A green future with biogas

Biogas is the very definition of a circular economy.

When we process food waste, manure and industrial waste through a biogas plant, we get green, CO2-neutral biogas.

 

  • This green gas can be used to heat homes and supply energy to businesses.

  • Green gas makes your pork chops and cheese sandwiches environmentally friendly.

  • Green gas can make your bus journeys and flights CO2-neutral. 

Not only that, but it also gives us green organic fertiliser that is CO2-neutral and contains less methane than raw manure. Unlike mineral fertiliser, this green organic fertiliser contains carbon, which is essential for soil fertility. Green fertiliser is essential for the growing production of organic crops, which biogas production can help to secure.

Biogas can even be stored and saved for a rainy day when there is neither sunshine nor wind. Green gas is also the most effective way to store green power when production is high and demand is low.

 

How biogas is produced

There are millions of domestic animals in Denmark producing enormous quantities of manure, which is one of the raw materials Nature Energy uses to make biogas. Most of the biomass used in biogas plants is manure from farm animals.  Biogas is also made using residual waste from industrial food production, food waste from households and restaurants, discarded food from supermarkets, leaves of root vegetables and energy crops such as maize.

The organic waste is brought to the biogas plant and then sent on to the plant’s processing tanks (digesters). In the digester, which run at ca. 50 °C, bacteria convert biomasses into biogas and liquid fertiliser (digestate). Before the gas is sent to the natural gas grid, CO2 and the unpleasant toxic hydrogen sulphide is removed from the raw biogas. This is done in an upgrading unit. The gas can then be distributed as green energy throughout the country. 

 

Good manure is returned to farmers

Once the manure has been digested, it is sent back to farmers, who use it to fertilise their fields. This has several advantages compared to raw manure and landfill waste. The digestate will no longer produce methane, which is a potent greenhouse gas and harmful to the environment. The fertilizer value in digestate is better than in raw manure/waste, because the nutrients are more available to plants after digestion. The high process temperature is lethal to bacteria causing diseases like salmonella. A final key benefit for everyone is that digestate is significantly less smelly than untreated manure and landfills.