Should I produce biogas with my farm?


Biogas for farms: what does it take to become a biogas producer?

Biogas can be a great way to turn farm waste into a valuable resource. If your farm produces large amounts of animal manure and plant waste, you may want to consider installing an anaerobic biodigester to turn this waste into valuable biogas. Although most of our projects involve solar energy, we also have experience with biogas, and you can contact us to learn more about your options. Building a biogas project for your farm is not only an eco-friendly approach but can also reduce energy costs, minimize waste, and enhance your farm's sustainability.


What is biogas?

Let’s start with the basics. Biogas is a gas that consists mostly of methane and carbon dioxide, with a little bit of hydrogen sulfide, siloxane gases and water vapor. It is produced by processing organic waste and is used as fuel, just like natural gas. It is a renewable energy source, since it leads to no new carbon dioxide emissions (unlike natural gas). This is because the carbon dioxide released when the biogas is burned was captured from the atmosphere when the organic waste was produced over previous months, and has not been sequestered underground for millions of years, as is the case with fossil fuels.

Sources of biogas include processing in anaerobic digestors any of the following byproducts. The digestor converts these waste products into biogas through the help of friendly microorganisms called methanogens. Waste sources that can be used to create biogas include:

  • Agricultural waste from animals (manure)

  • Plant waste from harvesting and any organic waste that can be composted

  • Sewage

  • Municipal waste (landfill gas is produced from waste processing facilities and is almost the same as biogas)

Biogas has many uses:

  • Fuel for heating (any heater powered by natural gas)

  • Electricity production by burning biogas in engines, after purifying it. Biogas is a great fit for Combined Heat and Power

  • Injection of biogas into the natural gas grid (also requires purification to meet standards)

Biogas facilities like this one are a complex operation with a lot of equipment.

Will a biogas project work for my farm?

A biogas project is viable if several factors align. These include:

  • Sufficient waste product as a biogas feed source. The EPA recommends having at least 500 head of cattle or 2000 hogs for biogas production to be economically attractive.

  • Use case for produced biogas. You can fuel onsite boilers or gas engines to produce electricity for internal use or to sell into the grid.

  • Sufficient space on your farm to install biogas production equipment.

 

What does biogas production actually look like?

A biogas production process requires many steps:

  1. Waste source: Waste from animals is collected from where it is produced.

  2. Delivery to biodigester: Waste stream is mixed into a slurry, which is pumped into the fermentation tanks of the biodigester

  3. Conversion to biogas: in the tanks, the waste is kept under anaerobic conditions. Bacteria do the job by converting the waste into carbon dioxide and methane. Some additives may be included to reduce the amount of unwanted chemicals that are produced (such as ammonia and hydrogen sulfide)

  4. Gas collection & purification: the produced biogas is collected from the fermentation tank and purified. Greater purity is required for burning the biogas in engines, while less pure biogas can be burned in boilers. Leftover solid waste can be used as a fertilizer.

  5. Gas use: the biogas can be burned in engines for power generation, or directly in a boiler to cover the farm’s heating needs. Biogas can also be purified to a higher standard and injected into the natural gas grid.

Biogas production requires special equipment.

Biogas safety

Biogas projects convert waste into a valuable resource, but are quite complex and require high upfront investment. If operated correctly, they can be a great addition to your farming operation and have payback period of 4 – 8 years.

However, biogas projects also come with significant risks: leaks from your biogas facility can be very dangerous, aside from causing bad odors.

  • Explosion: Biogas consists most of methane, so it is explosive or at the very least, a big fire hazard, when it comes into contact with oxygen from the air.

  • Toxicity / asphyxiation: biogas often contains hydrogen sulfide, which is a poisonous gas. A biogas facility operates anaerobically, so it does not have the oxygen we need to survive. Both poisoning and asphyxiation are potential risks when entering a biodigester to conduct maintenance.

A well-run biogas facility mitigates these risks to the point where they are manageable. But if you would rather use your land for a project that doesn’t have such risks and makes more money, solar energy is a better fit since you can lease your land to a developer without any investment, and solar projects are not nearly as dangerous as biogas facilities. Contact us to learn more about your options.

A large livestock farm produces enough waste to produce biogas at a large scale – the waste pond shown here doesn’t thrill environmentalists, but at least the biogas is a renewable fuel.

If you want to look beyond farming, contact us to learn about solar and help you obtain an offer to lease your land from the developers within our network.

Tell us about your land, so that energy developers can propose a solar project on your plot. Make money from your land and make the world more sustainable.

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