lecture notes energy resources

8/10/2019 Lecture Notes Energy Resources

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ENERGY SOURCESEnergy:-

Energy is a scalarphysical quantitythat describes the amount of

workthat can be performed by a force, an attribute of objects and systems that issubject to a conservation law

Different forms of energy include kinetic, potential, thermal,gravitational, sound,light,elastic, and electromagneticenergy. The forms of energy are often namedafter a related force.

Any form of energy can be transformedinto another form, but the total energyalways remains the same. This principle, the conservation of energy, was firstpostulated in the early !th century, and applies to any isolated system.

Types of EnergyThere are two types of energy

"rimary energy

#econdary energy

Primary Energy

"rimary energy is energy found in nature that has not been subjected to any

conversion or transformation process.

"rimary energy is energy contained in raw fuelsand any other forms of energyreceived by a systemas inputto the system.

The concept is used especially in energy statisticsin the course of compilation ofenergy balances. "rimary energy includes non$renewable energyandrenewableenergy.

Secondary Energy

"rimary energies are transformed in energy conversion processes to moreconvenient forms of energy, such as electrical energy, refined fuels,or syntheticfuels such as hydrogen fuel. %n energy statistics these forms are called energy.#econdary energy is an energy form which has been transformed from anotherone. Electricity is the most common e&ample, being transformed from suchprimary sources as coal, oil, natural gas, and wind.
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Energy Sources

The following are some of the energy sources #olar Energy

'ind Energy

'ater Energy

Tidal Energy

'ave Energy

#olid (iomass

(io )as

)eothermal Energy

Solar Energy

#olar energy is the radiant lightand heatfrom the #unthat has been harnessedby humans since ancient timesusing a range of ever$evolving technologies.#olar radiation along with secondary solar resources such as wind and wavepower, hydroelectricityand biomassaccount for most of the available renewableenergyon Earth. *nly a minuscule fraction of the available solar energy is used.

#olar power provides electrical generation by means of heat engines orphotovoltaics. *nce converted, its uses are limited only by human ingenuity. Apartial list of solar applications includes space heating and cooling through solararchitecture, potable watervia distillationand disinfection, daylighting,hot water,thermal energy for cooking, and high temperature process heat for industrial

purposes.

#olar technologies are broadly characteri+ed as either passive solar or activesolardepending on the way they capture, convert and distribute sunlight. Activesolar techniques include the use of photovoltaic panels and solar thermalcollectors with electrical or mechanical equipment- to convert sunlight into usefuloutputs. "assive solar techniques include orienting a building to the #un,selecting materials with favorable thermal massor light dispersing properties,and designing spaces that naturally circulate air.

Types of Solar System

There are two types of solar system

Active #olar #ystem

"assive #olar #ystem
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cti!e Solar System

An active solar system is a system that uses a mechanical device, such aspumps or fans run by electricity in addition to solar energy, to transport air orwater between a solar collector and the interior of a building for heating or

cooling.

Passi!e Solar System

A passive solar system is a system that distributes collected heat via directtransfer from a thermal mass rather than mechanical power. "assive systemsrely on building design and materials to collect and store heat and to createnatural ventilation for cooling.

pplication of Solar Energy

Solar lighting

Water heating

Heating, cooling and ventilation

Electrical generation

Solar "ig#ting

%n the /th century artificial lighting became the main source of interiorillumination but daylighting techniques and hybrid solar lighting solutions areways to reduce energy consumption. Daylightingsystems collect and distributesunlight to provide interior illumination. This passive technology directly offsetsenergy use by replacing artificial lighting, and indirectly offsets non$solar energyuse by reducing the need for air$conditioning. Although difficult to quantify, theuse of natural lighting also offers physiological and psychological benefitscompared to artificial lighting. Daylighting design implies careful selection of

window types, si+es and orientation0 e&terior shading devices may be consideredas well. %ndividual features include sawtooth roofs, clerestory windows, lightshelves, skylights and light tubes. They may be incorporated into e&istingstructures, but are most effective when integrated into a solar design packagethat accounts for factors such as glare, heat flu& and time$of$use. 'hendaylighting features are properly implemented they can reduce lighting$relatedenergy requirements by 12.
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3ybrid solar lighting is an active solarmethod of providing interior illumination.3#4 systems collect sunlight using focusing mirrors that track the #unand useoptical fibersto transmit it inside the building to supplement conventional lighting.%n single$story applications these systems are able to transmit 1/2 of the directsunlight received.

#olar lights that charge during the day and light up at dusk are a common sightalong walkways.

Although daylight saving time is promoted as a way to use sunlight to saveenergy, recent research has been limited and reports contradictory results5several studies report savings, but just as many suggest no effect or even a netloss, particularly when gasolineconsumption is taken into account. Electricity useis greatly affected by geography, climate and economics, making it hard togenerali+e from single studies.

$ater %eating#olar hot water systems use sunlight to heat water. %n low geographical latitudesbelow 6/ degrees- from 7/ to 8/2 of the domestic hot water use withtemperatures up to 7/ 9: can be provided by solar heating systems. The mostcommon types of solar water heaters are evacuated tube collectors 662- andgla+ed flat plate collectors ;62- generally used for domestic hot water0 andungla+ed plastic collectors 2- used mainly to heat swimming pools.

As of //8, the total installed capacity of solar hot water systems isappro&imately 16 )'.:hina is the world leader in their deployment with 8/ )'

installed as of //7 and a long term goal of / )' by //. %srael and :yprusare the per capita leaders in the use of solar hot water systems with over !/2 ofhomes using them. %n the


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can be used in cold temperate areas to maintain warmth as well. The si+e andplacement of thermal mass depend on several factors such as climate,daylighting and shading conditions. 'hen properly incorporated, thermal massmaintains space temperatures in a comfortable range and reduces the need forau&iliary heating and cooling equipment.

A solar chimney or thermal chimney, in this conte&t- is a passive solar ventilationsystem composed of a vertical shaft connecting the interior and e&terior of abuilding. As the chimney warms, the air inside is heated causing an updraftthatpulls air through the building. "erformance can be improved by using gla+ing andthermal mass materials in a way that mimics greenhouses.

Deciduoustrees and plants have been promoted as a means of controlling solarheating and cooling. 'hen planted on the southern side of a building, theirleaves provide shade during the summer, while the bare limbs allow light to passduring the winter. #ince bare, leafless trees shade ; to of incident solar

radiation, there is a balance between the benefits of summer shading and thecorresponding loss of winter heating. %n climates with significant heating loads,deciduous trees should not be planted on the southern side of a building becausethey will interfere with winter solar availability. They can, however, be used on theeast and west sides to provide a degree of summer shading without appreciablyaffecting winter solar gain.

Electrical Generation

#unlight can be converted into electricity using photovoltaics ">-, concentratingsolar power:#"-, and various e&perimental technologies. "> has mainly been

used to power small and medium$si+ed applications, from the calculatorpoweredby a single solar cell to off$grid homes powered by a photovoltaic array. Borlarge$scale generation, :#" plants like #E)#have been the norm but recentlymulti$megawatt "> plants are becoming common. :ompleted in //8, the6 C' power station in :lark :ounty, evada and the / C' site in(enei&ama, #pain are characteristic of the trend toward larger photovoltaicpower stations in the


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$ind Energy

'ind power is the conversion of wind energy into a useful form, such aselectricity, using wind turbines.At the end of //=, worldwide nameplate capacityof wind$powered generators was . gigawatts)'-. 'ind power producesabout .12 of worldwide electricity use, and is growing rapidly, having doubled inthe three years between //1 and //=. #everal countries have achievedrelatively high levels of wind power penetration, such as !2 of stationaryelectricity production in Denmark, 2 in #pain and "ortugal, and 82 in)ermanyand the Fepublic of %reland in //=. As of Cay //!, eighty countriesaround the world are using wind power on a commercial basis.

4arge$scale wind farms are typically connected to the local electric power

transmissionnetwork0 smaller turbines are used to provide electricity to isolatedlocations.


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A wind turbine in which the a&is of the rotorGs rotation is parallel to the windstream and the ground. All grid$connected commercial wind turbines today arebuilt with a propeller$type rotor on a hori+ontal a&is i.e. a hori+ontal main shaft-.Cost hori+ontal a&is turbines built today are two$ or three$bladed, although somehave fewer or more blades. The purpose of the rotor is to convert the linear

motion of the wind into rotational energy that can be used to drive a generator.The same basic principle is used in a modern water turbine, where the flow ofwater is parallel to the rotational a&is of the turbine blades.

The wind passes over both surfaces of the airfoil shaped blade but passes morerapidly over the longer upper- side of the airfoil, thus creating a lower$pressurearea above the airfoil. The pressure differential between top and bottom surfacesresults in aerodynamic lift. %n an aircraft wing, this force causes the airfoil to rise,lifting the aircraft off the ground. #ince the blades of a wind turbine areconstrained to move in a plane with the hub as its center, the lift force causesrotation about the hub. %n addition to the lift force, a drag force perpendicular to

the lift force impedes rotor rotation. A prime objective in wind turbine design is forthe blade to have a relatively high lift$to$drag ratio. This ratio can be varied alongthe length of the blade to optimi+e the turbineHs energy output at various windspeeds.

&ertical )is $ind Tur'ine

A type of wind turbinein which the a&is of rotation is perpendicular to the windstream and the ground. >A'Ts work somewhat like a classical water wheel inwhich water arrives at a right angle perpendicular- to the rotational a&is shaft- ofthe water wheel. >ertical$a&is wind turbines fall into two major categories5

Darrieus turbines and #avonius turbines. either type is in wide use today.

The basic theoretical advantages of a vertical a&is machine are5 The generator, gearbo& etc. may be placed on the ground, and a tower is

not essential for the machine A yaw mechanism isnGt needed to turn the rotor against the wind.

The basic disadvantages are5

'ind speeds are very low close to ground level, so although a tower isnGt

essential, the wind speeds will be very low on the lower part of the rotor The overall efficiency of the vertical a&is machines is not impressive

The machine is not self$starting, i.e. a Darrieus machine needs a IpushI

before it will start. This is only a minor inconvenience for a grid$connectedturbine, however, since the generator may be used as a motor drawingcurrent from the grid to start the machine
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Feplacing the main bearing for the rotor necessitates removing the rotor

on both a hori+ontal and a vertical a&is machine. %n the case of the latter, itmeans tearing the whole machine down

$ater Energy

3ydroelectricity is electricity generated by hydropower, i.e., the production ofpower through use of the gravitational force of falling or flowing water. %t is themost widely used form of renewable energy. *nce a hydroelectric comple& isconstructed, the project produces no direct waste, and has a considerably loweroutput level of the greenhouse gascarbon dio&ide:*- than fossil fuelpoweredenergy plants. 'orldwide, hydroelectricity supplied an estimated =7 )'e in//1. This was appro&imately /2 of the worldGs electricity, and accounted forabout ==2 of electricity from renewable sources.

Electricity generation

Cost hydroelectric power comes from the potential energy of dammed waterdriving a water turbine and generator. %n this case the energy e&tracted from thewater depends on the volume and on the difference in height between the sourceand the waterGs outflow. This height difference is called the head.The amount ofpotential energyin water is proportional to the head. To obtain very high head,water for a hydraulic turbine may be run through a large pipe called a penstock.

"umped storage hydroelectricity produces electricity to supply high peak

demands by moving water between reservoirs at different elevations. At times oflow electrical demand, e&cess generation capacity is used to pump water into thehigher reservoir. 'hen there is higher demand, water is released back into thelower reservoir through a turbine. "umped storage schemes currently provide theonly commercially important means of large$scale grid energy storage andimprove the daily load factorof the generation system. 3ydroelectric plants withno reservoir capacity are called run$of$the$river plants, since it is not thenpossible to store water. A tidal powerplant makes use of the daily rise and fall ofwater due to tides0 such sources are highly predictable, and if conditions permitconstruction of reservoirs, can also be dispatchable to generate power duringhigh demand periods.

4ess common types of hydro schemes use waterGs kinetic energyor undammedsources such as undershot waterwheels.

A simple formula for appro&imating electric power production at a hydroelectricplant is5 PJ hrgk, where Pis "ower in kilowatts, his height in meters, ris flowrate in cubic meters per second, gis acceleration due to gravityof !.= ms, and
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kis a coefficient of efficiency ranging from / to . Efficiency is often higher withlarger and more modern turbines.

Annual electric energy production depends on the available water supply. %nsome installations the water flow rate can vary by a factor of /5 over the course

of a year.

d!antages

Economics

The major advantage of hydroelectricity is elimination of the cost of fuel. The costof operating a hydroelectric plant is nearly immune to increases in the cost offossil fuelssuch as oil, natural gas or coal, and no imports are needed.

3ydroelectric plants also tend to have longer economic lives than fuel$firedgeneration, with some plants now in service which were built 1/ to // yearsago. *perating labor cost is also usually low, as plants are automated and havefew personnel on site during normal operation.

'here a dam serves multiple purposes, a hydroelectric plant may be added withrelatively low construction cost, providing a useful revenue stream to offset thecosts of dam operation. %t has been calculated that the sale of electricity from theThree )orges Damwill cover the construction costs after 1 to = years of fullgeneration.

Greenhouse gas emissions

#ince hydroelectric dams do not burn fossil fuels, they do not directly producecarbon dio&ide a greenhouse gas-. 'hile some carbon dio&ide is producedduring manufacture and construction of the project, this is a tiny fraction of theoperating emissions of equivalent fossil$fuel electricity generation.

Related activities

Feservoirs created by hydroelectric schemes often provide facilities for water

sports, and become tourist attractions in themselves. %n some countries,aquaculture in reservoirs is common. Culti$use dams installed for irrigationsupport agriculturewith a relatively constant water supply. 4arge hydro dams cancontrol floods, which would otherwise affect people living downstream of theproject.

Geo T#ermal
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)eothermal power from the )reek roots geo, meaning earth, and thermos,meaning heat- is powere&tracted from heat stored in the earth. This geothermalenergyoriginates from the original formation of the planet, from radioactive decayof minerals, and from solar energy absorbed at the surface. %t has been used forspace heating and bathing since ancient roman times, but is now better known

for generating electricity. About / )' of geothermal electric capacity is installedaround the world as of //8, generating /.;2 of global electricity demand. Anadditional = )' of direct geothermal heating capacity is installed for districtheating, space heating, spas, industrial processes, desalination and agriculturalapplications.

)eothermal power is cost effective, reliable, and environmentally friendly, but haspreviously been geographically limited to areas near tectonic plate boundaries.Fecent technological advances have dramatically e&panded the range and si+eof viable resources, especially for direct applications such as home heating.)eothermal wells tend to release greenhouse gases trapped deep within the

earth, but these emissions are much lower than those of conventional fossil fuels.As a result, geothermal power has the potential to help mitigate global warmingifwidely deployed instead of fossil fuels.

Geot#ermal electricity plants

)eothermal electric plants have until recently been built e&clusively on the edgesof tectonic plates where high temperature geothermal resources are availablenear the surface. The development of binary cycle power plants andimprovements in drilling and e&traction technology has opened the hope thatenhanced geothermal systemsmight be viable over a much greater geographical

range. A demonstration project has recently been completed in 4andau$"fal+,)ermany, and others are under construction in #oult+$sous$BorKts, Brance and:ooper (asin,Australia.

Non-electricity generation application

Appro&imately seventy countries made direct use of a total of 8/ "? ofgeothermal heatingin //6. Core than half of this energy was used for spaceheating, and a third was used for heated pools. The remainder was used forindustrial and agricultural applications. The global installed capacity was = )',

but capacity factors tend to be low around /2- since the heat is mostly neededin the winter. The above figures include == "? of space heating e&tracted by anestimated million geothermal heat pumpswith a total capacity of 1 )'. )lobalgeothermal heat pump capacity is growing by /2 annually.

Direct application of geothermal heat for space heating is far more efficient thanelectricity generation and has less demanding temperature requirements. %t maycome from waste heat supplied by co$generation from a geothermal electrical
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plant or from smaller wells or heat e&changers buried in the shallow ground. As aresult it is viable over a much greater geographical range than electricitygeneration. 'here natural hot springsare available, the water may be pipeddirectly into radiators. %f the shallow ground is hot but dry, earth tubes ordownhole heat e&changers may be used without a heat pump. (ut even in areas

where the shallow ground is too cold to provide comfort directly, it is still warmerthan the winter air. #easonal variations in ground temperature diminish anddisappear completely below /m of depth. That heat can be e&tracted with ageothermal heat pumpmore efficiently than it can be generated by conventionalfurnaces. )eothermal heat pumps can be used essentially anywhere.

En!ironmental impacts

)eothermal fluids drawn from the deep earth may carry a mi&ture of gases withthem, notably carbon dio&ide and hydrogen sulfide. 'hen released to theenvironment, these pollutants contribute to global warming, acid rain, and

no&ious smells in the vicinity of the plant. E&isting geothermal electric plants emitan average of kg of :* per C'h of electricity, a small fraction of theemission intensityof conventional fossil fuel plants. #ome are equipped withemissions$controlling systems that reduces the e&haust of acids and volatiles.

%n addition to dissolved gases, hot water from geothermal sources may containtrace amounts of dangerous elements such as mercury, arsenic, and antimonywhich, if disposed of into rivers, can render their water unsafe to drink.)eothermal plants can theoretically inject these substances, along with thegases, back into the earth, in a form of carbon capture and storage.

:onstruction of the power plants can adversely affect land stability in thesurrounding region. #ubsidence has occurred in the 'airakei field in ewLealand and in #taufen im (reisgau, )ermany. Enhanced geothermal systemscan trigger earthquakesas part of the hydraulic fracturingprocess. The project in(asel, #wit+erlandwas suspended because more than /,/// seismic eventmeasuring up to ;.6 on the Fichter #caleoccurred over the first 7 days of waterinjection.

)eothermal has minimal requirements for land use and freshwater. E&istinggeothermal plants use $= acres per megawatt C'- versus 1$/ acres per C'for nuclear operations and ! acres per C' for coal power plants. They use /

liters of freshwater per C'h versus over /// litres per C'h for nuclear, coal, oroil.

*iogas
http://en.wikipedia.org/wiki/Hot_springshttp://en.wikipedia.org/wiki/Radiatorshttp://en.wikipedia.org/wiki/Earth_tubeshttp://en.wikipedia.org/wiki/Downhole_heat_exchangerhttp://en.wikipedia.org/wiki/Geothermal_heat_pumphttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Hydrogen_sulfidehttp://en.wikipedia.org/wiki/Global_warminghttp://en.wikipedia.org/wiki/Acid_rainhttp://en.wikipedia.org/wiki/Emission_intensityhttp://en.wikipedia.org/wiki/Carbon_capture_and_storagehttp://en.wikipedia.org/wiki/Wairakei_fieldhttp://en.wikipedia.org/wiki/Staufen_im_Breisgauhttp://en.wikipedia.org/wiki/Enhanced_geothermal_systemshttp://en.wikipedia.org/wiki/Earthquakehttp://en.wikipedia.org/wiki/Hydraulic_fracturinghttp://en.wikipedia.org/wiki/Baselhttp://en.wikipedia.org/wiki/Switzerlandhttp://en.wikipedia.org/wiki/Richter_Scalehttp://en.wikipedia.org/wiki/Hot_springshttp://en.wikipedia.org/wiki/Radiatorshttp://en.wikipedia.org/wiki/Earth_tubeshttp://en.wikipedia.org/wiki/Downhole_heat_exchangerhttp://en.wikipedia.org/wiki/Geothermal_heat_pumphttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Hydrogen_sulfidehttp://en.wikipedia.org/wiki/Global_warminghttp://en.wikipedia.org/wiki/Acid_rainhttp://en.wikipedia.org/wiki/Emission_intensityhttp://en.wikipedia.org/wiki/Carbon_capture_and_storagehttp://en.wikipedia.org/wiki/Wairakei_fieldhttp://en.wikipedia.org/wiki/Staufen_im_Breisgauhttp://en.wikipedia.org/wiki/Enhanced_geothermal_systemshttp://en.wikipedia.org/wiki/Earthquakehttp://en.wikipedia.org/wiki/Hydraulic_fracturinghttp://en.wikipedia.org/wiki/Baselhttp://en.wikipedia.org/wiki/Switzerlandhttp://en.wikipedia.org/wiki/Richter_Scale


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(iogas typically refers to a gasproduced by the biological breakdown of organicmatterin the absence of o&ygen.(iogas originates from biogenic material and isa type of biofuel.

*ne type of biogas is produced by anaerobic digestion or fermentation of

biodegradable materials such as biomass, manureor sewage, municipal waste,green wasteand energy crops. This type of biogas comprises primarily methaneand carbon dio&ide. The other principal type of biogas is wood gas which iscreated by gasification of wood or other biomass. This type of biogas iscomprised primarily of nitrogen, hydrogen, and carbon mono&ide, with traceamounts of methane.

*iogas plant

(iogas is practically produced as landfill gas 4B)- or digestergas.A biogas plantis the name often given to an anaerobic digester that treats farm wastes or

energy crops.

(iogas can be produced utili+ing anaerobic digesters. These plants can be fedwith energy crops such as mai+e silage or biodegradable wastes includingsewage sludge and food waste.

4andfill gas is produced by wet organic waste decomposing under anaerobicconditions in a landfill. The waste is covered and compressed mechanically andby the weight of the material that is deposited from above. This material preventso&ygen from accessing the waste and anaerobic microbes thrive. This gas buildsup and is slowly released into the atmosphere if the landfill site has not been

engineered to capture the gas. 4andfill gas is ha+ardous for three key reasons.4andfill gas becomes e&plosive when it escapes from the landfill and mi&es witho&ygen. The lower e&plosive limit is 12 methane and the upper e&plosive limit is12 methane. The methane contained within biogas is / times more potent asa greenhouse gas than carbon dio&ide. Therefore uncontained landfill gas whichescapes into the atmosphere may significantly contribute to the effects of globalwarming. %n addition to this volatile organic compounds>*:s- contained withinlandfill gas contribute to the formation of photochemical smog.

pplications

(iogas can be utili+ed for electricity production on sewage works , in a :3"gasengine, where the waste heat from the engine is conveniently used to heat thedigester0 cooking, space heating, water heating and process heating. %fcompressed, it can replace compressed natural gasfor use in vehicles, where itcan fuel an internal combustion engineor fuel cellsand is a much more effectivedisplacer of carbon dio&ide than the normal use in on$site :3" plants.
http://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Organic_matterhttp://en.wikipedia.org/wiki/Organic_matterhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Biofuelhttp://en.wikipedia.org/wiki/Anaerobic_digestionhttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Biomasshttp://en.wikipedia.org/wiki/Manurehttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Municipal_wastehttp://en.wikipedia.org/wiki/Green_wastehttp://en.wikipedia.org/wiki/Energy_crophttp://en.wikipedia.org/wiki/Methanehttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Wood_gashttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Hydrogenhttp://en.wikipedia.org/wiki/Carbon_monoxidehttp://en.wikipedia.org/wiki/Methanehttp://en.wikipedia.org/wiki/Anaerobic_digesterhttp://en.wikipedia.org/wiki/Biodegradable_wastehttp://en.wikipedia.org/wiki/Volatile_organic_compoundhttp://en.wikipedia.org/wiki/Photochemical_smoghttp://en.wikipedia.org/wiki/Cogenerationhttp://en.wikipedia.org/wiki/Gas_enginehttp://en.wikipedia.org/wiki/Gas_enginehttp://en.wikipedia.org/wiki/Water_heatinghttp://en.wikipedia.org/wiki/Compressed_natural_gashttp://en.wikipedia.org/wiki/Internal_combustion_enginehttp://en.wikipedia.org/wiki/Fuel_cellhttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Organic_matterhttp://en.wikipedia.org/wiki/Organic_matterhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Biofuelhttp://en.wikipedia.org/wiki/Anaerobic_digestionhttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Biomasshttp://en.wikipedia.org/wiki/Manurehttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Municipal_wastehttp://en.wikipedia.org/wiki/Green_wastehttp://en.wikipedia.org/wiki/Energy_crophttp://en.wikipedia.org/wiki/Methanehttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Wood_gashttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Hydrogenhttp://en.wikipedia.org/wiki/Carbon_monoxidehttp://en.wikipedia.org/wiki/Methanehttp://en.wikipedia.org/wiki/Anaerobic_digesterhttp://en.wikipedia.org/wiki/Biodegradable_wastehttp://en.wikipedia.org/wiki/Volatile_organic_compoundhttp://en.wikipedia.org/wiki/Photochemical_smoghttp://en.wikipedia.org/wiki/Cogenerationhttp://en.wikipedia.org/wiki/Gas_enginehttp://en.wikipedia.org/wiki/Gas_enginehttp://en.wikipedia.org/wiki/Water_heatinghttp://en.wikipedia.org/wiki/Compressed_natural_gashttp://en.wikipedia.org/wiki/Internal_combustion_enginehttp://en.wikipedia.org/wiki/Fuel_cell


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Cethane within biogas can be concentrated via a biogas upgraderto the samestandards as fossil natural gas, and becomes biomethane. %f the local gasnetwork allows for this, the producer of the biogas may utili+e the local gasdistribution networks. )as must be very clean to reach pipeline quality, and mustbe of the correct composition for the local distribution network to accept. :arbon

dio&ide, 'ater,hydrogen sulfideand particulatesmust be removed if present. %fconcentrated and compressed it can also be used in vehicle transportation.:ompressed biogas is becoming widely used in #weden, #wit+erland and)ermany. A biogas$powered train has been in service in #weden since //1.

(ates, an inventor, lived in Devon,


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!th century, wood$fired steam engines were common, contributing significantlyto industrial revolution unhealthy air pollution. :oal is a form of biomass that hasbeen compressed over millennia to produce a non$renewable, highly$pollutingfossil fuel.

'ood and its byproducts can now be converted through processes such asgasification into biofuels such as woodgas, biogas, methanol or ethanol fuel0although further development may be required to make these methods affordableand practical. #ugar caneresidue, wheatchaff, corn cobsand other plant mattercan be, and are, burned quite successfully. The net carbon dio&ide emissionsthat are added to the atmosphere by this process are only from the fossil fuel thatwas consumed to plant, fertili+e, harvest and transport the biomass.

"rocesses to harvest biomass from short$rotation trees like poplarsand willowsand perennial grasses such as switchgrass, phalaris, and miscanthus, requireless frequent cultivation and less nitrogen than do typical annual crops.

"elleti+ingmiscanthus and burning it to generate electricity is being studied andmay be economically viable.

Tidal Energy

Tidal power, sometimes called tidal energy, is a form of hydropowerthat convertsthe energy of tidesinto electricity or other useful forms of power. Although not yetwidely used, tidal power has potential for future electricity generation. Tides aremore predictable than wind energy and solar power.

Categories of Tidal Po+erTidal power can be classified into three main types5

Tidal stream systems make use of the kinetic energyof moving water

to power turbines, in a similar way to windmills that use moving air.This method is gaining in popularity because of the lower cost andlower ecological impact compared to barrages.

(arrages make use of the potential energyin the difference in height

or head- between high and low tides. (arrages are essentially damsacross the full width of a tidal estuary, and suffer from very high civil

infrastructure costs, a worldwide shortage of viable sites, andenvironmental issues.

Tidal lagoons, are similar to barrages, but can be constructed as self

contained structures, not fully across an estuary, and are claimed toincur much lower cost and impact overall. Burthermore they can beconfigured to generate continuously which is not the case withbarrages.
http://en.wikipedia.org/wiki/Non-renewable_energyhttp://en.wikipedia.org/wiki/Gasificationhttp://en.wikipedia.org/wiki/Woodgashttp://en.wikipedia.org/wiki/Biogashttp://en.wikipedia.org/wiki/Sugar_canehttp://en.wikipedia.org/wiki/Crop_residuehttp://en.wikipedia.org/wiki/Wheathttp://en.wikipedia.org/wiki/Chaffhttp://en.wikipedia.org/wiki/Maizehttp://en.wikipedia.org/wiki/Biomasshttp://en.wikipedia.org/wiki/Poplarshttp://en.wikipedia.org/wiki/Willowshttp://en.wikipedia.org/wiki/Switchgrasshttp://en.wikipedia.org/wiki/Phalarishttp://en.wikipedia.org/wiki/Miscanthushttp://en.wikipedia.org/wiki/Pelletizinghttp://en.wikipedia.org/wiki/Hydropowerhttp://en.wikipedia.org/wiki/Tidehttp://en.wikipedia.org/wiki/Electricity_generationhttp://en.wikipedia.org/wiki/Wind_energyhttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Barragehttp://en.wikipedia.org/wiki/Potential_energyhttp://en.wikipedia.org/wiki/Hydraulic_headhttp://en.wikipedia.org/wiki/Damhttp://en.wikipedia.org/wiki/Lagoonhttp://en.wikipedia.org/wiki/Non-renewable_energyhttp://en.wikipedia.org/wiki/Gasificationhttp://en.wikipedia.org/wiki/Woodgashttp://en.wikipedia.org/wiki/Biogashttp://en.wikipedia.org/wiki/Sugar_canehttp://en.wikipedia.org/wiki/Crop_residuehttp://en.wikipedia.org/wiki/Wheathttp://en.wikipedia.org/wiki/Chaffhttp://en.wikipedia.org/wiki/Maizehttp://en.wikipedia.org/wiki/Biomasshttp://en.wikipedia.org/wiki/Poplarshttp://en.wikipedia.org/wiki/Willowshttp://en.wikipedia.org/wiki/Switchgrasshttp://en.wikipedia.org/wiki/Phalarishttp://en.wikipedia.org/wiki/Miscanthushttp://en.wikipedia.org/wiki/Pelletizinghttp://en.wikipedia.org/wiki/Hydropowerhttp://en.wikipedia.org/wiki/Tidehttp://en.wikipedia.org/wiki/Electricity_generationhttp://en.wikipedia.org/wiki/Wind_energyhttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Barragehttp://en.wikipedia.org/wiki/Potential_energyhttp://en.wikipedia.org/wiki/Hydraulic_headhttp://en.wikipedia.org/wiki/Damhttp://en.wikipedia.org/wiki/Lagoon


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Codern advances in turbine technology may eventually see large amounts ofpower generated from the ocean, especially tidal currents using the tidal streamdesigns but also from the major thermal current systems such as the )ulf#tream, which is covered by the more general term marine current power. Tidalstream turbines may be arrayed in high$velocity areas where natural tidal current

flows are concentrated such as the west and east coasts of :anada, the #trait of)ibraltar, the (osporus, and numerous sites in #outheast Asiaand Australia.#uch flows occur almost anywhere where there are entrances to bays and rivers,or between land masses where water currents are concentrated.

Tidal Stream Generators

A relatively new technology, tidal stream generators draw energy from currents inmuch the same way as wind turbines. The higher density of water, =; times thedensity of air, means that a single generator can provide significant power at lowtidal flow velocities compared with wind speed-. )iven that power varies with the

density of medium and the cube of velocity, it is simple to see that water speedsof nearly one$tenth of the speed of wind provide the same power for the samesi+e of turbine system. 3owever this limits the application in practice to placeswhere the tide moves at speeds of at least knots ms- even close to neaptides.

#ince tidal stream generators are an immature technology no commercial scaleproduction facilities are yet routinely supplying power-, no standard technologyhas yet emerged as the clear winner, but a large variety of designs are beinge&perimented with, some very close to large scale deployment. #everalprototypes have shown promise with many companies making bold claims, some

of which are yet to be independently verified, but they have not operatedcommercially for e&tended periods to establish performances and rates of returnon investments.

Energy calculations

>arious turbine designs have varying efficiencies and therefore varying poweroutput. %f the efficiency of the turbine I:pI is known the equation below can beused to determine the power output.

The energy available from these kinetic systems can be e&pressed as5

" J :p & /.1 & M & A & >N

where5

:p is the turbine coefficient of performance" J the power generated in watts-
http://en.wikipedia.org/wiki/Turbinehttp://en.wikipedia.org/wiki/Gulf_Streamhttp://en.wikipedia.org/wiki/Gulf_Streamhttp://en.wikipedia.org/wiki/Marine_current_powerhttp://en.wikipedia.org/wiki/Strait_of_Gibraltarhttp://en.wikipedia.org/wiki/Strait_of_Gibraltarhttp://en.wikipedia.org/wiki/Bosporushttp://en.wikipedia.org/wiki/Southeast_Asiahttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Neaphttp://en.wikipedia.org/wiki/Turbinehttp://en.wikipedia.org/wiki/Gulf_Streamhttp://en.wikipedia.org/wiki/Gulf_Streamhttp://en.wikipedia.org/wiki/Marine_current_powerhttp://en.wikipedia.org/wiki/Strait_of_Gibraltarhttp://en.wikipedia.org/wiki/Strait_of_Gibraltarhttp://en.wikipedia.org/wiki/Bosporushttp://en.wikipedia.org/wiki/Southeast_Asiahttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Neap


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M J the density of the water seawater is /1 kgmN-A J the sweep area of the turbine in mO->N J the velocity of the flow cubed i.e. > & > & >-

Felative to an open turbine in free stream, shrouded turbines are capable of as

much as ; to 6 times the power of the same rotor in open flow, depending on thewidth of the shroud. 3owever, to measure the efficiency, one must compare thebenefits of a larger rotor with the benefits of the shroud.

$a!e Energy

'ave power is the transport of energyby ocean surface waves,and the captureof that energy to do useful work@ for e&ample for electricity generation, waterdesalination, or the pumping of water into reservoirs-. 'ave power is arenewable energysource.

P#ysical concepts

'aves are generated by wind passing over the sea5 as long as the wavespropagate slower than the wind speed just above the waves, there is an energytransfer from the wind to the most energetic waves. (oth air pressure differencesbetween the upwind and the lee side of a wave crest, as well as friction on thewater surface by the wind shear stresscauses the growth of the waves. Thewave heightincreases with increases in see *cean surface wave-5

wind speed,

time duration of the wind blowing, fetch@ the distance of open water that the wind has blown over, and

water depth in case of shallow watereffects, for water depths less

than half the wavelength-.

%n general, large waves are more powerful. #pecifically, wave power isdetermined by wave height, wave speed, wavelength, and water density.

'ave si+e is determined by wind speed and fetch the distance over which thewind e&cites the waves- and by the depth and topography of the seafloor whichcan focus or disperse the energy of the waves-. A given wind speed has a

matching practical limit over which time or distance will not produce larger waves.This limit is called a Ifully developed sea.I

*scillatory motion is highest at the surface and diminishes e&ponentially withdepth. 3owever, for standing waves clapotis- near a reflecting coast, waveenergy is also present as pressure oscillations at great depth, producingmicroseisms. These pressure fluctuations at greater depth are too small to beinteresting from the point of view of wave power.
http://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Ocean_surface_wavehttp://en.wikipedia.org/wiki/Mechanical_workhttp://en.wikipedia.org/wiki/Electricity_generationhttp://en.wikipedia.org/wiki/Water_desalinationhttp://en.wikipedia.org/wiki/Water_desalinationhttp://en.wikipedia.org/wiki/Pumphttp://en.wikipedia.org/wiki/Reservoirhttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Crest_(physics)http://en.wikipedia.org/wiki/Shear_stresshttp://en.wikipedia.org/wiki/Wave_heighthttp://en.wikipedia.org/wiki/Ocean_surface_wavehttp://en.wikipedia.org/wiki/Fetchhttp://en.wikipedia.org/wiki/Waves_and_shallow_waterhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Ocean_surface_wave#Science_of_waveshttp://en.wikipedia.org/wiki/Standing_waveshttp://en.wikipedia.org/wiki/Clapotishttp://en.wikipedia.org/wiki/Microseismhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Ocean_surface_wavehttp://en.wikipedia.org/wiki/Mechanical_workhttp://en.wikipedia.org/wiki/Electricity_generationhttp://en.wikipedia.org/wiki/Water_desalinationhttp://en.wikipedia.org/wiki/Water_desalinationhttp://en.wikipedia.org/wiki/Pumphttp://en.wikipedia.org/wiki/Reservoirhttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Crest_(physics)http://en.wikipedia.org/wiki/Shear_stresshttp://en.wikipedia.org/wiki/Wave_heighthttp://en.wikipedia.org/wiki/Ocean_surface_wavehttp://en.wikipedia.org/wiki/Fetchhttp://en.wikipedia.org/wiki/Waves_and_shallow_waterhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Ocean_surface_wave#Science_of_waveshttp://en.wikipedia.org/wiki/Standing_waveshttp://en.wikipedia.org/wiki/Clapotishttp://en.wikipedia.org/wiki/Microseism


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The waves propagate on the ocean surface, and the wave energy is alsotransported hori+ontally with the group velocity. The mean transport rate of thewave energy through a vertical planeof unit width, parallel to a wave crest, iscalled the wave energy flu&or wave power, which must not be confused with theactual power generated by a wave power device-.

$a!e Po+er ,ormula

%n deep water, if the water depth is larger than half the wavelength, the waveenergy flu& is

where

" the wave energy flu& per unit wave crest length k'm-0

3m/ is the significant wave height meter-, as measured by wave buoysand predicted by wave forecast models. (y definition, 3m/is four times thestandard deviationof the water surface elevation0

T is the wave periodsecond-0

M is the mass densityof the water kgm;-, and g is the acceleration by gravityms-.

The above formula states that wave power is proportional to the wave period andto the squareof the wave height. 'hen the significant wave height is given in

meters, and the wave period in seconds, the result is the wave power in kilowattsk'- per meter wavefront length.

E&ample5 :onsider moderate ocean swells, in deep water, a few kilometers off acoastline, with a wave height of ; meters and a wave period of = seconds.


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Wave Energy and Wave Energy Flux

%n a sea state, the averageenergydensity per unit area of gravity waveson thewater surface is proportional to the wave height squared, according to linearwave theory5

where E is the mean wave energy density per unit hori+ontal area ?m-, thesum of kineticand potential energydensity per unit hori+ontal area. The potentialenergy density is equal to the kinetic energy,P6Qboth contributing half to the waveenergy density E, as can be e&pected from the equipartition theorem. %n oceanwaves, surface tension effects are negligible for wavelengths above a fewdecimeters.

As the waves propagate, their energy is transported. The energy transportvelocity is the group velocity. As a result, the wave energy flu&, through a verticalplane of unit width perpendicular to the wave propagation direction, is equal to5

with cgthe group velocity ms-. Due to the dispersion relationfor water wavesunder the action of gravity, the group velocity depends on the wavelengthR, orequivalently, on the wave periodT. Burther, the dispersion relation is a function ofthe water depth h. As a result, the group velocity behaves differently in the limitsof deep and shallow water, and at intermediate depths

Deep water corresponds with a water depth larger than half the wavelength,which is the common situation in the sea and ocean. %n deep water, longer periodwaves propagate faster and transport their energy faster. The deep$water groupvelocity is half the phase velocity. %n shallow water, for wavelengths larger thantwenty times the water depth, as found quite often near the coast, the groupvelocity is equal to the phase velocity.
http://en.wikipedia.org/wiki/Sea_statehttp://en.wikipedia.org/wiki/Averagehttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Gravity_wavehttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Potential_energyhttp://en.wikipedia.org/wiki/Wave_power#cite_note-Phillips-3http://en.wikipedia.org/wiki/Equipartition_theorem#Potential_energy_and_harmonic_oscillatorshttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Decimetrehttp://en.wikipedia.org/wiki/Group_velocityhttp://en.wikipedia.org/wiki/Fluxhttp://en.wikipedia.org/wiki/Dispersion_(water_waves)http://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Period_(physics)http://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Phase_velocityhttp://en.wikipedia.org/wiki/Waves_and_shallow_waterhttp://en.wikipedia.org/wiki/Sea_statehttp://en.wikipedia.org/wiki/Averagehttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Gravity_wavehttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Potential_energyhttp://en.wikipedia.org/wiki/Wave_power#cite_note-Phillips-3http://en.wikipedia.org/wiki/Equipartition_theorem#Potential_energy_and_harmonic_oscillatorshttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Decimetrehttp://en.wikipedia.org/wiki/Group_velocityhttp://en.wikipedia.org/wiki/Fluxhttp://en.wikipedia.org/wiki/Dispersion_(water_waves)http://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Period_(physics)http://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Phase_velocityhttp://en.wikipedia.org/wiki/Waves_and_shallow_water


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Energy planning soft+are

Bollowing are some of the energy planning softwares

4eap

Enpep

Carket power

#ystem optimi+er

4eap

4EA"5 the 4ong range Energy Alternatives "lanning system, is a 'indows$basedsoftware system for energy and environmental policy analysis. %t is widely usedfor integrated energy planning and climate change mitigation analysis and hasbeen applied in hundreds of different organi+ations in over 6/ countries.

4EA" is developed and supported by the


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ar.et po+er

Bollowing are the key benefits of the market power

"erform Conte :arlo simulations around uncertain demand, generator

availability, hydro conditions, fuel prices, and economic conditions Evaluate capacity mothballing, e&pansion, and retirement alternatives

based on economic analysis


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lecture notes energy resources

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