Environment

 

This green energy is actually beneficial to the environment- unlike most other green fuels.  The first benefit is that it helps stop pollution in areas around the farm.  Traditionally, farmers would flush all of the manure in to a pit or lagoon close to the farm to be stored. But, when there was a heavy rainfall or flooding the lagoon overflows and the waste spreads, polluting the area around it.  This means that the ecosystems around the farm were being destroyed because of the pollution, killing off species and reducing the biodiversity of that area.  With the anaerobic digester being installed there would be no concern of pollution in surrounding areas so the ecosystems could continue to thrive.

 

 

 

These pictures show the overflow of a manure pit being released into open water and a different lagoon overflowing onto the surrounding area. 

 

An anaerobic digester also decreases greenhouse gas emissions in two ways. Firstly, the factories generating electricity from coal, nuclear, etc. would not have to produce as much energy, reducing the greenhouse gases that those factories emit into the atmosphere.  The other way that greenhouse gas emissions would be reduced is by trapping the methane that would normally be released into the atmosphere.  Methane is second only to carbon dioxide in the list of greenhouse gases.  It’s 21 times more potent than carbon dioxide, meaning that it’s 21 times better at trapping heat into the atmosphere than CO_2.

 Another environmental benefit of having an anaerobic digester is the result of lower odour emissions (it’s a benefit to humans too!).  When the manure is stored in a lagoon, malodorous compounds such as hydrogen sulfide and ammonia are released.  By having an anaerobic digester the air smells better and we can all breathe healthier!

 There happens to be a negative impact on the environment from the liquid effluent that comes out of the digester, which is used as the fertilizer. In it, there is high ammonia content because it is a necessary nutrient for many of the organisms in the digester. When the fertilizer is spread on to the field, the ammonia is released and if too much is breathed in, it can become toxic. Ammonia emissions are also responsible for atmospheric acidification and fragile ecosystems, but also can have a health impact on humans and animals.