It is the ability to do work. It is the ability to do work.

(1)

ENERGY ENERGY



It is the ability to do work. It is the ability to do work.



In physics, work is done when a force applied In physics, work is done when a force applied to an object which moves it some distance in to an object which moves it some distance in

the direction of the force.



Mathematically, W = Fs, where W is the work Mathematically, W = Fs, where W is the work done, F is the force applied, and s is the

done, F is the force applied, and s is the distance moved.

distance moved.

(2)

DIFFERENT ENERGY SOURCES DIFFERENT ENERGY SOURCES



‘ ‘ Traditional’ fuels such as fuel wood, crop Traditional’ fuels such as fuel wood, crop wastes, and animal dung.(non-commercial) wastes, and animal dung.(non-commercial)



Fossil fuels such as coal, oil and natural gas Fossil fuels such as coal, oil and natural gas (commercial ‘traditional’ fuels)

(commercial ‘traditional’ fuels)



Non-traditional renewable energy sources as Non-traditional renewable energy sources as

hydro, modern biomass, solar, wind, ocean and hydro, modern biomass, solar, wind, ocean and

geothermal.

(3)

ENERGY FORMS ENERGY FORMS



SOLAR SOLAR



WATER WATER



WIND WIND



GEOTHERMAL GEOTHERMAL

(4)

SOLAR ENERGY

(5)

WHAT IS SOLAR ENERGY?

 It is the radiation from the sun that is capable of It is the radiation from the sun that is capable of producing heat, causing chemical reactions, or producing heat, causing chemical reactions, or

generating electricity.

 It is the largest source of energy received on Earth, It is the largest source of energy received on Earth, but its intensity on the earth’s surface is quite low.

but its intensity on the earth’s surface is quite low.

 Solar energy is rapidly becoming the ultimate energy Solar energy is rapidly becoming the ultimate energy source because of its non-polluting character and its source because of its non-polluting character and its

inexhaustible supply which are in stark contrast to inexhaustible supply which are in stark contrast to

such fossil fuel sources as coal, oil, and natural gas.

(6)

COMPOSITION COMPOSITION

 The Sun emits EM radiation across most of the The Sun emits EM radiation across most of the electromagnetic spectrumelectromagnetic spectrum

 The Sun does, however, emit The Sun does, however, emit X-rays, X-rays, ultravioletultraviolet, , visible lightvisible light , , infraredinfrared , and even

, and even Radio waves.When ultraviolet radiation is not absorbed by Radio waves.When ultraviolet radiation is not absorbed by the atmosphere or other protective coating, it can cause damage to the the atmosphere or other protective coating, it can cause damage to the

skin known as

skin known as sunburn or trigger an adaptive change in human sunburn or trigger an adaptive change in human skin pigmentation

skin pigmentation..

(7)

 The sunlight that reaches the ground consists of nearly The sunlight that reaches the ground consists of nearly 50% visible light, 45% infrared radiation, and smaller 50% visible light, 45% infrared radiation, and smaller

amounts of ultraviolet light and other forms of amounts of ultraviolet light and other forms of

electromagnetic radiation.

 This radiation can be converted either into: thermal energy This radiation can be converted either into: thermal energy or into electrical energy.

or into electrical energy.

 Two main types of devices are used to capture solar Two main types of devices are used to capture solar energy and convert it into thermal energy:

energy and convert it into thermal energy:

Flat-plate collectors and Concentrating collectors.

 The flat plate collectors are used for hot water heating and The flat plate collectors are used for hot water heating and house heating.

house heating.

 Concentrating collectors are used when higher Concentrating collectors are used when higher

temperatures are needed. That is, where they reflect and temperatures are needed. That is, where they reflect and

concentrate sunlight from a wide area.

(8)



Solar energy can be converted to Solar energy can be converted to

electricity using photovoltaic cells/ solar electricity using photovoltaic cells/ solar

cells.



This converted energy is used to provide This converted energy is used to provide electricity for watches, calculators and electricity for watches, calculators and

cameras.



Unfortunately, though solar energy is free, Unfortunately, though solar energy is free, the high cost of its collection, conversion the high cost of its collection, conversion

and storage has limited its exploitation.

(9)

GENERATION OF SOLAR GENERATION OF SOLAR

POWER POWER

 Solar powerSolar power is the is the conversion of

conversion of sunlightsunlight into

into electricityelectricity, either , either directly using

directly using photovoltaics

photovoltaics (PV), or (PV), or indirectly using

indirectly using

concentrated solar power concentrated solar power

(CSP).

 Photovoltaics converts Photovoltaics converts light into electric current light into electric current

using the using the

photoelectric effect photoelectric effect..

(10)

Energy storage methods Energy storage methods

 Solar energy can be stored at high Solar energy can be stored at high temperatures using molten salts.

temperatures using molten salts.

Salts are an effective storage Salts are an effective storage

medium because they are low-cost, medium because they are low-cost,

have a high specific heat capacity have a high specific heat capacity

and can deliver heat at and can deliver heat at

temperatures compatible with temperatures compatible with conventional power systems.

conventional power systems.

(11)

SOLAR CELL SOLAR CELL

 A A solar cellsolar cell (also called (also called photovoltaic cellphotovoltaic cell or or photoelectric cell

photoelectric cell) is a ) is a solid statesolid state device that device that converts the energy of

converts the energy of sunlightsunlight directly into directly into electricity

electricity by the by the photovoltaic effectphotovoltaic effect. Assemblies of . Assemblies of cells are used to make

cells are used to make solar modulessolar modules, also known as , also known as solar panels

solar panels. The energy generated from these solar . The energy generated from these solar modules, referred to as

modules, referred to as solar powersolar power, is an example of , is an example of solar energy

solar energy..

 Cells are described as Cells are described as photovoltaic cellsphotovoltaic cells when the when the light source is not necessarily sunlight. These are light source is not necessarily sunlight. These are

used for detecting light or other used for detecting light or other

electromagnetic radiation

electromagnetic radiation near the visible range, for near the visible range, for example

example infrared detectorsinfrared detectors, or measurement of light , or measurement of light intensity.

intensity.

(12)

SOLAR CELL SOLAR CELL

Solar modules/panels

A basic structure of a typical solar cell

(13)

 Solar technologies are broadly characterized as either Solar technologies are broadly characterized as either passive solar

passive solar or or active solaractive solar depending on the way depending on the way they capture, convert and distribute solar energy.

they capture, convert and distribute solar energy.

 Active solar techniques include the use of Active solar techniques include the use of photovoltaic panels and

photovoltaic panels and solar thermalsolar thermal collectors to collectors to harness the energy.

harness the energy.

 Passive solar techniques include orienting a building Passive solar techniques include orienting a building to the Sun, selecting materials with favorable

to the Sun, selecting materials with favorable thermal mass

thermal mass or light dispersing properties, and or light dispersing properties, and designing spaces that

designing spaces that naturally circulate airnaturally circulate air..

 Active solar technologies increase the supply of Active solar technologies increase the supply of energy and are considered

energy and are considered supply sidesupply side technologies, technologies, while passive solar technologies reduce the need for while passive solar technologies reduce the need for

alternate resources and are generally considered alternate resources and are generally considered

demand side technologies.

(14)

APPLICATIONS OF SOLAR APPLICATIONS OF SOLAR

ENERGY ENERGY



A partial list of solar applications includes A partial list of solar applications includes space heating and cooling through

space heating and cooling through solar architecture

solar architecture , , potable water potable water via via distillation distillation and and disinfection disinfection , , daylighting daylighting , , solar hot water solar hot water , ,

solar cooking

solar cooking , and high temperature process , and high temperature process heat for industrial purposes.

heat for industrial purposes.



To harvest the solar energy, the most common To harvest the solar energy, the most common way is to use

way is to use solar panels solar panels . .

(15)

Agriculture

Agriculture and and horticulture horticulture

 AgricultureAgriculture and and horticulturehorticulture seek to optimize seek to optimize the capture of solar energy in order to optimize the capture of solar energy in order to optimize

the productivity of plants.

 Applications of solar energy in agriculture Applications of solar energy in agriculture aside from growing crops include pumping aside from growing crops include pumping

water, drying crops, brooding chicks and water, drying crops, brooding chicks and

drying chicken manure drying chicken manure

 More recently the technology has been More recently the technology has been embraced by vinters, who use the energy embraced by vinters, who use the energy generated by solar panels to power grape generated by solar panels to power grape

presses.

 GreenhousesGreenhouses convert solar light to heat, convert solar light to heat,

enabling year-round production and the growth enabling year-round production and the growth

(in enclosed environments) of specialty crops (in enclosed environments) of specialty crops

and other plants not naturally suited to the and other plants not naturally suited to the

local climate.

(16)

Solar lighting Solar lighting

 DaylightingDaylighting systems collect and systems collect and distribute sunlight to provide distribute sunlight to provide

interior illumination.

 Hybrid solar lightingHybrid solar lighting is an is an active solar

active solar method of providing method of providing interior illumination.

interior illumination.

 Solar thermal technologies can Solar thermal technologies can be used for water heating, space be used for water heating, space

heating, space cooling and heating, space cooling and

process heat generation process heat generation

 Solar hot water systems use Solar hot water systems use

(17)

Water treatment Water treatment

 Solar distillation can be used to Solar distillation can be used to make

make salinesaline or or brackish waterbrackish water potable

potable

 Solar water Solar water disinfectiondisinfection (SODIS) (SODIS) involves exposing water-filled involves exposing water-filled

plastic

plastic polyethylene terephthalatepolyethylene terephthalate (PET) bottles to sunlight for

(PET) bottles to sunlight for several hours

several hours

 It is recommended by the It is recommended by the World Health Organization

World Health Organization as a as a viable method for household viable method for household

water treatment and safe storage water treatment and safe storage

 Solar energy may be used in a Solar energy may be used in a water stabilisation pond to treat water stabilisation pond to treat

waste water

waste water without chemicals or without chemicals or electricity.

electricity.

Solar water heater

(18)

Cooking Cooking

 Solar cookers use sunlight for Solar cookers use sunlight for cooking, drying and

cooking, drying and pasteurizationpasteurization. . They can be grouped into three broad They can be grouped into three broad

categories: box cookers, panel categories: box cookers, panel

cookers and reflector cookers cookers and reflector cookers

 A basic box cooker consists of an A basic box cooker consists of an

insulated container with a transparent insulated container with a transparent

lid.

 Panel cookers use a reflective panel Panel cookers use a reflective panel to direct sunlight onto an insulated to direct sunlight onto an insulated

container and reach temperatures container and reach temperatures

comparable to box cookers.

 Reflector cookers use various Reflector cookers use various concentrating geometries (dish, concentrating geometries (dish,

trough, Fresnel mirrors) to focus trough, Fresnel mirrors) to focus

light on a cooking container.

(19)

Process heat Process heat

 Solar concentrating Solar concentrating technologies such as technologies such as

parabolic dish, trough and parabolic dish, trough and

Scheffler reflectors can Scheffler reflectors can provide process heat for provide process heat for

commercial and industrial commercial and industrial

applications.

 Evaporation ponds are Evaporation ponds are shallow pools that

shallow pools that

concentrate dissolved solids concentrate dissolved solids

through

through evaporationevaporation. .

 Clothes linesClothes lines, clotheshorses, clotheshorses, , and clothes racks dry clothes and clothes racks dry clothes through evaporation by wind through evaporation by wind

and sunlight without and sunlight without

consuming electricity or gas.

STEP parabolic dishes used for steam production and electrical generation.

(20)

Electrical generation Electrical generation

(solar power) (solar power)

 Solar power is the Solar power is the

conversion of sunlight into conversion of sunlight into

electricity

electricity, either directly , either directly using

using photovoltaicsphotovoltaics (PV), (PV), or indirectly using

or indirectly using

concentrated solar power concentrated solar power (CSP). CSP systems use (CSP). CSP systems use

lenses or mirrors and lenses or mirrors and

tracking systems to focus a tracking systems to focus a large area of sunlight into a large area of sunlight into a

small beam. PV converts small beam. PV converts light into electric current light into electric current

using the using the

(21)

Experimental solar power Experimental solar power

 A A solar pondsolar pond is a pool of salt water (usually 1–2 is a pool of salt water (usually 1–2 mm deep) that collects and stores solar energy.

deep) that collects and stores solar energy.

 The pond consisted of layers of water that The pond consisted of layers of water that

successively increased from a weak salt solution at successively increased from a weak salt solution at

the top to a

the top to a high salthigh salt solution at the bottom. solution at the bottom.

 This solar pond was capable of producing This solar pond was capable of producing

temperatures of 90 °C in its bottom layer and had an temperatures of 90 °C in its bottom layer and had an estimated solar-to-electric efficiency of two percent.

estimated solar-to-electric efficiency of two percent.

 ThermoelectricThermoelectric, or "thermovoltaic" devices convert a , or "thermovoltaic" devices convert a temperature difference between dissimilar materials temperature difference between dissimilar materials

into an electric current.

(22)

Solar chemical Solar chemical

 Solar chemical processes use solar energy to drive Solar chemical processes use solar energy to drive

chemical reactions. These processes offset energy that chemical reactions. These processes offset energy that

would otherwise come from an alternate source and can would otherwise come from an alternate source and can

convert solar energy into storable and transportable fuels.

Solar induced chemical reactions can be divided into Solar induced chemical reactions can be divided into

thermochemical or

thermochemical or photochemicalphotochemical

 Hydrogen productionHydrogen production technologies been a significant area technologies been a significant area of solar chemical research since the 1970s.

of solar chemical research since the 1970s.

 Another approach uses the heat from solar concentrators Another approach uses the heat from solar concentrators to drive the

to drive the steam reformationsteam reformation of natural gas thereby of natural gas thereby increasing the overall hydrogen yield compared to increasing the overall hydrogen yield compared to

conventional reforming methods conventional reforming methods

 Thermochemical cycles characterized by the Thermochemical cycles characterized by the

decomposition and regeneration of reactants present decomposition and regeneration of reactants present

(23)

Solar vehicles Solar vehicles

 Some vehicles use solar Some vehicles use solar panels for auxiliary power, panels for auxiliary power,

such as for air such as for air

conditioning, to keep the conditioning, to keep the

interior cool, thus reducing interior cool, thus reducing

fuel consumption fuel consumption

 A A solar balloonsolar balloon is a black is a black balloon that is filled with balloon that is filled with

ordinary air.

 Solar sailsSolar sails are a proposed are a proposed form of spacecraft

form of spacecraft

propulsion using large propulsion using large

membrane mirrors to membrane mirrors to

exploit radiation pressure exploit radiation pressure

from the Sun.

(24)

SOLAR ENERGY PROS SOLAR ENERGY PROS

 Solar panels give off no pollutionSolar panels give off no pollution

 Solar energy produces electricity very quietly.Solar energy produces electricity very quietly.

 It has the ability to harness electricity in remote It has the ability to harness electricity in remote locations that are not linked to a national grid.

locations that are not linked to a national grid.

 Very efficient in large areas of the globe.Very efficient in large areas of the globe.

 Solar panels can be installed on top of many rooftopsSolar panels can be installed on top of many rooftops

 It is affordable in the long run. It is affordable in the long run.

 The use of solar energy to produce electricity allows The use of solar energy to produce electricity allows the user to become less dependent on the worlds fossil the user to become less dependent on the worlds fossil

fuel supplies.

(25)

SOLAR ENERGY CONS SOLAR ENERGY CONS

 The major con of solar energy is the initial cost of The major con of solar energy is the initial cost of solar cells.

solar cells.

 Solar energy is only able to generate electricity during Solar energy is only able to generate electricity during daylight hours. This means for around half of each

daylight hours. This means for around half of each day, solar panels are not producing energy for your day, solar panels are not producing energy for your

home.

 The weather can affect the efficiency of solar cells.The weather can affect the efficiency of solar cells.

 Pollution can be a con of solar energy, as pollution Pollution can be a con of solar energy, as pollution

levels can affect a solar cells efficiency, this would be levels can affect a solar cells efficiency, this would be

a major con for businesses or industry wishing to a major con for businesses or industry wishing to

install solar panels in heavily polluted areas, such as install solar panels in heavily polluted areas, such as

cities.

(26)

Environmental Effects of Solar Environmental Effects of Solar

Energy Energy

 Carbon EmissionsCarbon Emissions

 Renewable EnergyRenewable Energy

 Abundant ComponentsAbundant Components

 CadmiumCadmium

 Space ConsiderationsSpace Considerations

(27)

MEDICAL USES OF SOLAR MEDICAL USES OF SOLAR

ENERGY ENERGY

 These include, disinfection and sterilization without the use of chemicals. Ultraviolet light is also used to destroy bacteria and viruses.

• It stimulates the immune system and has shown good results in killing blood borne pathogens.

• Some microorganisms destroyed by ultraviolet light are bacillus anthracis, salmonella or food poisoning, shigella dysentariae or dysentery, bacteriophage or E. coli, hepatitis and influenza.

 Ultraviolet light can be combined with other Ultraviolet light can be combined with other therapies.

therapies.

 Some kinds of skin conditions can improve with the Some kinds of skin conditions can improve with the exposure of ultraviolet light.

exposure of ultraviolet light.

(28)

Solar Energy Health Effects on Solar Energy Health Effects on

Humans Humans



These are: These are:

 Electromagnetic Radiation From Solar Electromagnetic Radiation From Solar Panels

Panels

 Silicon Dust from Solar PanelsSilicon Dust from Solar Panels

 Exposure to Electrical and Chemical Exposure to Electrical and Chemical Components of Solar Heat Systems Components of Solar Heat Systems

 The Future of Solar EnergyThe Future of Solar Energy

(29)



The body produces The body produces vitamin D vitamin D from sunlight from sunlight (specifically from the UVB band of

(specifically from the UVB band of ultraviolet ultraviolet light), and excessive seclusion from the sun light), and excessive seclusion from the sun

can lead to deficiency unless adequate can lead to deficiency unless adequate

amounts are obtained through diet.



On the other hand, excessive sunlight exposure On the other hand, excessive sunlight exposure has been linked to all types of

has been linked to all types of skin cancer skin cancer caused by the

caused by the ultraviolet ultraviolet part of radiation from part of radiation from sunlight or sunlamps

sunlight or sunlamps

(30)



A lack of sunlight, on the other hand, is A lack of sunlight, on the other hand, is considered one of the primary causes of considered one of the primary causes of

seasonal affective disorder

seasonal affective disorder (SAD), a serious (SAD), a serious form of the "winter blues". SAD occurrence is form of the "winter blues". SAD occurrence is

more prevalent in locations further from the more prevalent in locations further from the

tropics, and most of the treatments (other than tropics, and most of the treatments (other than

prescription drugs) involve

prescription drugs) involve light therapy light therapy



A recent study indicates that more exposure to A recent study indicates that more exposure to sunshine early in a person’s life relates to less sunshine early in a person’s life relates to less

risk from

risk from multiple sclerosis multiple sclerosis (MS) later in life (MS) later in life

(31)

SOLAR ENERGY AND GUYANA SOLAR ENERGY AND GUYANA

 Solar energy is primarily being installed in the Solar energy is primarily being installed in the

hinterland/remote areas of the country. Currently under the hinterland/remote areas of the country. Currently under the

Unserved Areas Electrification Programme, a number of Unserved Areas Electrification Programme, a number of

communities have received solar photovoltaic’s home communities have received solar photovoltaic’s home

systems.

 Solar power will provide lights, entertainment & emergency Solar power will provide lights, entertainment & emergency communication for 100 persons in Wayling.

communication for 100 persons in Wayling.

 ““Solar energy systems have been tested/validated in several Solar energy systems have been tested/validated in several hinterland communities. Combined with appropriate learning hinterland communities. Combined with appropriate learning

tools these small systems can revolutionize Guyana’s rural tools these small systems can revolutionize Guyana’s rural

educational system.”

- - Edward Jarvis, Field Coordinator, Ministry of EducationEdward Jarvis, Field Coordinator, Ministry of Education

(32)

REFERENCE REFERENCE

 Ref: Solar energyRef: Solar energy

 From Wikipedia, the free encyclopedia.This page was last modified on 7 March From Wikipedia, the free encyclopedia.This page was last modified on 7 March 2011 at 12:56.Retrieved on 2011-03-07

2011 at 12:56.Retrieved on 2011-03-07http://en.wikipedia.org/wiki/Solar_energyhttp://en.wikipedia.org/wiki/Solar_energy

 Duncan Tom, Onac Deniz- Physics for the Caribbean: John Murray Ltd.: London: Duncan Tom, Onac Deniz- Physics for the Caribbean: John Murray Ltd.: London:

19851985

 Lambert norman, Samuel A. Tricia- Heinemann Physics for CXC: Heinemann Lambert norman, Samuel A. Tricia- Heinemann Physics for CXC: Heinemann Educational Publishers: Oxford:2000.

Educational Publishers: Oxford:2000.

 Rianne Hill Soriano, eHow Contributor Rianne Hill Soriano, eHow Contributor Solar Energy Health Effects on Solar Energy Health Effects on Humans,

Humans,updated: April 02, 2010retrieved on 18-03-2011<updated: April 02, 2010retrieved on 18-03-2011<

Solar Energy Health Effects on Humans | eHow.com Solar Energy Health Effects on Humans | eHow.com

http://www.ehow.com/list_6155201_solar-energy-health-effects-humans.html#ixzz1Gov4MiqR http://www.ehow.com/list_6155201_solar-energy-health-effects-humans.html#ixzz1Gov4MiqR

>>

 Sherry Barnhart, eHow Contributor ,Sherry Barnhart, eHow Contributor ,

Medical Use of Ultraviolet Lights | eHow.com Medical Use of Ultraviolet Lights | eHow.com

http://www.ehow.com/about_5185794_medical-use-ultraviolet-lights.html#ixzz1Goy9gjng http://www.ehow.com/about_5185794_medical-use-ultraviolet-lights.html#ixzz1Goy9gjng

(33)