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Bioenergy. Santino Di Berardino. Energy and civilization. The availability of energy has been the key to the evolution of modern civilization. It may be the key to your survival.
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Bioenergy Santino Di Berardino
Energy and civilization • The availability of energy has been the key to the evolution of modern civilization. It may be the key to your survival. • On average, each human being, out of the 6 billion people in the world, consumes two tons of coal for energy production. • There is a big difference between industrialized and developing countries. One European consumes more than six tonnes of coal, which is 40 times more expensive, than the consumption of a human being in Bangladesh. • Today, 90 percent of the energy sources used are of fossil origin and their use is associated with dioxide emissions into the atmosphere. Thus, annually, the terrestrial atmosphere receives more than 15 billion tons of CO2, which implies irreversible damages in the climate. However, meeting the energy needs of civilization need not be based on fossil energy sources.
Energy Consumption in the world Energia da biomassa
Why do we need bioenergy? • Energy is needed every where and makes our lives pleasant, whether in the form of heating, electricity or fuel. • Generally speaking, the higher a country’s standard of living, the more energy it consumes. • Water, wind and wood supplied the energy necessary for industrialisationto take place in the 18th century. These renewable energy sources were quickly replaced in the 19th century by coal, oil and gas. • Today, approximately 90 % of energy used worldwide is produced from fossil resources. This diminish coal and oil reserves and also has consequences for the climate and for the environment. • Producing energy from fossil raw materials releases large quantities of carbon dioxide (CO2) into the atmosphere in a short time, exacerbating the greenhouse effect. • Converting wood, residues or energy crops into energy, they only produce about as much CO2 as they had previously fixed during their growth. There is therefore a closed carbon cycle.
Consume of energy varies WITH Life standard • Energy consume and Life standard (PIB).
Future of Energy supply • Meeting the energy needs of civilization need not be based on fossil energy sources.
Biomass for bioenergy The following materials can be used in the generation of bioenergy: • Wood and wood waste; • The organic part of municipal and industrial solid waste; • Sewage; • Manure and agro-industrial effluents; • Crop plants and plant by-products for food production. • woody biomass, directly combusted to generate heat and/or electricity. Energia da biomassa
Conventional and alternative energy sources The conventional sources are: Fossil and nuclear energies. Alternative sources are natural resourse with ciclic or etern properties, constant and not limited- utilizam recursos naturais Eolic Energy, geothermic, solar hidraulic, wawes, tidal and biomass energy.
EU potential • 182 Mtoe can be obtained from the biomass grown on 20% of arable land in the EU-27. • This corresponds to more than 10% of primary energy demand in 2020, • Equivalent to 50-60% of the share of renewable energy
Energy potential of agricultural waste in EU-27 Heat of combustion of methane: 40.3 MJ / m3; 1 Mtoe = 44.8 PJ Assumed methane content in biogas: 65%
Bioenergy utilization chain The figure describes the bioenergy utilisation chain from sources of biomass, to biofuel production to final use of bioenergy (CEN/TS 14588). Energia da biomassa
Energy from biomass • It is the solar energy fixed by the photosynthetic process and accumulated in the organic molecules derived. • . • This energy is released in oxidation processes (reactions that degrade the biological molecules) giving as final products CO2 and H2O. Mat. Org. + O2 = CO2+H2O • Energy can be obtained by direct processes or by derived compounds (fuels) that yield their energy in the oxidation processes.
Oxidation-reduction reactions • Oxidation and reduction are complementary chemical processes, known as redox reactions involving the loss of electrons by one of the reactants (oxidation) and the corresponding gain of electrons by another reactant (reduction). • The chemical species that loses electrons is oxidized and acts as a reducing agent (donor electrons) and the chemical species that accepts electrons is reduced and acts as an oxidizing agent (electron acceptor).
Example • CO2(g)+H2(g)→2CO(g)+H2O(g) The hydrogen gas is being oxidized (reductant), an overall loss of electrons for the resulting molecule. Similarly, we expect to see a gain in the overall number of electrons for the resulting molecule of the oxidant (CO2).
Example • REDUCTION Photosinthesis 6CO2+6H2O→C6H12O6 +6O2The light-driven reduction of CO2 • OXIDATION • C6H12O6+ O2→ 6CO2 + 6H2O +EnergyEnergy-yielding oxidation of glucose reaction
Example • Some common oxidation processes are the oxidation of metals (which includes the formation of "rust" or iron oxide) and combustion. • Fluorine is the strongest oxidant. • common oxidizing agents are hydrogen peroxide (hydrogen peroxide) and the hypochlorite ions contained in the liquids. • When a car is started the oxidation or explosion of gasoline that provides energy occurs. • Biomass burning is an oxidation-reduction reaction
Oxidation in biological Processes • All living things depend on oxidation-reduction reactions to stay alive and to obtain the energy necessary for the body's metabolism. • When we breathe it is introduced into the lungs the oxygen necessary for the oxidation and energy supply to the cells • In the synthesis of energy-rich compounds, photosynthesis and cellular respiration, a complex set of reactions takes place involving the transfer of electrons between various intermediates, which alternate between an oxidized form and a reduced form.
Oxidation in biological Processes -2 • This electron transport chain ends up in oxygen (in an environment exposed to this compound), which is of great importance as the final acceptor of electrons • In the case of anaerobic microorganisms, it ends in the sulfur or other compounds that take the role of O2, forming H2. • In anaerobic digestion oxidation is partial the available oxidant is Hydrogen and Methane is formed.
Energy transfer between trophic levels It is estimated that only about 10% of available energy at a trophic level is used by the following trophic level: Energy available at each trophic level is reduced at 10 % meaning that are not possible more than 5 links in a food chain
Energy Flow Diagram Cada nível Trófico incorpora 10 % da energia do nível precedente
Tipe of biomass • Liquid • Sólid • Gas
Biomass for energy • Biomass is the oldest form of supplying energy to mankind. Modern sources of bioenergy, such as briquettes, pellets or wood chips, wood trunks, wood gas, biogas and vegetable oil or biodiesel, offer a high potential for the use of innovative energies. • These natural fuels can be used in stationary applications to supply heat and energy to homes, public buildings, agriculture and industry. The biodiesel, generated from harvests for energetic purposes, can be used in motors for motor vehicles, for which only minor modifications
Biomassa - bioenergy • The use of biomass as a renewable fuel can reduce the ecological footprint of all nations with regard to energy, • It may be the solution for minimizing climate change and other environmental problems. • The energy from biomass sources is considered to be neutral in terms of climate damage due to the greenhouse effect, because although the energy stored in the biomass emits greenhouse gases such as carbon dioxide, the amount released is the same which was consumed during the process of photosynthesis. • In contrast to the direct use of solar or wind energy, biomass as a carrier of renewable energy is available and can replace the various forms of energy (electricity, heat, and fuel) produced by fossil sources.
Biogas-Biofuels Definitions • Since the organic plant matter has absorbed carbon dioxide as it grows, when it is finally burnt to generate bioenergy it releases a comparable amount of carbon back into the atmosphere. • Agricultural biofuel production is in potential competition with agricultural food production. Bioenergy crop production is rapidly increasing in the EU, and in 2011 used 13% of Europe’s agricultural land. The land demand of bioenergy crops can be contentious and needs to be balanced in the context of an overall sustainable approach to land management. Energia da biomassa
Biogas-Biofuels Definitions • Biofuels means fuels produced directly or indirectly from biomass and bioenergy denotes energy form biofuels • Biogas, primarily methane and carbon dioxide, is produced through the bacterial decomposition of organic matter. • Biofuels are liquid fuels from a non-fossil biological origin and also represent a renewable energy resource. • Biofuels can be divided into biogasoline and biodiesel depending on the material of origin used. Energia da biomassa
Biomass - bioenergy • Biomass is the only renewable energy that can be converted into gaseous, liquid or solid fuels by means of known conversion technologies. It can be used in a wide range of applications in the energy sector. • At present it is possible to provide biomass energy for the full range of energy applications, from heating structures to supplying transport fuels. • The range of possible uses of biomass, the advantages of safe and harmless storage, and the possibility of integrating local fuel suppliers, namely agricultural and forestry companies, offer a wide range of sustainable applications.
Type and sources of Biomass uma extensa categoria de materiais:
Bioenergyproduction • About 14% of the world's energy is currently derived from biomass, equivalent to 25 million barrels a day, mostly (two thirds), produced and used in the underdeveloped countries, being the largest source of primary energy. On the other hand, biomass supplies about 35% of the energy needs of developing countries. • In developed countries, the weight of biomass energy is reduced to only 3% of national energy consumption. It is necessary to deal with and work with biomass more efficiently, to plan more advantageous forms of primary production and to evolve in the area of conversion and exploitation of primary biomass in chemicals and fuels. • The reorganization of the world's territory with a view to encouraging the production of biomass enables it to combat a number of environmental degradation phenomena such as climate change, greenhouse effect, erosion, desertification, deforestation, etc. • The annual production of biomass via photosynthesis corresponds to eight times the total world energy consumption, there being a potential that can be valued and managed in a way that can support the development of humanity.
Bioenergy perspectives • The Earth's atmosphere receives more than 15 billion tons of CO2 per year, derived from fossil energy, with irreversible damages to the climate. • CO2-neutral energy resources, such as the direct use of solar energy, wind energy and the indirect use of solar radiation in the form of biomass, can provide the necessary energy. • In the White Paper of the European Union the following targets for the use of biomass in the year 2010 are established for the member states: • 5 million tons of biofuels;10000 MW of biomass in cogeneration plants;1 million households provided with biocalor;1 million jobs in the bioenergy sector.
Biomass potential - economic and social aspects • Creation of jobs resulting from the harvesting, treatment and transport of biomass. • In the long term, for every Gigawat-hour generated, bioenergy could generate 1.75 new jobs. • Biomass offers considerable potential to support sustainable structural development and to strengthen rural areas in Europe. • Bioenergy sources have long-term advantages for rural development, but also for agricultural food production. • Biomass as stored solar energy is an element for a sustainable economic policy.
Technologies for energy from Biomass Thermochemical Methods: Are based on thermochemical reactions that transform matter into energy. Cellulosic products with a C / N ratio of more than 30 and a moisture content of less than 30%. Biochemical Methods: They are based on chemical reactions of biological agents (enzymes, microorganisms, fungi). Biomass with a C / N ratio of less than 30, and humidity greater than 30%.
Fermentation Biological Process that allows to synthesize several compounds from the glucose, by means of microorganisms such as fungi, yeast bacteria etc. (ferments)
The Market • Biomass contributes significantly to sustainable energy supply in a number of European countries. • In the European Union, more than 2200 petajoule of energy per year, stored in the form of biomass, are being produced. Of these, about 1700 Petajoule are used directly to generate heat, while the remaining 500 Petajoule are used to generate electricity. • In addition, the European Union has set an average energy value of 12% for renewable energy resources for the year 2010 and for the energy sector. Biomass is expected to provide 10% of all energy in Europe, ie an amount equivalent to about 5800 Petajoule. • At present, some EU member states follow this objective. Finland, followed by Sweden, supply more than 10% of the energy needed through biomass. These countries use almost half of their biomass potential, proving that a consistent development in the bioenergy sector can be successful.
Share of renewable energy in EU Energia da biomassa
Quota de bioenergia comparada com o consumo total de energia
Energy needs Electric Energy Natural Gas Liquid fuels
Biofuel - Concept • Energy product of biological origin • May be Solid, liquid or gaseous • It is applied to generate heat, electricity or transport (biofuel) • It originates from living matter • It has different time scale and spare speed in relation to fossil fuels. • Fuel derived from biomass is renewable
