Biomass Energy as a Renewable Resource
What is Biomass is it a Renewable Energy Resource
Another interesting alternative energy source that can also be classed as a “renewable energy resource” is the development of Biomass Energy and Bioenergy. Biomass energy is a term used for any kind of non-fossil fuel that is classified as being organic, biological or made of plant matter, and which can be converted into a usable energy source. Biomass is considered to be a vital resource on the earth to the point of being called a “Biorenewable Resource”.
Biomass technologies are being created that will enable living plant matter such as agricultural crops, seeds, grasses, wild plants, trees and shrubs, etc, as well as organic waste in the form of biodegradable materials, garbage, compost, animal manure and other waste products to be converted into usable energy. But what is biomass.
Biomass takes on many forms, but a good example of “biomass energy” is the open burning of dead wood, sticks or straw on a camp fire for heating and cooking. However, this type of biomass incineration is not very efficient as most of the heat energy it produces goes up with the smoke.
Through the process of photosynthesis, living plants have the capacity to capture and utilise the immense energy derived from the sun, along with carbon from the Earth’s atmosphere and nutrients absorbed from the soil to generate biomass. Then we can define biomass as being any organic or biological material which contains stored sunlight in the form of chemical energy.
The transformation of organic and biological substances, which would otherwise end up as land fill waste, into heat and electricity is an exciting area that has a great deal of potential to produce energy from previously untapped sources without directly polluting the environment.
Biomass materials produced from processing plant matter, crops, forest waste, or faecal wastes can be in solid form or, through a wide range of conversion and refining processes, made into liquids or gases which can then be used to produce electric power, heat or fuel. In addition to providing solids, fuels and gases, biomass can also be used in a majority of man-made materials, including fabrics, medicines, chemicals, and construction materials.
Biomass is organic matter just like fossil fuels (coal, oil, or natural gas), the difference is that fossil fuels were formed in the earth from plant and/or animal remains over millions of years, while biomass on the other hand is more recently created and is renewable on a much smaller time scale as plants grow continuously, animals constantly produce manure, and people throw away waste material every day. Also, using biomass materials for fuel does not deplete their supply because they are constantly being grown making biomass a renewable energy resource. For this reason, many people believe that “biobased products” including Bioenergy and Biofuels will be a major renewable energy source for the future.
Biomass as a Fuel
Until about 400 years ago when man started digging coal out of the ground, the world depended nearly exclusively on biomass and biomass type products as a source of energy. Biomass is still a major source of energy today, and in recent years, biomass energy has been gaining ground as a commercial fuel purchased as charcoal for cooking, firewood for heating, and crops grown specifically for their energy content. When used in this way, biomass materials are called “feedstock”.
Biomass is available in all three basic forms of matter: Solid, Liquid, and Gas, which themselves can be sub-divided into primary (produced by direct use of solar energy through photosynthesis) and secondary (generated by the decomposition or conversion of organic substances) products. The biofuels derived from these three states are defined as:
• Solid Biomass – also known as “feedstock”, which are solid or compressed pieces of organic matter in the form of pellets that release their stored energy through combustion and burning. Solid biomass or feedstock materials include:
- Wood & wood residues such as trees, shrubs, sawdust, pellets, chips and waste wood.
- Agricultural residues like straw, grasses, seeds, roots, dried plants, nut shells and husks.
- Energy crops from charcoal, peat leaf litter and moss.
- Processed waste such as Bagasse plant waste.
- Animal waste such as dried slurry and manure.
- Municipal solid waste from household rubbish and garbage.
• Liquid Biomass – also known as “biofuel”, is any kind of fluid or liquid produced from solid matter that is still growing or has been alive at some point which can be processed to produce a type of fuel. Liquid biomass or biofuel fluids include:
- Vegetable oils either new from sunflower, rapeseed or recycled waste vegetable oils.
- Methanol, Ethanol and alcohol based fuels fermented from corn, grain and other plant matter.
- Biodiesel distilled from vegetable oils and animal fats.
- P-Series fuels, which blend various solid and liquid matters together to produce a fuel.
• Gas Biomass – also known as “biogas”, is any kind of natural forming gas given off by decaying plants, rotting rubbish, decomposing animals, slurry and manure that can be used as a type of fuel. Liquid biomass or biogas include:
- Methane from decomposing plants, animals and manure.
- Biogases generated from rotting rubbish in landfills.
- Hydrogen for batteries and fuel cells.
- Synthesis Gas blended from Carbon Monoxide and Hydrogen.
- Natural Gas from fossil fuels.
There are four principal ways in which organic materials and crops can be used as a biomass or biofuel as part of a renewable energy resource.
• Thermal Combustion of Biomass – the burning of solid biomass materials, also called incineration, in air is the most common use of biomass fuels today. The bioenergy released from this process is used directly for space and water heating, as well as cooking and washing.
Domestic thermal combustion of solid biomass materials for cooking and space heating, may be an attractive alternative to conventional fossil fuels especially where the biofuels are available at economic prices or, particularly in isolated or rural areas, where the biofuel may be available for gathering by the consumer locally.
Small-scale use, such as for home cooking and burning in open fireplaces is usually very inefficient as most of the bioenergy goes up the chimney as wasted heat. High-efficiency cooking stoves, home heating stoves, and fireplace systems have been developed especially for biomass energy combustion and are now widely available.
Larger furnaces and boilers have also been designed for burning various types of solid biomass materials such as waste wood, wood chips, logs, sawdust and nut shells either with or without a high moisture content. The larger units can be very efficient over a wide range of particle sizes and compositions, nearly matching the performance of traditional oil or gas fired furnaces.
• Electrical Generation using Biomass – Biopower, or biomass power uses the heat and/or steam produced by burning the feedstock to generate electricity. Most electrical generating stations and conventional power stations use fossil fuels in the form of coal as their primary fuel source. Current predictions indicate that the utilisation of steam coal for power production worldwide will increase substantially over the next few decades so the market demand for a high efficiency, clean, coal-fired power generation plants is high.
By pre-mixing the coal with solid biomass feedstock, a new type of fuel can be produced for burning in existing coal-fired boilers. The mixed fuel can still be processed through the same coal handling, milling and firing systems as before, the advantage now is that the co-firing of solid biomass reduces the generating plants reliance on fossil fuels only, reducing its waste ash content and harmful sulphur and CO2 carbon emissions.
Both dedicated biomass and biomass cofiring power plants are used in the production of electricity, with large scale biomass cofiring being one of the most efficient and cost-effective approaches to generating electricity from renewable sources. The main advantage of biomass co-firing power generation plants is that Biomass is much cheaper than coal, so cofiring is cheaper than burning coal alone.
Nearly all current power generation from biomass energy uses steam turbines. The cofiring of biomass and coal to generate the required amount of steam to drive the turbines produces gases that can be captured, cleaned and used as another bioenergy product.
Biomass cofiring for electricity generation can also provide other industries such as forestry, wood products, pulp and paper, agriculture, and food processing, etc, with a way to sell their large quantities of combustible biomass residues instead of sending them to land fills. The cost of processed biomass fuels can be low when large amounts of wood and agricultural waste are available.
• Gasification of Biomass – a subsection of biomass is Biogas, which is a naturally produced gas generated from biological sources such as animal manure, rotting waste and algae. The gasification of biomass into a fuel which can then be used directly or transported by road or pipeline to the final consumer for heating or power generation, is another useful form of bioenergy.
Biogas is the biological anaerobic (bacterial decomposition without oxygen) digestion of biomass materials producing a 60/40 gaseous mixture of Methane (CH4) and Carbon Dioxide (CO2). If you’ve ever seen bubbles rising from a swampy marshy area or algae filled pond, that is naturally produced methane. The methane is separated from the carbon dioxide using conventional technology to supply gas to a natural gas system or other consumer.
Like the gas in the orange liquid petroleum gas (LPG) canisters, Biogas can be burnt in conventional ovens, stoves and boilers for cooking, heating or lighting the home. It can also be used to power internal combustion engines to drive a car or generate electricity.
Biogas energy offers many advantages over a conventional natural gas. Biogas powered electricity plants can be built quickly, simply, and for much less money per kilowatt than coal, oil, or nuclear power plants. Unlike fossil fuels, “Biogas” is a renewable resource. The methane produced by the bacteria decomposition of organic matter is still going to be naturally produced in landfills and farmlands whether it is used as a gas or not. Methane is also an important greenhouse gas and is a major contributor to the global warming problem so burning Biogas provides an excellent source of energy that is helpful to the environment. Finally, the residue left over from the burning of Biogas, called activated sludge, can be dried and used on the land as fertiliser.
• Liquid Conversion of Biomass – another exciting alternative energy is the production of biomass fuels called Biofuel. Biofuel is liquid fuel made from biomass, usually from plant matter. There are many types of biofuel with some common ones including methanol and ethanol, as well as synthetic gasoline, biodiesel, and aviation fuels.
Ethanol (ethyl alcohol) biofuel which is harvested from corn, sugar cane and soya beans, is now the most common biofuel worldwide and is generally considered to be a “renewable energy resource” because it is primarily the result of conversion of the Sun’s energy into usable energy.
Transportation also requires fuel, and ethanol can be used to run cars replacing or augmenting gasoline as a significant source of automotive fuel. Ethanol used as a fuel burns more cleanly than gasoline thereby producing fewer pollutants and emissions. Biodiesel is another type of liquid biofuel which can be used as an alternative to petroleum diesel for the internal combustion engine.
Biodiesel is an ester-based oxygenated biofuel generally made from processing vegetable oils or animal fats. However, it is common to use various percentage blends of biodiesel with a variety of plant oils such as palm oil and canola oil to increase efficiency and engine life producing a ultra-clean diesel fuel. Biodiesel has many advantages as a transport diesel and can be used in any type of diesel engine from cars to large trucks making the switch to biodiesel very easy.
Biofuels may offer many advantages over conventional carbon based oil and fuels. One big advantage of biofuel is that it is renewable. Biofuel is an exciting prospect because it will enable farmers to turn excess crops into fuel but the magnitude of these advantages depends on how a biofuel crop is grown and converted into a usable fuel. Biofuel also reduces dependence on imported oil, as much of the fuel can be produced within a country.
However, there are also many disadvantages to the production of biofuels. Fossil fuel energy must be used to produce biofuel, which makes it less efficient. Large amounts of land are needed to support the crops grown for biofuel production, decreasing the amount of land available for food production which itself could lead to other problems such as an increase in food prices and a shortage of certain food crops on the global market.
Biomass Energy Summary
Using Biomass to produce clean renewable energy can reduce our reliance on fossil fuels, reducing greenhouse gas emissions, and reducing pollution and waste management problems. Through the process of photosynthesis, plants have the capacity to capture and utilize energy, derived from the sun, along with carbon from the earth’s atmosphere and nutrients from our soils to generate biomass which can then be used as a Bioenergy through the combustion of organic materials.
Biomass has many advantages as a bioenergy fuel, reducing waste and emissions, using a variety of different crops supporting farmers, producing new cleaner and renewable alternatives to crude oil and conventional fossil fuels. But not everything associated with biomass energy is green as it too has its disadvantages.
For example, biomass is only renewable as long as it is not consumed faster than it can be replaced. Solid forms of biomass fuel have a much lower energy content than due fossil fuels. Also fossil fuels are consumed to produce bioenergy fuels and large amounts of land are required to grow the trees and crops decreasing the amount of land available for agriculture and food production.
“Biomass” and “Bioenergy” are available in the there basic forms of a solid, a liquid or a gas. Solid biomass can be used as it is found and burning biomass generates heat which can then translate into energy, but solid biomass fuels have a much lower energy content than fossil fuels. Liquid biomass in the form of biofuel is a clean renewable fuel made from waste vegetable oils, animal fats and plants. The most common biofuels are “ethanol” and “biodiesel”. Both these products can be used as an alternative to traditional transport fuels.
Biogas is a mixture of gases produced by the fermentation of waste material in anaerobic (without air) conditions. This produces various gases including methane, carbon dioxide, nitrogen and hydrogen. Because biogas contains so much methane, it can be used as an alternative energy source to natural gas for both cooking and heating.
To gain a better understanding of “Biomass and Bioenergy”, to obtain more information about the various biomass energy systems available, or to explore the advantages and disadvantages of biomass and bioenergy, then Click Here to get your copy from Amazon of one of the top “Biomass Books” today to learn more about making biomass pellets to burn in your home to save money and the environment.