Renewable Natural Gas
Dairy Farms
Renewable Natural Gas Solutions for Dairy Farms
Bringing waste-to-energy solutions that bring additional revenue stream opportunities to dairy farmers.
What Is Dairy RNG?
Dairy RNG refers to renewable natural gas, also called biomethane, that’s sourced from dairy farms. It’s a renewable energy source created by capturing methane from dairy farm manure. It involves processing that removes impurities and upgrades the gas into a clean fuel that’s interchangeable with fossil natural gas.* The resulting gas can be used for vehicles, heating, or electricity. The process turns farm waste into a valuable revenue stream and helps reduce greenhouse gas emissions.
SJI Renewable Energy Ventures has an established portfolio of projects with dairy farm owners and operators that spans across the U.S.
How Do Dairy Farms Produce Renewable Natural Gas?
RNG is derived from naturally occurring gas that emanates from the decomposition of organic waste. This includes food waste, garden and lawn clippings, landfills, municipal wastewater, and dairy waste, namely cow manure and unused or unsuitable cattle feed.
Capturing RNG is a process that begins with collecting manure and loading it into an anaerobic digester, where microbes break it down. In this oxygen-free environment, microbial colonies digest the waste. This process of anaerobic digestion produces a biogas that’s the source of the desired RNG.
This biogas comprises methane, carbon dioxide, and a small amount of other gases. By cleaning and processing this gas, many of the non-methane components are stripped away. This leaves a purer natural gas that’s suitable for use as an energy source for electricity, heat, and specialized vehicle fuel. Pipeline-quality RNG can often use the same infrastructure as conventional natural gas.
Environmental Benefits of Dairy RNG
Some key sustainability benefits of dairy RNG include:
- Reduced carbon emissions: High-quality RNG is almost pure methane, so it’s a low-carbon fuel. Using RNG for heat or in fleet vehicles lessens the demand for carbon-intensive fuels, such as gasoline or diesel.
- Stable methane emissions: RNG is synthesized from naturally occurring methane. This methane would eventually escape from the dairy cow manure (or other source). Using it for fuel doesn’t add to methane emissions.
- Waste removal: An RNG facility can help with waste cleanup, as opposed to letting the waste products sit unused. For dairies, RNG projects provide a place to deposit manure.
- Remaining fertilizer: A dairy farmer can still use the manure for fertilizer. The anaerobic digester separates the organic matter into biogas and solid and liquid digestate, and this can be used for fertilizing soil.
Economic Value and Revenue Opportunities
- Additional revenue: RNG projects provide additional revenue streams for dairy farmers.
- Waste monetization: RNG is derived from waste, turning a byproduct into a valuable commodity.
- Energy cost stability: RNG can provide cost-effective emissions reductions, bringing down energy costs.*
- Leveraging existing assets: RNG can use existing natural gas pipelines, reducing the need for new infrastructure.**
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Project Development and Implementation Process
A typical RNG project lifecycle develops over the following phases:
1. Consultation to determine the viability of the location.
2. Installation of the digester and other necessary equipment on or near the farm.
3. Manure collection.
4. Anaerobic digestion.
5. Biogas treatment to remove contaminants.
6. Injection into gas pipelines, sometimes requiring permits and utility agreements.
FAQs About Dairy RNG
Here are some frequently asked questions about renewable natural gas sourcing from dairy farms:
How Is Renewable Natural Gas Produced From Dairy Farms?
Dairy RNG is produced by capturing the methane emitted from decomposing manure in a sealed digester. The resulting raw biogas is then “scrubbed” to remove impurities and carbon dioxide, leaving behind pipeline-quality methane.
What Are the Benefits of RNG for Dairy Operations?
A dairy RNG project can transform waste into revenue through gas sales and, in some cases, environmental credits.
How Do Anaerobic Digesters Support Dairy RNG Projects?
The digester provides an oxygen-free environment where bacteria break down organic matter to release methane. Without the digester, this methane would simply escape into the atmosphere.
Is Dairy RNG Economically Viable for Farmers?
Yes, because it brings value to byproducts, such as cow manure. Initial capital costs can be lessened by partnerships with developers, leading to an ongoing project where farmers are remunerated for waste products.
What Is the Difference Between RNG and Biogas?
Biogas is the raw, untreated gas that’s collected directly from the digester. RNG is the purified version that can be injected into commercial pipelines or used as vehicle fuel.
Is RNG the Same as Biomethane?
Yes, they are essentially the same. “Biomethane” is the technical term for the methane molecule produced from biological sources, while “RNG” is the commercial and regulatory name used in the energy industry to describe that gas once it’s been purified to meet pipeline standards.
Benefit From Dairy RNG With SJI REV
SJI Renewable Energy Ventures is turning today’s organic waste into pipeline-quality gas. Learn how we can help your business move to a more sustainable future.