Solar energy is the most readily available source of energy. It does not belong to anybody and is, therefore, free. It is also the most important of the non-conventional sources of energy because it is non-polluting and, therefore, helps in lessening the greenhouse effect.
Solar energy has been used since prehistoric times, but in a most primitive manner. Before 1970, some research and development was carried out in a few countries to exploit solar energy more efficiently, but most of this work remained mainly academic. After the dramatic rise in oil prices in the 1970s, several countries began to formulate extensive research and development programmes to exploit solar energy.
When we hang out our clothes to dry in the sun, we use the energy of the sun. In the same way, solar panels absorb the energy of the sun to provide heat for cooking and for heating water. Such systems are available in the market and are being used in homes and factories.
In the next few years it is expected that millions of households in the world will be using solar energy as the trends in USA and Japan show. In India too, the Indian Renewable Energy Development Agency and the Ministry of Non-Conventional Energy Sources are formulating a programme to have solar energy in more than a million households in the next few years. However, the people’s initiative is essential if the programme is to be successful.
India is one of the few countries with long days and plenty of sunshine, especially in the Thar desert region. This zone, having abundant solar energy available, is suitable for harnessing solar energy for a number of applications. In areas with similar intensity of solar radiation, solar energy could be easily harnessed. Solar thermal energy is being used in India for heating water for both industrial and domestic purposes. A 140 MW integrated solar power plant is to be set up in Jodhpur but the initial expense incurred is still very high.
Solar energy can also be used to meet our electricity requirements. Through Solar Photovoltaic (SPV) cells, solar radiation gets converted into DC electricity directly. This electricity can either be used as it is or can be stored in the battery. This stored electrical energy then can be used at night. SPV can be used for a number of applications such as:
a. domestic lighting
b. street lighting
c. village electrification
d. water pumping
e. desalination of salty water
f. powering of remote telecommunication repeater stations and
g. railway signals.
Sunday, June 6, 2010
Energy changes from one Form to Another
Solar Energy is the energy from the Sun. The Sun is a big ball of heat and light resulting from nuclear fusion at its core. The nuclear reaction releases energy that travels outward to the surface of the Sun. Along the way to the surface the energy transforms so that by the time it is released it is primarily light energy. Sunlight. The two major types of solar energy that make it to Earth are heat and light.
Solar energy is often called "alternative energy" to fossil fuel energy sources such as oil and coal.
One example of our use of solar heat energy is for water heating systems. A solar panel is used to collect heat. The heat is transferred to pipes inside the solar panel and water is heated as it passes through the pipes. The hot water, heated by the Sun, can then be used for showers, cleaning, or heating your home.
We also use solar thermal energy through passive solar designs. Windows or skylights in your home can be designed to face the Sun so that they let heat into the house, keeping you warmer in the winter.
The light energy from the Sun can be transformed into electrical energy and used immediately or stored in batteries. Photovoltaic (PV) panels are the devices that convert light energy into electrical energy.
Let's look at a solar powered vehicle that runs on electricity directly from solar energy as a simple example in the transformation of energy from one form to another.
Sunlight hits the PV panel and the panel transforms the light energy into electrical energy.
The electrical energy (electricity) passes through the wire circuit to the motor.
The motor transforms the electrical energy into mechanical energy to turn the drive shaft which turns the wheels.
The wheels rotate on the ground to move the vehicle transforming mechanical energy into vehicle motion (kinetic energy).
Solar Vehicle Ideal Energy Chain:
Light Energy >> Electrical Energy >> Mechanical Energy >> Kinetic Energy
Solar energy is often called "alternative energy" to fossil fuel energy sources such as oil and coal.
One example of our use of solar heat energy is for water heating systems. A solar panel is used to collect heat. The heat is transferred to pipes inside the solar panel and water is heated as it passes through the pipes. The hot water, heated by the Sun, can then be used for showers, cleaning, or heating your home.
We also use solar thermal energy through passive solar designs. Windows or skylights in your home can be designed to face the Sun so that they let heat into the house, keeping you warmer in the winter.
The light energy from the Sun can be transformed into electrical energy and used immediately or stored in batteries. Photovoltaic (PV) panels are the devices that convert light energy into electrical energy.
Let's look at a solar powered vehicle that runs on electricity directly from solar energy as a simple example in the transformation of energy from one form to another.
Sunlight hits the PV panel and the panel transforms the light energy into electrical energy.
The electrical energy (electricity) passes through the wire circuit to the motor.
The motor transforms the electrical energy into mechanical energy to turn the drive shaft which turns the wheels.
The wheels rotate on the ground to move the vehicle transforming mechanical energy into vehicle motion (kinetic energy).
Solar Vehicle Ideal Energy Chain:
Light Energy >> Electrical Energy >> Mechanical Energy >> Kinetic Energy
Solar Energy, Power, Electricity
Basic about Solar Energy, Solar Power and Solar Electricity.
In basic about solar energy, solar power and solar eletricity we will talk about the basic things behind this power. Formulas that will be used to find out which Solar Panel you should use and which battery you should select. And how much Solar Panels do you need to power up lights and other applications. Here are the main things you need to know and that will be used to calculate your needs. AC-DC system, Volt, Current(Ampere), Power(Watt), Resistance, Series and Parallel connecting.
AC-DC system
Ac stands for Alternative Current. Alternative current is almost that we found in wall outlet or electric outlet. Clever say'd that we found in wall. It is 230 Volt. DC stands for Direct Current. In solar panels it is used 12 volt dc system. DC is that current we can found in cells, batteries, and using adapters or regulators. See the picture of a dell charger. Dell charger also converts AC Current to DC 5.4 Volt and 2410mA. Solar Panels also uses DC voltage and Current.
Volt
Voltage is the electromotive force (pressure) applied to an electrical circuit measured in volts (E).
Example. P=200W, I=4.0A. If we have a value of watt and ampere and we want to find out how much volt does it use then we should use this from Power Circle. E=P/I. 200/4.0=50V. So we found voltage is 50V.
Current
Current is the flow of electrons in an electrical circuit measured in amperes (I).
Example. P=100W, E=12V. We want to find out how much ampere does it use. We take a look at circle. I=P/E. 100/12=8.33A. Current usage is 8.33A.
Power
Power is the product of the voltage times the current in an electrical circuit measured in watts (P).
Example. E=220V, I=0,4A. This example is taken from picture of Dell Charger. We have 400mA=0,4A. Take a look at circle P=E*I. 220V * 0,4A=88W. Answer is dell charger use 88Watt.
Resistance
Resistance is the opposition to the flow of electrons in an electrical circuit measured in ohms (R). Increased resistance gives higher voltage and higher power(watt).
Example. E=12V, I=3.0A. We want to find out resistance. We use formula R=E/I. 12V/3.0A = 4 Ohm.
Parallel Connecting - 12V System
Parallel Connecting solar panels gives higher current. And voltage will remain the same. Parallel Connecting is best for us. Because we do not need high voltage. Normal battery is 12v. And by selecting high voltage require higher voltage charge controller. To connect solar panels in parallel we have to connect plus + to plus and minus - to minus.
Series Connecting - 24V System
By connecting Solar Panels in series connection. It will increase Voltage and current Amps. will remain the same. To connect solar panels in series we have to connect plus + to - minus on next panel. See the picture for details. In this example we have connected 2 solar panels in series which will give 24v output.
Solar energy changing lives in remote,backward Tharparkar region
Environment-friendly solar energy has changed the lives of several hundred households in Tharparkar, which remains one of the most backward regions of the country.
The Alternate Energy Development Board, Pakistan Poverty Alleviation Fund and Thardeep Rural Development Programme ñ a non-governmental organisation ñ have joined hands to launch the solar energy project in this arid region at a time when the country faces massive electricity shortage.
In a vast desert region like Tharparkar, where temperature hit a peak of 30-35 degrees Celsius even in winters and touches a high of over 50 degrees Celsius during summers, the scorching rays of sun are usually seen as a bane.
But for the first time, this immeasurable resource is being utilised like any other modern place of the world.
Solar energy is not just providing electricity to the mud-and-straw houses of remote villages, but also helps irrigate small patches of land.
“The electricity has changed our lives,” said Khanno, a 45-year-old farmer, who like most residents of this place uses only one name. “Electricity has extended our day. Now my children can study even after the sunset.”
The solar energy project, launched two years ago, has so far provided electricity to 16 villages at a cost of more than Rs100 million, including the villages of Kasbo, Rarko, Wadhanjowadhio and Oanjowadhio ñ all in Tharparkar district.
Riaz Rajar, an official of Thardeep Rural Development Programme, said that one panel costs around Rs700,000 to Rs800,000.
"We install at least eight such panels in a village, which is a one time investment," he said. "They generate enough electricity to illuminate 20 to 30 houses."
“Pakistan Poverty Alleviation Fund contributes 80 per cent of the funds and the remaining 20 per cent is raised by the local community,” Rajar said.
He said that electricity-run power pumps help pull water from 50 to 150 feet below the surface.
“Apart from drinking, this water is also used for irrigation through drip technique to save wastage and conserve this precious natural resource, which is scarce in this region.”
Scarcity of water in Tharparkar, bordering the Great Indian Desert, impacts the entire population, especially women, who had to walk miles to fetch two buckets of water from the wells.
But electric pumps have made their life easy.
Now solar energy is being used to pull water, which is stored in cement tanks.
Khanno, the farmer, said that thanks to electricity he now manages to cultivate onions and tomatoes on his two acres of once barren land.
According to SciDev, a London-based non-profit organisation, there is no shortage of solar energy across the world. Almost all the developing countries have enormous solar power potential, it said in a report.
The Alternate Energy Development Board, Pakistan Poverty Alleviation Fund and Thardeep Rural Development Programme ñ a non-governmental organisation ñ have joined hands to launch the solar energy project in this arid region at a time when the country faces massive electricity shortage.
In a vast desert region like Tharparkar, where temperature hit a peak of 30-35 degrees Celsius even in winters and touches a high of over 50 degrees Celsius during summers, the scorching rays of sun are usually seen as a bane.
But for the first time, this immeasurable resource is being utilised like any other modern place of the world.
Solar energy is not just providing electricity to the mud-and-straw houses of remote villages, but also helps irrigate small patches of land.
“The electricity has changed our lives,” said Khanno, a 45-year-old farmer, who like most residents of this place uses only one name. “Electricity has extended our day. Now my children can study even after the sunset.”
The solar energy project, launched two years ago, has so far provided electricity to 16 villages at a cost of more than Rs100 million, including the villages of Kasbo, Rarko, Wadhanjowadhio and Oanjowadhio ñ all in Tharparkar district.
Riaz Rajar, an official of Thardeep Rural Development Programme, said that one panel costs around Rs700,000 to Rs800,000.
"We install at least eight such panels in a village, which is a one time investment," he said. "They generate enough electricity to illuminate 20 to 30 houses."
“Pakistan Poverty Alleviation Fund contributes 80 per cent of the funds and the remaining 20 per cent is raised by the local community,” Rajar said.
He said that electricity-run power pumps help pull water from 50 to 150 feet below the surface.
“Apart from drinking, this water is also used for irrigation through drip technique to save wastage and conserve this precious natural resource, which is scarce in this region.”
Scarcity of water in Tharparkar, bordering the Great Indian Desert, impacts the entire population, especially women, who had to walk miles to fetch two buckets of water from the wells.
But electric pumps have made their life easy.
Now solar energy is being used to pull water, which is stored in cement tanks.
Khanno, the farmer, said that thanks to electricity he now manages to cultivate onions and tomatoes on his two acres of once barren land.
According to SciDev, a London-based non-profit organisation, there is no shortage of solar energy across the world. Almost all the developing countries have enormous solar power potential, it said in a report.
Solar-energy plane passes first flight test
There has never been in the past an aeroplane of that kind to fly. It was a huge question mark for us and it's an extraordinary relief,” said Bertrand Piccard, pioneering round-the-world balloonist who co-founded the project.
“Today for Solar Impulse it's an incredible milestone. It gives us confidence for the next flight and for the next missions,” he added.
The high tech prototype had lifted off into blue skies at a speed of just 45 kilometres per hour (28 miles per hour) after running a few hundred metres down the runway at Payerne air base shortly before 10:30 am.
Propelled by four 10 horsepower electric motors, the gangling single-seater aircraft and test pilot Markus Scherdel slowly gained altitude until 1,200 metres.
After 87 minutes, the plane descended gracefully back to land.
“Everything worked as it should. The flight was very successful. We were able to fly the programme as planned and we are safe on the ground again,” said Scherdel.
Following Wednesday's test, the 70-strong team which had worked seven years on the project is expecting to carry out other test flights to refine the prototype aircraft.
Organisers added that the team will also construct the actual plane that would undertake the world tour in five stages by 2013, and not 2012 as previously announced.
“We will continue test flights to improve the design of the second plane that would go around the world,” said Andre Borschberg, a co-founder of the project, adding that construction on the aircraft would start next year.
“This summer, we want to show that we can fly night and day. This will happen in Payerne. Hopefully in May, June or July,” he added.
The prototype, which is slightly smaller than the plane that will undertake the round-the-world flight, has a wingspan comparable to that of an Airbus A340 airliner but weighs as little as a family-sized car at only 1,600 kilogrammes (3,527 pounds).
Borschberg said the first test flight was primarily aimed at testing the complex aircraft's behaviour in the air.
“The success of this first flight allows us to envisage the further programme with greater serenity,” he said.
The Solar Impulse prototype had briefly taken off for the first time in December for a controlled 400-metre hop about one metre above the runway, but a full flight had been delayed for weeks until weather conditions improved.
The aircraft's slender long wings are covered with about 12,000 solar cells that fuel its 400 kilogramme battery packs and the electric motors.
The tests are due to build up to a first non-stop 36-hour flight through darkness by the summer, followed by a five-stage flight around the world in 2013.
What Is Solar Energy?
Plants have been using the energy from the sun for billions of years. Until recently, however, this energy has been available only indirectly to humans via the energy we harvest in the form of everything from fossil fuels to plants to wind power (all solar energy derivatives).
Today, as environmental awareness and rising oil prices put pressure on society, the potential of emerging solar energy technologies that directly harness the nearly limitless energy of the sun is increasingly desirable and economically feasible.
Harnessing Solar Energy
Harnessing solar energy involves both the direct use of the radiated heat as well as its conversion to electricity in the most efficient way possible. There are three categories that define every type of solar energy technology.
First, passive solar collection begins with the design of the building and includes optimal location, windows facing south, walls that absorb heat and light, and plenty of insulation. The heat and light that is collected is used in its original form of heat or light such as in a greenhouse. For example, the chapel on the Massachusetts Institute of Technology campus has no windows, but has been designed such that natural light reflects off the surrounding moat and into the room. Passive collection is much easier to include in new construction because retrofitting an existing building can be difficult and costly. Active solar collection implies converting solar energy to a more usable form of heat or electricity.
A second distinction is the type of energy an active solar system creates. Thermal applications include heat collection and heat-driven mechanisms, such as converting water to steam to power a steam engine that generates electricity. Electric processes use photovoltaic cells that create a moving electric charge that produces a direct electric current. PV panels have been used successfully on satellites and have a life expectancy of thirty years, making them an economically viable option for commercial use.
Finally, a third distinction in solar energy concerns the degree of concentration used in harnessing the suns energy. Concentrating systems engage mirrors and lenses to direct the sunlight to the area of collection. In some systems, parabolic trough-shaped structures of photovoltaic cells can even be powered to follow the motion of the sun allow for increased electricity generation. Non-concentrating systems are often simple flat panel collectors that are most commonly found as rooftop PV or as solar pool heaters.
The Solar Electricity Industry
In 2005, the amount of electricity generated by photovoltaic systems increased by 56% and resulted in 1,445 megawatts (MW) of PV being installed in the United States, Germany, Japan, among others. At the average of $8.00 per watt, this is a worldwide $12 billion investment in the solar energy markets in 2005 alone. Due to this market growth and increased capital for research and development, production costs for solar electricity are decreasing by five to seven percent per year.
Japan and Germany support the two largest solar markets due to targeted government subsidies designed to stimulate their growth. Japanese companies produced 47% of the PV cells manufactured globally in 2005, while Germany represented half of the installations. The US, once a leader in this technology represented less than 10% of both production and installations globally in 2005.
Worldwide, solar currently provides less than one percent of electricity demand but is projected to supply 26% of the worlds consumption by 2040. This industrial transition will occur as solar generated electricity becomes cost effective throughout the United States and much of the world.
Advantages of Solar Energy
Solar energy enjoys many environmental and economic advantages over other forms of energy currently used. These include:
Environmentally Friendly
Non-polluting: Solar electricity generation produces no emissions while the current alternative, fossil fuel combustion, releases more than a pound of carbon dioxide emissions for every kilowatt hour.
Non-consumptive: The suns radiation is a limitless resource that can be collected without the environmentally destructive processes of mining or pipelines.
Economically Beneficial
Cost effective: Solar generated electricity is already cheaper than conventional electricity in many major US cities. By 2027, PV will be the most cost-effective solution (even without any government subsidies or advantages from its environmental cleanliness) in nearly all areas of the United States.
Immediate and permanent savings: Properly financed systems will provide consumers with cheaper electricity from the day of installation.
Technological advancements: Improvements in solar technologies offer reduced costs and greater efficiency.
Easily Accessible
Security: The price of solar electricity does not fluctuate with politics or supply speculation; there will never be a shortage that will cause solar electricity to become unaffordable.
Already distributed: There are no expensive transportation costs for solar electricity because the sun shines everywhere.
Leapfrogging: Solar electricity will allow sun-rich developing nations to leapfrog as they are doing with wireless telecommunications to a new energy architecture without having to install expensive land-based grids
Today, as environmental awareness and rising oil prices put pressure on society, the potential of emerging solar energy technologies that directly harness the nearly limitless energy of the sun is increasingly desirable and economically feasible.
Harnessing Solar Energy
Harnessing solar energy involves both the direct use of the radiated heat as well as its conversion to electricity in the most efficient way possible. There are three categories that define every type of solar energy technology.
First, passive solar collection begins with the design of the building and includes optimal location, windows facing south, walls that absorb heat and light, and plenty of insulation. The heat and light that is collected is used in its original form of heat or light such as in a greenhouse. For example, the chapel on the Massachusetts Institute of Technology campus has no windows, but has been designed such that natural light reflects off the surrounding moat and into the room. Passive collection is much easier to include in new construction because retrofitting an existing building can be difficult and costly. Active solar collection implies converting solar energy to a more usable form of heat or electricity.
A second distinction is the type of energy an active solar system creates. Thermal applications include heat collection and heat-driven mechanisms, such as converting water to steam to power a steam engine that generates electricity. Electric processes use photovoltaic cells that create a moving electric charge that produces a direct electric current. PV panels have been used successfully on satellites and have a life expectancy of thirty years, making them an economically viable option for commercial use.
Finally, a third distinction in solar energy concerns the degree of concentration used in harnessing the suns energy. Concentrating systems engage mirrors and lenses to direct the sunlight to the area of collection. In some systems, parabolic trough-shaped structures of photovoltaic cells can even be powered to follow the motion of the sun allow for increased electricity generation. Non-concentrating systems are often simple flat panel collectors that are most commonly found as rooftop PV or as solar pool heaters.
The Solar Electricity Industry
In 2005, the amount of electricity generated by photovoltaic systems increased by 56% and resulted in 1,445 megawatts (MW) of PV being installed in the United States, Germany, Japan, among others. At the average of $8.00 per watt, this is a worldwide $12 billion investment in the solar energy markets in 2005 alone. Due to this market growth and increased capital for research and development, production costs for solar electricity are decreasing by five to seven percent per year.
Japan and Germany support the two largest solar markets due to targeted government subsidies designed to stimulate their growth. Japanese companies produced 47% of the PV cells manufactured globally in 2005, while Germany represented half of the installations. The US, once a leader in this technology represented less than 10% of both production and installations globally in 2005.
Worldwide, solar currently provides less than one percent of electricity demand but is projected to supply 26% of the worlds consumption by 2040. This industrial transition will occur as solar generated electricity becomes cost effective throughout the United States and much of the world.
Advantages of Solar Energy
Solar energy enjoys many environmental and economic advantages over other forms of energy currently used. These include:
Environmentally Friendly
Non-polluting: Solar electricity generation produces no emissions while the current alternative, fossil fuel combustion, releases more than a pound of carbon dioxide emissions for every kilowatt hour.
Non-consumptive: The suns radiation is a limitless resource that can be collected without the environmentally destructive processes of mining or pipelines.
Economically Beneficial
Cost effective: Solar generated electricity is already cheaper than conventional electricity in many major US cities. By 2027, PV will be the most cost-effective solution (even without any government subsidies or advantages from its environmental cleanliness) in nearly all areas of the United States.
Immediate and permanent savings: Properly financed systems will provide consumers with cheaper electricity from the day of installation.
Technological advancements: Improvements in solar technologies offer reduced costs and greater efficiency.
Easily Accessible
Security: The price of solar electricity does not fluctuate with politics or supply speculation; there will never be a shortage that will cause solar electricity to become unaffordable.
Already distributed: There are no expensive transportation costs for solar electricity because the sun shines everywhere.
Leapfrogging: Solar electricity will allow sun-rich developing nations to leapfrog as they are doing with wireless telecommunications to a new energy architecture without having to install expensive land-based grids
Which Renewable to Power Your House?
Prices have decreased by about a third over the last year because there are so many suppliers now. Chinese solar panel manufacturers have multiplied tenfold over the last year and many are already meeting European standards.
Two years ago, potential buyers would have to ask suppliers if and how many solar panels they might be able to buy. The manufacturers could pretty much set the prices. Now we have a surplus of solar panels.
t’s a good investment for pretty much everyone in Germany--apart from people living in the northwest--because people here produce electricity not for their own consumption needs but for the grid.
The government guarantees a fixed price for solar power that is much higher than what you pay for electricity from non-regenerative sources. Home owners in Germany aren’t interested in energy independence, but selling at a good price.
Many European countries now have similar feed-in tariffs. In southern Europe and northern Africa it also makes sense to use solar for home consumption. And the U.S. is now starting to deploy solar panels on a large scale. California is already a global leader.
We think that on a global scale grid parity could be achieved by 2015, especially in regions with high electricity prices and lots of sun. Solar power should then be able to hold its own without subsidies, even against electricity from natural gas or nuclear power.
In Germany, you should invest before the end of 2010. Electricity from solar panels built before 2011 can be sold at a guaranteed price that will remain stable for 20 years. After that, the guaranteed price will decrease every year.
But there is an interesting paradox. Solar panels are usually more expensive in countries with a lot of sun, because profits would be much higher here otherwise. Even in Germany, solar panels are more expensive in the sunnier south than in the north.
Two years ago, potential buyers would have to ask suppliers if and how many solar panels they might be able to buy. The manufacturers could pretty much set the prices. Now we have a surplus of solar panels.
t’s a good investment for pretty much everyone in Germany--apart from people living in the northwest--because people here produce electricity not for their own consumption needs but for the grid.
The government guarantees a fixed price for solar power that is much higher than what you pay for electricity from non-regenerative sources. Home owners in Germany aren’t interested in energy independence, but selling at a good price.
Many European countries now have similar feed-in tariffs. In southern Europe and northern Africa it also makes sense to use solar for home consumption. And the U.S. is now starting to deploy solar panels on a large scale. California is already a global leader.
We think that on a global scale grid parity could be achieved by 2015, especially in regions with high electricity prices and lots of sun. Solar power should then be able to hold its own without subsidies, even against electricity from natural gas or nuclear power.
In Germany, you should invest before the end of 2010. Electricity from solar panels built before 2011 can be sold at a guaranteed price that will remain stable for 20 years. After that, the guaranteed price will decrease every year.
But there is an interesting paradox. Solar panels are usually more expensive in countries with a lot of sun, because profits would be much higher here otherwise. Even in Germany, solar panels are more expensive in the sunnier south than in the north.
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