Bioenergy

Bioenergy is the general term for energy derived from materials such as wood, straw or animal wastes, which were living matter relatively recently. Such materials can be burned direclty to produce heat or power, can be used to raise steam to drive engines and turbines which are coupled to generators producing electricity, can also be converted into biofuels, can be transformed to biogas by anaerobic digestion and the biogas can be used to fuel a gas engine or gas turbine, and finally can be burned in a boiler to provide heat or to raise steam.

Biomass

Biomass is a biological material derived from living, or recently living organisms, such as wood, waste, and alcohol fuels. Biomass is commonly plant matter grown to generate electricity or produce heat.

There are many types of plants and several ways they can be used for energy production. In general there are two approaches: growing plants specifically for energy use, and using the residues from plants that are used for other things.

Biogas

Biogas plant process is based on anaerobic digestion that is a biological process that happens in enclosed digestors when bacteria break down organic matter in the absence of oxygen.

A biogas plant produces two outputs, biogas and digestate. Biogas is a mixture of gases, it consist of 50 to 70 % methane and 30-50 % carbon dioxide and trace gases such as nitrogen, ammonia and hydrogen sulphide. And digestate can be used as a fertilizer and it depends on the input material.

Biofuel

Biofuels are produced from living organisms or from metabolic by-products (organic or food waste products). In order to be considered a biofuel the fuel must contain over 80 percent renewable materials. It is originally derived from the photosynthesis process and can therefore often be referred to as a solar energy source.

Biofuels are available in three forms:

• Biodiesel made from pure plantoil, recovered vegetable oil or tallow and typically blended with diesel in a 5% mix,
• Bioethanol made from sugar beet, wheat, whey or other crops and blended with petrol in a 5% mix or in an 85% mix for use inflexible fuel vehicles.
• Pure plant oil, which is not blended and requires modification of most vehicleengines before use.

Advantages and disadvantages bioenergy

Advantages:

1. Biomass used as a fuel reduces need for fossil fuels for the production of heat, steam, and electricity for residential, industrial and agricultural use.
2. Biomass is always available and can be produced as a renewable resource.
3. Biomass fuel from agriculture wastes maybe a secondary product that adds value to agricultural crop.
4. Growing Biomass crops produce oxygen and use up carbon dioxide.
5. The use of waste materials reduce landfill disposal and makes more space for everything else.
6. Carbon Dioxide which is released when Biomass fuel is burned is taken in by plants.
7. Less money spent on foreign oil.

Disadvantages:

1. Agricultural wastes will not be available if the basic crop is no longer grown.
2. Additional work is needed in areas such as harvesting methods.
3. Land used for energy crops maybe in demand for other purposes, such as faming, conservation, housing, resort or agricultural use.
4. Some Biomass conversion projects are from animal wastes and are relatively small and therefore are limited.
5. Research is needed to reduce the costs of production of Biomass based fuels.
6. Is in some cases is a major cause of pollution.