Harmonizing to Key World Energy Statistics 2010 published by International Energy Agency ( IEA ) , the entire energy production increased from 6224.35 Mtoe to 12368.95 Mtoe in the period of 1973 to 2008 and the energy ingestion is about the same as the energy production. In these 30 five old ages, the energy supply had a dual growing, which means the addition of energy ingestion besides doubled. The energy ingestion in the USA by sector in 2009: Industrial sector consumed 30 % of energy, residential sector consumed 22 % of energy, transit sector consumed 29 % of energy and commercial sector consumed 19 % of energy.
Fossil fuel is the major energy beginning, which contribute about 86.9 % of energy supply in 1973. The renewable energy and atomic energy lend 13.1 % of energy production. Half of the entire energy supply comes from rough oil. In 2008, dodo fuel is still the major energy beginning in the universe, but its part decreased to 81.4 % . The part of renewable energy and atomic energy increased to 18.6 % of energy production. A one-fourth of the entire energy supply comes from rough oil. Although rough oil is still the major energy beginning presently, the extraction of rough oil is about maximized. After that the production rate will worsen, which called “ extremum of oil ” and this will likely happen in 2015. These figures show that planetary energy supply no longer merely relies on fossil fuels, the function of renewable energy in energy supply becomes more and more of import.
The tendency of renewable energy development.
Burning dodo fuel for energy supply will bring forth a batch of air pollutants, which will damage the natural environment and is risky to human wellness. It besides emits big sums of C dioxide, doing serious planetary heating, which has lead to a batch of serious natural catastrophe. On the other manus, utilizing renewable energy to supply energy causes comparatively fewer pollution jobs. Therefore, renewable energy engineering is now playing an unreplaceable function in energy supply.
In order to develop renewable energy as a dependable and sustainable energy beginning, the authorities must continuously put a billion of money to renewable energy engineering. The universe one-year investing in new renewable energy capacity can bespeak the tendency of renewable energy development.
From 2004 to 2008, the world-wide one-year investing in new renewable energy capacity has at least a 30 per centum addition. Although the investing growing rate in 2009 merely has a 15 per centum addition comparing to the figure in 2008, it does non intend that the function of renewable energy has significantly changed. The growing rate decreased because the investing base in 2008 is big but the extra investing has non increased.
All in all, the universe invests a 100 billion of US dollars in renewable energy every twelvemonth proved the importance of renewable energy.
a ) The extremum of oil production -Timings and market acknowledgment
Energy Policy, Volume 37, Issue 4, April 2009, Pages 1267-1276
Pedro de Almeida, Pedro D. Silva
hypertext transfer protocol: //www.ren21.net/globalstatusreport/g2010.asp
hypertext transfer protocol: //www.eia.doe.gov/iea/overview.html
Chapter 2 ( Page 3-5 )
Brief description of renewable energy beginnings
Renewable energy beginnings are the beginnings that can be continuously replenished by natural procedures. [ ] Generally, in the Earth all of the energy finally comes from the Sun. No affair are they bioenergy, hydro power, air current, wave, tidal, geothermic and solar energy, all of them are assorted signifiers of solar power. The abovementioned renewable energy beginnings will be briefly described as follows. [ ]
The solar energy is the hugest measures of primary energy beginning in the Earth. The Sun annually radiates energy which can make the Earth ‘s surface is about 10000 times of the world-wide current conventional fuel ingestion rate. [ ] If human can use this powerful solar energy efficaciously, solar energy can doubtless to the full fulfill the worldwide energy ingestion. Actually, human already have a long history of using solar energy. For illustration, utilizing seeable visible radiation for light. Olympic torch is kindled by the sunshine which is concentrated by a parabolic mirror. [ ] hypertext transfer protocol: //en.wikipedia.org/wiki/Olympic_Flame. Application of solar energy is referred to using solar radiation for human patterns. It can be delivered into two techniques: Active and inactive solar techniques. Passive solar energy technique uses the Sun ‘s radiation but without utilizing solar thermic aggregators and photovoltaic ( PV ) . Active solar energy technique uses the solar energy by photovoltaic panels, pumps and fans to bring forth electricity.
Passive solar construct combined with architectural design, utilizing solar energy to accomplish heating and light effects in order to cut down the electricity ingestion. Solar energy can besides be used to heat H2O for rinsing or infinite warming in edifices. [ ]
Solar energy can be harnessed for generate electricity straight by utilizing solar photovoltaic, which are made of particular beds of semi-conducting stuffs ( such as monocrystalline Si ) . The solar cell can change over the Sun radiation to electricity. Electrons are emitted from semi-conducting stuffs when specific energy of photons radiances on monocrystalline Si.
Solar energy can besides be transferred to electricity by utilizing arrays of concentrating mirror to concentrate Sun ‘s beams which are strong plenty to zap the H2O to high temperature steam. The steam can drives turbine to bring forth electricity.
Wind energy is an indirect usage of solar energy because solar radiation enters the Earth ‘s ambiance. Solar radiation heats up the air in different extents, leads to temperature and denseness gradient. The air in heater parts ( equator ) tends to flux toward the ice chest parts, that is the formation of air current.
Wind power has been used in traditional windmills for crunching maize or pumping H2O for centuries. Nowadays, air current power has been used in bring forthing electricity. When the air current flow through air current turbines, it drives the turbines and the generator rotates, electricity therefore produced. The installing of air current turbines are non limited on the land, it can besides be installed in the sea so as to cut down land usage for electricity coevals.
When the air current circulates on the sea, it will upset the oceans, doing moving ridges. The moving ridge energy gradual accumulates in the ocean and let go ofing the energy when it reaches the land. One of the methods to change over wave power to electrical power is utilizing ‘oscillating H2O column ‘ ( OWC ) . The mechanism is that when the moving ridge rise and falling inside an enclosed camber, it will alternately blows and suctions air through the air turbine to bring forth electricity.
Water power is another signifier of solar energy because the solar radiation heat up the H2O and allow them zap as H2O vapour. The air current so transfers these vapour to the land. The vapour will distill and fall on the land as rain. A portion of H2O will flux into the river and eventually flux back to the ocean. Base on this natural phenomenon, large-scale hydroelectricity production works constructed dikes across rivers to hive away H2O behind the dike. Finally, different H2O degrees built up across the dike. The H2O at the upper degree has a inclination to flux to the lower degree and the drive force is gravitative force. The H2O at the upper degree was allowed to flux across the dike via turbines which couple with generator to bring forth electricity.
For small-scale hydroelectricity production works, it makes usage of the natural flow from rivers and unneeded to construct dikes so as to cut down the environmental impact induced from constructing dikes. However, this type of hydroelectricity production works generate much less electricity when comparison with the large-scale hydroelectricity production works.
As the name implies, tidal energy are caused by gravitative pull of the Moon and the Sun of the oceans which lead to the H2O cyclicity rise and autumn on coastlines. The traditional method to bring forth electricity by utilizing tidal power requires a low dike across the estuary of a suited river. When the tide enters the dike, the H2O degree rises behind the dike. After the H2O degree reach the maximal tallness, the recess of the dike is closed and the H2O which enters the dike will flux back to the sea through turbine-generator so that tackling tidal energy. A newer method to tackle tidal energy is to utilize submerged turbine. Electricity is produced when the tidal base on balls through the submerged turbines that drive the turbines that couple with electricity generator.
Another renewable beginning which is non straight come from solar radiation is geothermic energy. The major beginning of geothermic energy came from the decay of durable radioactive elements in the centre of the Earth. Aquifer, which is the belowground H2O, is the most utile geothermic resources. It can transport the Earth ‘s internal heat to the Earth crust surface. The attendant hot H2O or steam will be used for electricity production or straight use for warming. In fact, whether the geothermic energy is a renewable energy depends on the heat extraction rate and the auxiliary rate. If the extraction rate is greater than the auxiliary rate, it is non considered as renewable energy beginning, and frailty poetry. However, geothermic energy is merely available where there is tectonic or volcanic activity.
The ultimate energy beginning of bioenergy is solar energy and the solar energy is fixed into biomass by photosynthesis in green works degree and others photolithotrophy/ exposure autotrophy being. Bioenergy is the energy recovered from organic affair ( biomass ) . Some of the biomass has been considered as fuel ( biofuel ) for a long clip. Biofuel can be divided into three groups: firewood, organic wastes, and harvests grown, which will be converted into liquid fuel. Firewood is used for direct combustion and so produces wood coal in developing states. It is the major beginning of energy in these states for cookery, warming and generate electricity. Urban waste ( such as effluent and family waste ) , agribusiness and animate being residues can be classified as organic wastes. These organic wastes are used to bring forthing methane under anaerobiotic agitation. Methane is used to run farm machinery. For the harvests, they are used for ethanol production under anaerobiotic agitation.
These sorts of biofuel ( bioethanol and biodiesel ) are the most popular renewable resource in transit fuel.
Presently, transit history for 50 % of planetary oil ingestion. If biofuel can replace the oil, non merely it can cut down the emanation of C dioxide, but besides can salvage rough oil to be used in other facet because petroleum oil is a really of import natural stuff in many production.
hypertext transfer protocol: //www.hedon.info/AgriculturalResidues
[ ] energy systems and sustainability power for a sustainable hereafter edited by godfrey Boyle, British shilling everett and janet ramage
Chapter 3 ( 1 page )
The background of bioenergy and biofuel development
Bioenergy is the oldest fuel used by worlds. Worlds burned wood in cave to maintain warm and cook nutrient. This biofuel is a major fuel beginning in the USA until coal, oil and natural gas ( fossil fuel ) have been discovered by human. Nowadays, dodo fuel is the major fuel beginning in many developed states. However, in many developing states, wood is still the major beginning of fuel. Burning wood straight will let go of smell fume which contains toxic air pollutants such as benzoapyrene, all right atom pollutant, C monoxide, N oxides, and volatile organic compounds. In this respects, firewood is non a desirable biofuel.
hypertext transfer protocol: //www.epa.gov/air/toxicair/community/guide/wood_stoves_oo_sheet.pdf
Other types of liquid-form biofuel, which are the research mark and have been used in developed states, are bioethanol and biodiesel. Bioethanol and biodiesel are still non popular in transit but this biofuel use is bit by bit increasing. Brazil is the state that bioethanol is the most widely used as transit fuel in the universe, for which bioethanol has replaced 50 % of gasolene for transit fuels. The largest bioethanol manufacturer is the USA, which is accounting for approximately 54 % of planetary ethyl alcohol production. Global production of bioethanol reached 76 billion litres in 2009. It has a 10 % growing when compared to bioethanol production in 2008. This production growing rate is contributed chiefly by the USA, Canada, Germany and France.
Global production of biodiesel reached 16.6 billion litres in 2009. It has a 9 % growing when compared to bioethanol production in 2008. From the graph, it shows that biodiesel is less popular when comparison with bioethanol. The major biodiesel manufacturer and consumer is European Union, they produce 50 % of planetary biodiesel.
Harmonizing to A Global Comparison of National Biodiesel Production Potentials published by University of Wisconsin, the upper bound of the world-wide biodiesel production potencies will increase from 47billion litre to 51 billion litres in 2015, which is caused by the addition of agricultural outputs. Malaysia, Indonesia, Argentina, the United States and Brazil accounting for approximately 80 % of world-wide biodesel. These states have good agricultural base and therefore hold comparatively more feedstock for biodesel production. The production cost of biodiesel in these top five manufacturer states, runing from $ 0.49 to $ 0.70 per litre.
First coevals biofuel
The biofuels which are being sold on the market are considered as first coevals biofuel. First coevals biofuel, both bioethanol and biodiesel, are produced from grains, maize, seed, carnal fats and other high sugars and oil content works spices. These sorts of natural stuff can be used as nutrient and eating.