Reliable Power from Reliable Fuel

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The US economic infrastructure depends heavily on the use of energy. Fuel diversity helps mitigate fuel risk for businesses, consumers, and industries against factors like price fluctuations, delivery infrastructure problems, new environmental policies, and regulations.

The three leading fuels for power generation in the US are coal, natural gas, and nuclear power, with wind and solar power providing a fraction of power to the grid. Stationary industrial engines have traditionally run on diesel for power, a fuel source that tends to fluctuate in price and availability. In recent years, however, natural gas has become a viable option for both primary grid-level electricity production and onsite generators.

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Natural gas is gaining popularity across a range of industrial applications. Influencing factors include:

  1. Stability and reliability compared to other fuel sources
  2. Natural gas is more cost-effective
  3. Natural gas burns cleaner
  4. The natural gas infrastructure is resilient, even during severe weather

It can be argued that natural gas usage contributes to the national security of the US. The US is the largest producer of natural gas in the world, making it a clean, reliable source of energy without the risks of foreign entanglements.

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A Stable and Reliable Fuel Source
While it is a non-renewable resource, natural gas is a consistent and stable energy resource. Unlike renewable sources such as wind and solar, which are not easily dispatchable to meet variable demands, natural gas turbines and engines can ramp up quickly to meet variable loads at any time of day. One of the major remaining challenges with renewables is matching peak production times with peak demand. The peak electrical demand typically occurs several hours after peak solar photovoltaic output. Great progress is being made on grid-scale energy storage, but it is still an expensive proposition to store more than a few megawatt-hours (Mwh) of energy.

The capability that natural gas power plants have to adjust relatively quickly to changing demand complements the variable output from renewables, improving overall grid stability. It’s not a perfect carbon-neutral solution, but it’s technically feasible and economical to implement on a utility scale.

To help understand why natural gas is a reliable and stable source, it is important to know the state of natural gas delivery in the US and how it operates. Natural gas is delivered by underground pipelines connected to the utility’s main supplies that connect to the end-user. For a simpler visual, these underground pipelines can be compared to the US highway system, with thousands of pipelines stretching thousands of miles.

There are three main parts to the national gas system: the gathering of the gas from multiple small wells, the transmission of the gas by long-distance pipelines, and the distribution of the gas to local customers.

Natural gas is formed from decaying organic matter mainly found on the ocean floor in shale formations and solid waste treatment facilities (biogas). Once sources are found, wells are drilled for extraction and facilities are built for processing into pipeline grade natural gas. From there, the natural gas infrastructure takes over, reliably delivering natural gas to the end-user.

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Credit: Generac Industrial Power
Three paralleled natural gas gensets back up a regional electrical distribution company.

Lower-Cost Solution
In addition to its stability, natural gas is also a cost-effective solution to provide energy for backup power sources. Natural gas delivers the lowest operating cost per kilowatt-hour (kWh) produced compared to any other source of fuel—beating out wind, solar, coal, and nuclear power. An abundance of natural gas led to even lower prices in 2016. Costs were estimated to be down by 17% compared to the year before.

Natural gas is a domestic fuel, which means it can be found in the US rather than having to go overseas to source. The stability of having this source close to home means that international affairs will rarely affect the amount of natural gas available, reducing price volatility due to global political instability.

While it is not a new technology, fracking has become more cost-effective and companies are able to tap into underground natural gas resources more easily and efficiently. In spite of the controversy about fracking technology, it is the main factor that is leading the US much closer to energy independence.

Also adding to the price differentiation between diesel fuel and natural gas is the cost of fuel maintenance. The cost of fuel polishing, a treatment that must be done at least annually to keep the diesel fuel storage tank free of “sludge,” can cost $1 to $2 per gallon. Even though diesel engines are often less expensive initially, when you compare the fuel costs annually and account for all of the soft costs in mind, natural gas comes out as 50–60% less expensive per kWh produced.

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Credit: Generac Industrial Power

The Cleaner Option
In the age of green, businesses are constantly pursuing ways to implement environmentally friendly practices into their day-to-day procedures. According to the International Gas Union, natural gas is one of the cleanest fossil fuels when it burns, meaning it can greatly reduce a business’ carbon footprint. Compared to oil and coal, the emissions of sulfur, nitrogen, and carbon dioxide (CO2, a greenhouse gas) are considerably lower. When burned, natural gas releases 50% less CO2 than coal, and 20–30% less than oil.

This 50% reduction in CO2 emissions decreases manufacturing “smokestacks,” meaning less air and water pollution. This is an immediate benefit for manufacturing plants and the surrounding communities.

Safety and Resilience, Even During Extreme Weather and Power Outages

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Credit: Generac Industrial Power
A complete backup paver system powered by natural gas supports a supermarket facility.

Perhaps the biggest argument to be made for natural gas to power backup energy sources is its resilience, even during times of severe weather. Up until a few years ago, natural gas was frequently overlooked and avoided, often because of the incorrect perception of its durability.

The reliability of natural gas over onsite diesel storage has been documented and shows that natural gas sites are expected to operate weeks or months, depending on the gas storage during given times of the year, whereas onsite diesel storage typically only supplies up to three days.

Natural gas pipelines are also less likely than diesel fuel delivery systems to be compromised during major disasters, including most seismic events. Following a major natural disaster, roadways are often impassable, and diesel fuel supplies can be limited. Due to this, available delivery personnel and trucks are often unable to keep up with emergency demand, and diesel fuel users have much less control over their fuel source.

Take Hurricane Sandy for example. In October 2012, patients were evacuated from both New York University Langone Medical Center and New Jersey Palisades Medical Center because backup diesel generator systems failed to operate. Flooding had caused so much damage that access to liquid petroleum was virtually impossible.

Historically, there are very few outages in the natural gas distribution system. A technical report by MIT cited that firm delivery contracts exhibit greater than 99.9% reliability when it comes to the natural gas distribution system.

Authorities Having Jurisdiction (AHJ) are now beginning to accept natural gas generators as a sole offsite fuel source because these generators rely on a strong underground pipeline network that is rarely impacted by weather. The large network of natural gas pipelines, paired with the diversity of gas supply and storage options, provides resiliency in the event of a localized failure. The networked transmission and distribution systems enable operators to reroute the gas supply from alternative production sources or pipelines.

Taking into account these four factors, many companies in the commercial and industrial sector have started shifting to natural gas usage to power both their business-as-usual operation and emergency engines. Due to its convenient location and high production rate, it provides a reliable fuel source. The cleanliness and stability of natural gas eliminate fuel maintenance costs and reduces other system maintenance costs compared to diesel fuel. Reduced CO2 emissions, low cost, and resilient delivery infrastructure continue to drive use and acceptance of natural gas as an industrial fuel. De Bug Web

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