Biogas Generator Turns Food Waste into Natural Gas and Fertilizer

July 20, 2018 at 6:38 pm





Invention produces homemade natural gas and fertilizer from food waste, grass clippings and livestock manure.




The HomeBiogas 2.0 converts food scraps, yard waste and livestock manure into natural gas for cooking and fertilizer.

Similar to an animal’s stomach, the biogas generator digests the organic “waste” materials and produces a natural gas in the process:

Biogas is a mixture of flammable gases (mostly methane) and carbon dioxide that forms anywhere organic material decomposes without oxygen, such as under water, deep in a landfill, or in the guts of animals, explains renewable energy consultant Paul Scheckel in an article for Mother Earth News.

Scheckel provides instructions for building your own biogas generator in his book The Homeowner’s Energy Handbook:

A simple 200 gallon tank with an inlet, two outlets, and organic “waste” material, is basically all you need to supply at least enough biogas for the average family’s cooking needs. Larger systems can be put together for meeting more energy needs including space heating, water heating or even powering a diesel or natural-gas car.

A 600-gallon biogas generator in Oregon turns 15 pounds of food waste into cooking fuel daily. Designed by Hestia Home Biogas.

“If you can compost it, a biomass generator can digest it,” Scheckel says.

Nearly any combination of vegetables, food scraps, grass clippings, animal manure, meat, slaughterhouse waste and fats will work as long as your recipe contains the correct ratio of carbon and nitrogen, he says. Just avoid using too many woody products, such as wood chips and straw, which tend to clog up the digestion process.

Once you’ve collected enough biomass, mix it with about ten times as much water and a starter culture of methane-producing organisms. (If you use manure, you won’t need microbes).

Put the slurry in an airtight container, and keep it as close to body temperature as possible by putting it in the sun or a greenhouse.

Your biogas should be ready in about a week.

Release the biogas through a pipe into an airtight storage container. Through a larger outlet will come compostable solids and nutrient-rich liquid, which make an excellent soil amendments.

For more detailed instructions, buy Scheckel’s book The Homeowner’s Energy Handbook or Biogas and You: Building a Biogas Digester at Home: