Biogas is a renewable energy (RenEn), like hydro, solar, and wind part of any RenEn portfolio.
The biogas technology is proven, secure, feasible and sustainable. Biogas production units work without noise, emissions or odors. There are about 15,000 biogas installations all over Europe, situated next to farms and stables, industrial, and residential areas. Several million traditional small household-scale fermenters can be found in India and China. Biogas has a huge potential, especially in Africa.
The central idea of biogas is as intuitive as simple: use waste to produce cheap, green, CO2-neutral, non-fossil, decentralized, off-grid energy. At the same time, address the ever increasing environmental waste challenges.
In an anaerobic digestion (AD) process we use biological, degradable, organic waste as energy-producing matter, called the entrants, substrates or in-lays – such as
- Cattle and poultry manure,
- Slaughterhouse waste,
- Fruit and vegetable residues,
- Cereal and corn residues (like husk, stalks) ensilage,
- Agro-industry residues like milk serums, molasses, wastes from olive and palm oil production, from breweries and wineries,
- Organic fraction from municipal waste streams, restaurant and hotels,
- Sludge from wastewater treatment plants etc.
- Algae, in the future.
We use waste, not food!
from organic matter to biogas.
Organic matter consists of CHNOPS (45-55% carbon, 35-45% oxygen, 3-5% hydrogen, 1-4% nitrogen, phosphorus, sulfur). In an anaerobic digestion process – oxidation in the absence of air -, organic matter is degraded by natural bacteria. The product of this process is called biogas; it consists mainly of methane (CH4, ca. 60%) and carbon dioxide (CO2, ca. 35%), and others (H2O, NH4, HS2, H2,…).
Anaerobic digestion is essentially what happens in the stomach of any ruminant. The anaerobic digestion process produces no heat. please read anaerobic digestion.
energy. output is flexible.
The produced biogas can be used in various ways:
- Co-generation: producing electricity and heat in roughly equal amounts, also called combined heat and power (CHP),
- Tri-generation: producing electricity, heat, and cold,
- To gas-fire boilers or burners directly,
- After purification: as a vehicle fuel for natural gas adapted vehicles,
- After purification: injected into a gas network.
pls. see energy.
Biogas plants may work parallel to the grid, inject to the grid or as island solutions, off-grid, decentralized, they are as direct replacements to fossil fuels. Biogas is produced continuously, 24/7, 365 days a year; it is storable and transportable. The energy production is flexible and adapts to client needs.
The residue of the anaerobic digestion, the digestate, is rich in nutrients (nitrogen N, phosphorus P and potassium K, and others), and shall be used as natural organic fertilizer to improve soil in agriculture, as a direct replacement of industrial fertilizers.
pls. read more circular economy.