Natural gas is a non-renewable resource that is relied on across the globe for several applications. In 2021, roughly 4.04 trillion cubic meters of the resource were consumed worldwide. Due to its significant drawbacks, such as its non-renewable nature, carbon emissions, and pollution, renewable natural gas is becoming a popular alternative.
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The main difference between the two resources is that renewable natural gas is, as described, renewable. While traditionally, natural gas is obtained by drilling into the ground, renewable natural gas is derived from natural routes of organic matter. This article looks at the differences between natural gas and renewable natural gas, considering differences in applications, production methods, advantages and challenges, current research, and future outlooks.
Natural Gas vs. Renewable Natural Gas
Typical natural gas applications include transportation, electricity, heating, cooking, producing chemicals, fertilizers and hydrogen, water heating, air conditioning, fire, and commercial applications, such as operating refrigeration and cooling equipment.
Renewable natural gas applications are relatively similar; it is often used for electricity, heating, and cooking. It is also used as a vehicle fuel and for creating bioplastics.
One of the main differences between natural and renewable natural gas is their production methods. Natural gas occurs naturally, often as methane. It is formed when natural plant and animal matter are exposed to heat and pressure under the Earth’s surface over millions of years. To access it, the Earth must be drilled onshore or offshore.
Renewable natural gas does not access these wells of gas stored underground. Instead, it utilizes renewable sources of natural gas such as landfills, animal manure, wastewater sludge, and food waste.
Around 90% of renewable natural gas is produced from landfills. Bacteria in these sources break down organic matter, converting it into gases such as methane, carbon dioxide, and other compounds. The biogas produced by this anaerobic digestion of organic matter is further processed to remove impurities.
It is common for landfills to have mechanisms of methane collection on site to take advantage of the natural methane production of these areas. In recent years, other sources of natural gas, such as animal manure and food waste, have grown in popularity. However, they often require additional policy support to set up.
Natural gas is domestically available, has an established distribution network, and is relatively low cost.
Renewable natural gas, on the other hand, has objectively more benefits. Compared with natural gas, renewable natural gas has very low levels of hydrocarbons, such as ethane, propane, butane, and pentane.
Switching natural gas with renewable natural gas can benefit local air quality by reducing particulate matter emissions and nitrogen oxides.
Using renewable natural gas instead of natural gas also reduces greenhouse gas emissions. Renewable natural gas projects have been designed to capture and recover methane produced on-site. This is vital to reducing the impact of global warming as methane has a global warming potential 28-fold that of carbon dioxide. Therefore, removing it from the atmosphere could help mitigate global climate change.
Renewable natural gas also offers benefits to the economy. Renewable natural gas projects can benefit the local economy by developing infrastructure and selling natural gas-powered vehicles. Finally, establishing renewable natural gas projects increases domestic fuel diversity, helping protect against potential disruption to energy sources.
The emissions generated from natural gas consumption are the biggest drawback of using this fuel type. Natural gas consumption accounts for around 80% of direct fossil fuel carbon dioxide emissions in the residential and commercial sectors.
Another significant challenge facing the use of natural gas is the pollution and disruption caused by drilling activities. Natural gas projects are well-known for contributing to air pollution and disturbing wildlife and water sources.
Renewable natural gas also faces barriers. However, they are less significant than natural gas. There are several barriers to production, such as up-front costs, feedstock availability, and operational and market risks.
Recent research into natural gas has often revolved around how to mitigate the emissions produced by the sector. If effective strategies cannot be widely implemented in a relatively short time frame, it will likely harm the future of the natural gas sector.
Other recent research into natural gas has highlighted the dangers of its use in home environments. One study revealed that homes in Boston, Massachusetts, relying on natural gas to power appliances had varying levels of volatile organic chemicals linked with cancer.
Research into renewable natural gas has recently revealed that production is not always carbon neutral or negative, which has flagged another barrier to the widespread adoption of the fuel. Given that lower emissions are considered a benefit of natural gas, production must be carbon neutral or negative for it to succeed. This research suggests that more development of natural gas production processes is required to ensure that they are carbon neutral or negative.
Looking to the Future of Renewable Natural Gas Use
In the future, society will likely rely less on natural gas and lean more toward renewable natural gas. Naturally, we must move toward energy sources that are kinder to the environment. However, the barriers discussed here must be overcome for renewable natural gas to meet its full potential.
Continue Reading: What is Renewable Natural Gas?
References and Further Reading
Michanowicz, D.R. et al. (2022) Home is where the pipeline ends: Characterization of volatile organic compounds present in natural gas at the point of the residential end user. Environmental Science & Technology, 56(14), pp. 10258–10268. Available at: https://doi.org/10.1021/acs.est.1c08298
Rai, S. et al. (2022) Comparative life cycle evaluation of the global warming potential (GWP) impacts of renewable natural gas production pathways. Environmental Science & Technology, 56(12), pp. 8581–8589. Available at: https://doi.org/10.1021/acs.est.2c00093
Renewable Natural Gas [online]. United States Environmental Protection Agency. Available at: https://www.epa.gov/lmop/renewable-natural-gas. (Accessed May 2023)
The Future of Natural Gas [online]. MIT. Available at: https://energy.mit.edu/wp-content/uploads/2011/06/MITEI-The-Future-of-Natural-Gas.pdf (Accessed May 2023)
Tom Cyrs and John Feldmann. (2021). 7 things to know about renewable natural gas [online]. GreenBiz. Available at: https://www.greenbiz.com/article/7-things-know-about-renewable-natural-gas (Accessed May 2023)