If we ever have to survive a grid-down scenario, how long will Natural Gas last without electricity?
How Long Will Natural Gas Last Without Electricity
The natural gas feeding your house gets its compression from higher pressure “transmission” gas lines. Natural gas has pressure coming straight out of the wellhead, but it needs help to get to its ending destination, your house. The gas is piped from these lines through “regulator stations”, belonging to your natural gas provider, which step down the pressure to the lines going to your home. At your meter is another regulator which also may step down pressure to your home.
The vulnerability and fragility of our current electric grid time and again is showcased in an unfavorable light.
But what about the natural gas grid? It’s underground, fairly redundant, and so far has a decent reputation for reliability.
What are Natural Gas’ flaws?
The Federal Energy Regulatory Commission (FERC) and the North American Electric Reliability Council (NERC) commissioned and produced a report, titled “report on the Outages and Curtailments During the Southwest Cold Weather Event of February 1-5, 2011” after the Southwest Cold Weather Event of February 1-5, 2011.
The potential deficiencies noted, in the natural gas grid, need to be addressed across the entire U.S., and not just in the Southwest.
Distance from Gas Heads
Distance is one of these flaws. The pipeline transmission system, aka the “interstate highway” for natural gas, consists of 220,000 miles of high-strength steel pipe, 20 inches to 42 inches in diameter. This pipe highway moves vast amounts of natural gas thousands of miles from producing regions to local natural gas utilities and sometimes directly to large users of natural gas. There are compressor stations every 75 to 100 miles to boost the pressure, that is lost due to the friction of gas moving through steel pipe.
The Natural Gas pipeline network extends across the entire country.
Natural Gas’ Reliance on Electrical Grid
Another of the major flaws of Natural Gas grid is it’s dependency on the electric grid.
The gas grid relies on electricity. The gas grid requires that pressure must be maintained throughout the system. This pressure is maintained via a system of compressors and pumping stations.
The good news is that some of the main compressor stations, feeding the large interstate pipelines, are typically fueled by natural gas and generate their power with it, to keep operations running. Gas-fueled compressors could be more widely used throughout the system, but they are noisy and have environmental implications. So in urban areas, the gas distribution companies typically use electric pumps and compressors to bring gas to the consumer. It’s not hard to see where the problem lies here. No electricity, no gas supply.
If you are lucky enough to live along a line that is powered by it’s own natural gas, you should still have some pressure pushing gas down the line, as long there are no breaks in the line.
Electrical Grid’s Reliance on Natural Gas
The electric grid relies on natural gas. In the U.S.A., natural gas powers almost a third of the electricity generation plants. With the discovery of enormous shale gas reserves and the low prices of natural gas, that number is growing quickly. Almost all new conventional electrical generation on the books in the USA is natural gas-fired.
There are also vulnerabilities pertaining to gas service, especially during extremely cold weather.
These weather issues start in the field where the gas is collected from wells and routed into the feeder pipeline system. This process can be disrupted by ‘freeze-offs’. Freeze-offs occur when water that is co-produced with methane, crystallizes or freezes, blocking the gas flow and shutting wells.
“Freeze-offs” routinely occur in cold weather. Too many freeze-offs can result in a loss of pressure to the pipeline. If the pressure gets too low, the distribution companies start cutting off customers to maintain adequate pressure. They first curtail service to marginal areas most likely to fail, and simply shut meters.
Unlike the electric grid, which can be restored fairly quickly, once the main problems are fixed, gas restoration is a slow process.
- Teams must close all the meters,
- Purge the system with air
- Re-pressurize with gas
- Teams must visit every location to relight pilot lights and ensure safety.
In the February incident of 2011, 32,000 customers in New Mexico were without gas service, taking days and millions of dollars to restore.
Hurricane Sandy in 2012 compromised the New Jersey coastal natural gas delivery system, with over 1,000 leaks on Long Beach Island alone. According to New Jersey Natural Gas officials, they could not cut gas service to the Island, because if they did it would take over six months to bring service back online, under current government regulations.
What can you do with Natural Gas
Some gas stoves don’t require electricity, except for the light bulb in the oven. Each top burner is approx 6,000 BTU, so doing some cooking or boiling some water can really warm up the kitchen on cold days.
There are generators that run on natural gas. With a properly sized unit, a localized power outage would have almost no impact you on.
Natural Gas fireplaces can provide a good amount of heat to a room or area of a house. Properly vented gas fireplaces, that can be manually lit, is a nice source of emergency heat. Some of the newer gas fireplace units with remote controls do require electricity.
Most tank type gas water heaters still have thermocouple pilots, so hot water will be available. In a power outage situation you can keep the bathtub filled with hot water. A 30 gallon tub will put 13,750 btu’s into the house if allowed to sit and give up it’s heat in an hour. The water heater is typically rated at 40,000 input Btu so if you can find a creative way to use this energy you can get some heat in the house. Running the shower for a few minutes can also provide some heat and utilize the energy stored in the water heater.
Most central heating units will not work, since they require a fan and electric controls.
How long do I have?
While the natural gas grid seems to be more resilient than the aging, electrical grid, it’s dependance on it means that your natural gas probably won’t last much longer than your electricity, in a true grid-down scenario.