How to Convert Organic Waste into Electricity

Transforming organic waste into electricity is not a recent idea, but it is one that is gaining more traction as renewable energy sources are sought after and implemented. There are two primary means of converting organic waste into electricity: biogas production and WtE or waste-to-energy production. In both cases, the scale required is vastly larger than can be accomplished at the individual level. The processes involved require heavy capital investment and somewhat complex industrial capability. There is a relatively simple method for the production of biogas on an individual scale, but it requires optimal temperatures for fermentation as well as methane-rich livestock manure. Producing gas at home, it can then be combusted and used to produce electricity. While theorized for implementation in third world countries, it has ramifications for the industrial world as well. 

Step 1: Organic Waste Drains to Digester

The first step in the process of turning organic waste into electricity involves the draining of organic waste into the underground digester. What drains includes waste from toilet facilities and garbage disposals. Livestock manure is added as well. 

Step 2: Waste Releases Methane Gas

Through an anaerobic process, that is, in the total absence of oxygen, the waste is broken down or digested in the digester. This process of energy recovery releases methane gas. In other words, potential energy stored in the organic waste is harnessed. The byproduct of this process is an organic fertilizer that flows through an outlet valve. This fertilizer can then be used to aid in the growing of crops. 

Step 3: Biogas Pumped through Gas Valve

Once the biogas is released from the organic waste, it is then channeled through a valve. This is where its use becomes evident. It is useful as is for cooking energy and gas heat, but it can also be converted to electricity by combusting it. 

Step 4: Combustion of Biogas 

The combustion of the biogas can heat water in a boiler which then moves turbines to generate electricity. Once the electricity is converted into a usable form, it will provide a home or community with electrical power. 

Organic waste such as livestock manure is incredibly rich in methane. This makes it the ideal ingredient in the process of creating biogas and recovering useful energy. While small scale biogas plants are possible, the organic waste inputs required to make them a viable means of energy production are larger than a single home can provide. Communal biogas plants are conceivable, especially where there is a constant population of livestock producing large amounts of organic waste. Energy recovery is made easier when the average temperatures are in the subtropical range. This is one reason why this technology has been implemented in Africa and parts of Asia. In order for it to work in generally cooler climates, adjustments would have to be made. Cost is not prohibitive for small scale, domestic biogas plants provided the temperature is suitable for waste fermentation and there is a minimum supply livestock manure.