One of the newest resources to be introduced to the Renewable Natural Gas (RNG) industry is biogas. Although there are obvious benefits to biogas, there are still relatively few operating systems taking advantage of this energy, with only 2,200 systems currently active in the United States. This is estimated to be only 20% of the total market potential.
To expand the benefits and end uses of this renewable energy source, it is essential to start by understanding the basics of what biogas is, and how it actually works.
What is Biogas?
Biogas is made up of numerous different compounds, but mostly methane and carbon dioxide. It may also include small amounts of moisture, siloxanes, and hydrogen sulfide. Generally, it is produced by organic materials and then broken down by anaerobic digestion (bacteria in an oxygen-free environment). Biogas systems allow organic materials to be recycled by removing the carbon dioxide and turning the organic materials into biomethane: a type of renewable natural gas.
The process of anaerobic digestion happens frequently in our world—usually in places like landfills and livestock manure management systems. Yet, many are not taking advantage of this type of renewable gas. Only a few companies, such as Greenlane Renewables, are starting to capture the potential of biogas and put it to use in our everyday life.
What Are the Best Sources for Biogas?
There are five major sources that produce biogas:
- Food Waste: Each year, 30% of the global food supply is wasted. In the United States alone, it could be 80 billion pounds, or up to 40% of the US food supply. While it does take up the most space of any other component in a landfill, not all landfills take advantage of biogas-related technology. In a small scale example: with just 100 tons of food waste per day, anaerobic digestion is capable of powering up to 1,400 homes in a year.
- Landfill Gas: As mentioned, not all landfills use biogas-related technology, even though landfills are the 3rd largest source when it comes to human-related methane emissions in the United States. Instead of letting that energy go to waste, landfills can use water-wash technology or Pressure Swing Absorption (PSA) to separate the methane from the carbon dioxide.
- Leftover Crops: Not all parts of a crop are used during harvest: stalks, plant trimmings, straw, or similar residues are often left over. There are 104 million tons of crop residues that can be put to good use, but generally these have to be co-digested with other products as they can be difficult to break down.
- Livestock Waste: Manure is not wasted on a farm, but it can be put to further use. In a day, a single dairy cow can produce 80 pounds of manure. When this manure is used to fertilize fields, it produces methane as it decomposes (10% of all methane emissions in the U.S.), and adds excess nutrients into the waterways. However, only 3% of livestock waste is actually recycled as biogas. Taking advantage of this source could generate over 13 million megawatt hours of energy in a year.
- Wastewater Treatment: Wastewater is already being recycled for a number of uses (some are even using it to craft beer!), but many treatment plants don’t have the technology needed to capture the biogas produced. If all treatment plants used the proper equipment, carbon dioxide emissions would be reduced by 2.3 million metric tons.
The Benefits and End-Uses of Biogas
There are a number of benefits and end-uses of biogas that can’t be understated. Some of the possibilities include:
- Providing a cleaner and more reliable source of energy: even with no processing, biogas can be used for heating.
- Reducing the reliance on fossil fuels.
- Reducing greenhouse gas emissions, bettering the environment.
- Lowering costs of waste remediation.
- Lowering odors and pollution risks from livestock waste: nitrous oxide is a byproduct of manure and an aggressive greenhouse gas.
- Integration into the existing natural gas grid as an RNG: it has the potential to replace about 10% of natural gas in the United States alone.
- Powering vehicle transportation: it’s already being used in countries like Germany, Sweden, and Switzerland, including the Biogaståget Amanda in Sweden.
The Documentation Needs of a Growing Industry
Renewable energy sources are quickly becoming more commonplace in our world. As a result of this shifting paradigm, technology and companies in the industry can find it tough to keep up. Technical documentation is essential in growing industries such as biogas and we, at Shea, are here to assist in creating the necessary documentation.
Manuals, work instructions, and guidelines are needed to ensure equipment is used properly, processes are outlined to avoid mistakes, and the best practices are always recommended. It also helps employees and entire companies keep in line with any federal or local legislation, respond to updated regulations, and plan in case of emergencies. Since biogas is an up-and-coming industry, regulation across the world may change quickly, and documentation can help you keep up.
Many companies and countries are only just now starting to see the potential of RNG, so there are plenty of opportunities for biogas when it comes to energy usage in the United States and around the globe. It will be exciting to see what the future holds for the industry!