading in the 30s.
Based on the weather forecast, that demand is projected to increase this Friday and Saturday. Nonetheless, the demand should not outstrip the supply Liz Arangio, National Grid Director of Energy Procurement, said in an interview Tuesday.
Arangio said the system is designed to accommodate peak demands. She said that the volume provided by the Algonquin and the Tennessee pipelines aren’t sufficient during severely cold days. It is at this time that National Grid turns to liquefied natural gas (LNG), which in Rhode Island is stored in two tanks. The Providence tank, with a capacity of 2 billion cubic feet, is on Allens Avenue and is visible from Route 95. A smaller tank of 200,000 cubic feet is located in Exeter.
Arangio said the tanks, which act as a reserve to meet those periods of peak demand, have the capacity to accommodate 20 to 30 days of drawdown during normal winter weather before being fully depleted and would last 10 days if used every day. She was careful not to call the LNG a reserve.
“We plan to use the LNG always, so it's not as if we have a reserve margin. We plan to use it on the peak days, always. I guess if you could get enough pipe in the ground to displace that, selfishly from a gas supply perspective, I think that would be terrific, and then you would have LNG as reserve in the event you had any pipeline issues. That would be ideal, but it would be a significant level of pipeline to be put in the ground in order to do so.”
Arangio would not disclose the inventory status of the tanks at this point or guess how much more cold weather the system could handle before implementing a curtailment program. Under the curtailment program, customers with alternate energy sources would be taken off the system first. From there, commercial customers would be impacted, with residential customers the last to be affected.
“We plan the portfolio and gas supplies to meet these weather requirements, so albeit very cold, we do plan to have enough supplies to last these cold days,” she said.
“We see a warm trend coming,” Arangio said of longer-range forecast.
Tony Russo, Project Director for liquefaction project and former manager of RI LNG Operations, said the Providence tank is manned 24/7 and is ready to augment the pipeline supply. He said that the tanks are refilled at the end of the winter season by tanker trucks, a system that National Grid is looking to replace. National Grid is going through the permitting process to build a plant to liquefy natural gas to replenish the tank. Russo is hopeful of having the system operational by 2020.