Home Solar Power

There are currently many reasons why a home solar power system can be an important addition to any household.

If you are interested in helping the environment, and the fight against climate change, then you may already be considering the installation of a renewable energy system to your home.

The main advantage of installing a home solar energy system is mainly down to the significant boost you will receive to your electricity supply.

This means your electricity bills will be reduced quite significantly, while the cost of initial installation of a solar energy system will pay itself off over time.

So how can you harness the solar energy in a way that is best suited to your needs? Well you can use solar power panels connected to your home in a number of different ways.

"Why Solar Power and Solar Panels Important"

Importance of Solar Panels

We have ways to heat our water, our homes and provide us with electricity. We probably take all of this for granted and if we lost them we would probably panic. We take for granted that these conveniences will be there for us from now on. We expect glitches to happen but we want them to be fixable without going long without all of these. We appreciate the heat in the winter when it snows outside and when the temperatures drop. We need water to live and although it is usually running under the ground we want the convenience of it running through our pipes and into our homes.

Some people use some of the heat generated from the sun in order to heat homes, power electricity and provide water to their families and businesses. When you think about all that you have that runs through a machine it may be possible to reroute that in order to run it all by sunlight. Scientists have only started to make this possible but it is far from being completed. When you consider all the solar energy that reaches the earth's surface and then radiated back into the atmosphere, you could power electricity, heat and water from now on. This solar energy can be redirected and concentrated using special boxes that attract the light during the day to heat water and homes throughout the night.

Solar panels can be different shapes and sizes but their main purpose is to convert the light in order to make electricity. Photovoltaic, or PV, is the process of converting the light into electricity. Photovoltaic cells are self generating and consist of a very thing film made of silver. This film is placed on a semiconductor layer that can be found on an iron substrate. The photovoltaic cells are very important in producing enough sunlight and heat in order to successfully produce the energy that is needed in order to heat up water, heat homes and power electricity.

solar panels Gardening

Gardening is an American pastime, and interest in it is growing rapidly. People are recognizing how much nice plants and landscaping will help the appearance of their home. It also is an enjoyable hobby to cultivate plants from seed to maturity in your own backyard garden. Adding decorative touches like stepping stones, fountains, or solar garden lighting can show your personal style.

With solar lighting in your garden, you can light a path, or highlight certain plants or features. The best part about it is that it does not need any external power. No chords or anything at all. Just like your plants, it will use the sun's energy to power itself.

A solar garden light is made up of a plastic shell with a solar cell inside. It also has a nickel and cadmium battery, a control board, an LED light source, and a photo resistor.

The sun charges the battery, which powers the solar cell. The control board and the light itself is powered by these. At night, the battery can't charge since the sunlight is gone, so the photo resistor turns on the LED. The LED can run for about 15 hours on a charged battery.

Outdoor electrical wiring can be a hassle to install, especially if your garden is not right next to your home. The solar lighting can easily fix that. It will cost more at first to install the solar lighting, but the money that will be saved in electric bills will more than make up for it.

You can chose the style, shape, and color of the lighting based upon your personal taste and the style of the rest of your garden. Plastic dome lighting is common, for example. This type is used most often for pathways or borders. There are spikes on the bottom so you can simply stick the lights into the ground.

Other shapes that are available include tubes, discs, lanterns, tiki torches, and globes. Besides putting them in the ground, you can mount some on your home or deck, or hang them on poles, etc. The number of options is amazing.

Light can add a really special quality to your garden, especially if you use the area to entertain friends and family in the evenings.

In addition to working well and looking great, landscape solar garden lights are good for the environment and your electricity bill. The lights are a great investment that will last.

Solar vehicles

Development of a solar powered car has been an engineering goal since the 1980s. The World Solar Challenge is a biannual solar-powered car race, where teams from universities and enterprises compete over 3,021 kilometres (1,877 mi) across central Australia from Darwin to Adelaide. In 1987, when it was founded, the winner's average speed was 67 kilometres per hour (42 mph) and by 2007 the winner's average speed had improved to 90.87 kilometres per hour (56.46 mph).[81] The North American Solar Challenge and the planned South African Solar Challenge are comparable competitions that reflect an international interest in the engineering and development of solar powered vehicles.[82][83]

Some vehicles use solar panels for auxiliary power, such as for air conditioning, to keep the interior cool, thus reducing fuel consumption.[84][85]

In 1975, the first practical solar boat was constructed in England.[86] By 1995, passenger boats incorporating PV panels began appearing and are now used extensively.[87] In 1996, Kenichi Horie made the first solar powered crossing of the Pacific Ocean, and the sun21 catamaran made the first solar powered crossing of the Atlantic Ocean in the winter of 2006–2007.[88] There are plans to circumnavigate the globe in 2010.[89]


Helios UAV in solar powered flight.In 1974, the unmanned AstroFlight Sunrise plane made the first solar flight. On 29 April 1979, the Solar Riser made the first flight in a solar powered, fully controlled, man carrying flying machine, reaching an altitude of 40 feet (12 m). In 1980, the Gossamer Penguin made the first piloted flights powered solely by photovoltaics. This was quickly followed by the Solar Challenger which crossed the English Channel in July 1981. In 1990 Eric Raymond in 21 hops flew from California to North Carolina using solar power.[90] Developments then turned back to unmanned aerial vehicles (UAV) with the Pathfinder (1997) and subsequent designs, culminating in the Helios which set the altitude record for a non-rocket-propelled aircraft at 29,524 metres (96,860 ft) in 2001.[91] The Zephyr, developed by BAE Systems, is the latest in a line of record-breaking solar aircraft, making a 54-hour flight in 2007, and month-long flights are envisioned by 2010.[92]

A solar balloon is a black balloon that is filled with ordinary air. As sunlight shines on the balloon, the air inside is heated and expands causing an upward buoyancy force, much like an artificially heated hot air balloon. Some solar balloons are large enough for human flight, but usage is generally limited to the toy market as the surface-area to payload-weight ratio is relatively high.[93]

Solar sails are a proposed form of spacecraft propulsion using large membrane mirrors to exploit radiation pressure from the Sun. Unlike rockets, solar sails require no fuel. Although the thrust is small compared to rockets, it continues as long as the Sun shines onto the deployed sail and in the vacuum of space significant speeds can eventually be achieved.[94]

The High-altitude airship (HAA) is an unmanned, long-duration, lighter-than-air vehicle using helium gas for lift, and thin-film solar cells for power. The United States Department of Defense Missile Defense Agency has contracted Lockheed Martin to construct it to enhance the Ballistic Missile Defense System (BMDS).[95] Airships have some advantages for solar-powered flight: they do not require power to remain aloft, and an airship's envelope presents a large area to the Sun.

Information about Solar Energy

Information about Solar Energy

Solar energy, radiant light and heat from the Sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar radiation, along with secondary solar-powered resources such as wind and wave power, hydroelectricity and biomass, account for most of the available renewable energy on Earth. Only a minuscule fraction of the available solar energy is used.

Solar powered electrical generation relies on heat engines and photovoltaics. Solar energy's uses are limited only by human ingenuity. A partial list of solar applications includes space heating and cooling through solar architecture, potable water via distillation and disinfection, daylighting, solar hot water, solar cooking, and high temperature process heat for industrial purposes.To harvest the solar energy, the most common way is to use solar panels

Solar technologies are broadly characterized as either passive solar or active solar depending on the way they capture, convert and distribute solar energy. Active solar techniques include the use of photovoltaic panels and solar thermal collectors to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light dispersing properties, and designing spaces that naturally circulate air.

How to Store Solar Energy

Storing solar energy in the form of hydrogen for fuel cells.

The current technology might have enabled us to install a solar plant right on our rooftops, but all that energy is of no use if there isn’t enough storage medium available. Currently most PV plants use batteries as a storage medium, which not only is an expensive way but the low-energy density of batteries makes them impractical for normal use.


Daniel Nocera, a researcher at MIT, is working on the development of a practical, inexpensive storage system that can also offer better energy density than conventionally used batteries. The researcher has proposed a system that mimics photosynthesis in plants and uses solar energy to split water molecules into oxygen and hydrogen. While the oxygen generated during the process is released into the atmosphere, hydrogen is used to power fuel cells.

While the energy density of batteries is about 0.5MJ/kg, the energy density of liquid fuels is about 50MJ/kg. Nocera’s approach of using the solar energy to produce fuel for a fuel cell could be the key to offering affordable personalized solar energy in the not-too-distant future.

Facts About Solar Energy

General facts

Solar Energy is better for the environment than traditional forms of energy.

Solar energy has many uses such as electricity production and heating of water through photovoltaic cells and directly for drying clothes.

Solar energy can also be used to heat swimming pools, power cars, for attic fans, calculators and other small appliances. It produces lighting for indoors or outdoors.

You can even cook food with solar energy.

Solar Energy is becoming more and more popular. The worldwide demand for Solar Energy is currently greater than supply.



Facts about Solar Energy usage:

Solar Energy is measured in kilowatt-hour. 1 kilowatt = 1000 watts.

1 kilowatt-hour (kWh) = the amount of electricity required to burn a 100 watt light bulb for 10 hours.

According to the US Department of Energy, an average American household used approximately 866-kilowatt hours per month in 1999 costing them $70.68.

About 30% of our total energy consumption is used to heat water.



Facts about Solar Energy systems:

A home solar system is typically made up of solar panels, an inverter, a battery, a charge controller, wiring and support structure.

A 1-kilowatt home solar system takes about 1-2 days to install and costs around US$10,000, but can vary greatly and does not take into account any incentives offered by the government.

A 1-kilowatt home solar system consists of about 10-12 solar panels and requires about 100 square feet of installation area.

A 1 kilowatt home solar system will generate approximately 1,600 kilowatt hours per year in a sunny climate (receiving 5.5 hours of sunshine per day) and approximately 750 kilowatt hours per year in a cloudy climate (receiving 2.5 hours of sunshine per day).

A 1-kilowatt home solar system will prevent approximately 170 lbs. of coal from being burned, 300 lbs of CO2 from being released into the atmosphere and 105 gallons of water from being consumed each month!


About 40 solar cells are usually combined into a solar panel and around 10-12 panels mounted in an array facing due North to receive maximum sunlight.

The system usually comes with a 5-year warranty, although the solar panels are warranted for 20.

Relying on the battery back up, a solar energy system can provide electricity 24x7, even on cloudy days and at night.

Solar panels come in various colours.

Solar energy can be collected and stored in batteries, reflected, insulated, absorbed and transmitted.



Other Interesting Facts about Solar Energy:

Da Vinci predicted a solar industrialization as far back as 1447.

In one hour more sunlight falls on the earth than what is used by the entire population in one year.

A world record was set in 1990 when a solar powered aircraft flew 4060km across the USA, using no fuel.

Fierce weather cost the world a record $130 Billion in the first eleven months of 1998- more money than was lost from weather related disasters from 1980 to 1990 ($82 Billion).

Researchers from the Worldwatch Institute and Munich Re blame deforestation and climate change from Earth warming for much of the loss. The previous one-year record was $90 Billion in 1996. Source - Associated Press, November 28,1998.

About 2 billion people in the world are currently without electricity.

Accounting for only 5 percent of the world's population, Americans consume 26 percent of the world's energy.

Electric ovens consume the most amount of electricity, followed by microwaves and central air conditioning.

Third world countries with an abundance of sunlight and a population currently without electricity, represents the fastest growing market for solar energy, with the largest domestic market being the utilities sector.

Shell Oil predicts that 50% of the world's energy will come from renewable sources by 2040.

What Is Solar Energy?

Solar energy is power from the sun's rays that reaches the earth. Using photovoltaic cells made from silicon alloys, sunlight can be converted into other forms of energy, such as heat and electricity. Steam generators using thermal collectors to heat a fluid, such as water, sometimes convert even higher amounts of solar energy into electricity.

What Are the Benefits?

Volatile energy prices have fueled interest in alternatives such as solar energy. Using solar power can help alleviate capacity problems on local utility systems, especially during peak electricity demand periods. It also reduces greenhouse gas emissions by lowering the use of electricity generated by fossil-fuel power plants.

Basics of Solar Energy

The history of solar energy materials began in the 1970s with the first silicon-based photovoltaic (PV) cells. These basic cells were created by doping silicon to form two oppositely charged layers. A positively charged or p-type layer underneath a negatively charged or n-type layer. In first configurations the p-type layer was doped with Boron to create the positive charge and n-type layer was doped with phosphorous.

When the sun's energy in the form of photons collects in the cell layers in a volume sufficient to force electrons in the layer materials from their "Valence Band" to their "Conduction Band", electrons from the layers are released. This energy threshold is referred to as the "Band Gap". These freed electrons naturally attempt to flow from the negatively charge N-type layer to the positively charged P-type layer. For this reason, the P-type layer is also sometimes called the "Absorption Layer" and the N-Type layer is called the "Emitter Layer".

However, the boundary between these two layers, which is called the "P-N Junction" or "Adhesion Layer" blocks their flow. Collection circuits are attached from the N-type layer to the P-type layer to allow for the electrons to reach their target and complete the circuit. Energy in the form of electricity is collected or harvested from this external circuit.

These silicon based photovoltaic cells have gone through several generations of development designed to reduce production costs. Originally the layers were produced by growing and slicing doped single crystals of silicon. To save cost producers began casting shapes using polycrystalline silicon. While less expensive to produce, efficiencies are also lower. A silicon single crystal may have as high as 30% efficiency; polycrystalline silicon might reach 10-15%. The least expensive approach but also the least efficient cell (approximately 5%) is produced through thin film deposition of amorphous silicon using sputtering techniques.

Presently, most silicon-based PV solar cells are produced from polycrystalline silicon with single crystal systems the next most common.

All silicon-based photovoltaic solar energy collectors however suffer from their ability to absorb energy from a relatively narrow range of the sun's light wave emission. Substantial research ha gone into developing materials that can either expand the band gap or create multiple band gaps in order to absorb a greater portion of the solar energy spectrum. This has lead to the development of PV cells based on Copper Indium Selenide (CuInSe2) or "CIS" Absorption Layers which can capture energy from portions of the light's spectrum not collected by silicon-based PV cells. Doping CIS with Gallium increases the band gap even further and as such most PV cells are now based on Copper Indium Gallium Selenide (CuInGaSe2) and are referred to as "CIGS".

In the typical CIGS photovoltaic cell, the CIGS layer acts as the the P-type or absorption layer. A second material, Cadmium Selenide (CdSe) functions as the emitter or N-type layer. Because two different materials are uses these are sometimes referred to as "Heterojunction" systems. The external circuit is provided by a zinc oxide contact layer on the N-Type layer and a Molybdenum metal contact layer on the P-Type layer.

CIGS based solar cells are a rapidly growing segment of the solar energy market. Besides being more efficient that silicon-based solar cells and therefore less expensive per watt of energy generated, they can be designed to bend to complex geometries and are very light weight. Due to their high efficiency, layers can be achieved using thin film techniques. Thin film deposition of Silicon Nanoparticle quantum dots on the polycrystalline silicon substrate of a photovoltaic (solar) cell increases voltage output as much as 60% by fluorescing the incoming light prior to capture.

Other promising designs include cells based on III-IV Nitride materials and research on Zinc Manganese Telluride, Cadmium Telluride (CdTe) and Gallium Selenide P-Type layers.

The band gap for III-IV Nitride materials, such as Gallium Indium Nitride, covers nearly the entire energy spectrum of the sun because of multiple band gaps in the semiconductor materials. Similarly, Zinc Manganese Telluride crystals have three band gaps which can absorb greater than 50% of the solar energy spectrum.

Building a Solar Oven

Our sun is a constant source of energy. Each day, the sun bathes the Earth in unimaginable amounts of solar energy, most of which comes in the form of visible light. All over planet Earth, sunlight is by far the most important source of energy for all living things. Without it, Earth would be lifeless.



Sunlight can be a practical source of energy for such everyday jobs as cooking, heating water, or warming up homes. The challenge is to find ways to transform sunlight into usable heat. The most efficient way to transform sunlight into heat is to shine lots of sunlight onto a dark surface. Dark surfaces absorb most of the visible light that falls upon them, and reflect very little. Visible light that is absorbed this way usually causes the dark-colored surface to warm up. Of all colors, black is able to absorb the most light, and produce the most heat.

Safety Precautions


Use extreme caution when cutting cardboard with the utility knife. Extend the blade only as far as is needed to cut through the cardboard, and lock it into place. Do your cutting on a cutting board or piece of scrap plywood, cardboard, or a kitchen cutting board.
Use sunglasses when working with shiny materials in sunlight.
Solar ovens can get very hot! Use oven mitts or gloves to prevent burns

What Is Solar Energy?

Solar energy is radiant energy that is produced by the sun. Every
day the sun radiates, or sends out, an enormous amount of energy.
The sun radiates more energy in one second than people have
used since the beginning of time!
Where does the energy come from that constantly radiates from
the sun? It comes from within the sun itself. Like other stars, the
sun is a big ball of gasesññmostly hydrogen and helium atoms.
The hydrogen atoms in the sunís core combine to form helium
and generate energy in a process called nuclear fusion.
During nuclear fusion, the sunís extremely high pressure and
temperature cause hydrogen atoms to come apart and their nuclei
(the central cores of the atoms) to fuse or combine. Four hydrogen
nuclei fuse to become one helium atom. But the helium atom
contains less mass than the four hydrogen atoms that fused.
Some matter is lost during nuclear fusion. The lost matter is
emitted into space as radiant energy.
It takes millions of years for the energy in the sunís core to make
its way to the solar surface, and then just a little over eight
minutes to travel the 93 million miles to earth. The solar energy
travels to the earth at a speed of 186,000 miles per second, the
speed of light.
Only a small portion of the energy radiated by the sun into space
strikes the earth, one part in two billion. Yet this amount of energy
is enormous. Every day enough energy strikes the United States
to supply the nationís energy needs for one and a half years!
Where does all this energy go? About 15 percent of the sunís
energy that hits the earth is reflected back into space. Another
30 percent is used to evaporate water, which, lifted into the
atmosphere, produces rainfall. Solar energy also is absorbed by
plants, the land, and the oceans. The rest could be used to supply
our energy needs.


History of Solar Energy

People have harnessed solar energy for centuries. As early as
the 7th century B.C., people used simple magnifying glasses to
concentrate the light of the sun into beams so hot they would
cause wood to catch fire.
More than 100 years ago in France, a scientist used heat from a
solar collector to make steam to drive a steam engine. In the
beginning of this century, scientists and engineers began
researching ways to use solar energy in earnest. One important
development was a remarkably efficient solar boiler invented by
Charles Greeley Abbott, an American astrophysicist, in 1936.
The solar water heater gained popularity at this time in Florida,
California, and the Southwest. The industry started in the early
1920s and was in full swing just before World War II. This growth
lasted until the mid-1950s when low-cost natural gas became the
primary fuel for heating American homes.
The public and world governments remained largely indifferent
to the possibilities of solar energy until the oil shortages of the
1970s. Today, people use solar energy to heat buildings and
water and to generate electricity.
Solar Collectors
Heating with solar energy is not as easy as you might think.
Capturing sunlight and putting it to work is difficult because the
solar energy that reaches the earth is spread out over such a
large area.
sources for the future.

How to make Solar Energy economical

Installation of solar panel is costly but it acts as a long-term solution for power scarcity, electricity bills and they are environment friendly too.

Solar panel can also be made at home with the help of readymade solar panel kits with their instruction manual or you can also purchase it from some solar panel producer
In a typical manner, these panels are installed on the roof or building tops in order to get as much exposure to the direct rays of sun as possible. Solar panels can also be installed with the help of Solar panel mounts.

Solar panels are broadly of two types namely flat plate collector and evacuated tubes. Flat Plate Collectors consist of a sheet of metal (copper or stainless steel) coated with some heat absorbing material. At the back side of this plate are some copper pipes. An insulated box contains both pipes and metal plate. As water circulates through pipes heat is transferred from plate to pipe which works as hot water cylinder. Evacuated tubes consist of an evacuated glass tube in addition which makes sure that very less energy gets lost from the metal sheet.

The solar panels which convert solar energy into electricity are called Photovoltaic. The basic component of a solar panel is silicon cell which is made up of semiconductors and when large amount of silicon cells are assembled together, they generate significant amount of energy.

For best maintenance and efficient usage of your solar panel you should remove all the useless items which make obstruction in the path of sunlight. Trim the branches if some tree is creating obstruction. If you find any shadow over your solar panel, you are definitely affecting the efficient utilization of your solar plant.

Solar Panel Information

What shapes, sizes and types do solar panels come in?
Solar panels (a.k.a. Photovoltaic or PV modules) vary in length and width, and are often about 2 inches thick. They are generally about 30 pounds or less, but the larger ones (5' x 3') can be cumbersome to carry on the roof. We carry a wide selection of solar panels: framed, foldable, rollable and laminates for the roof. Framed solar panels are the industry standard, most cost effective, and applicable for most home solar panels applications.
Foldable Solar Panels are lightweight (less than 5 pounds) and can fold up and fit easily in a backpack. Flexible / Rollable Solar Panels are also lightweight, but bulkier than the foldable panels. Many people use these rollable panels on boats because they are durable and can be easily stowed after use. Roofing Solar Panels (laminates) are becoming more common, but are still available on a limited basis for now. Generally these thin-film laminates are more expensive per watt and require more square footage to produce the same wattage of equally sized framed module.
What size solar panels do I need and how many?
The number of solar panels you will need depends primarily upon the amount of electricity you are trying to produce and the insolation in your area. Insolation can be thought of as the number of hours in the day that the solar panel will produce its rated output. This is not equivalent to the number of daylight hours. You'll find solar panels in a variety of wattages. Watts are the main measure of a solar panel, along with nominal voltage . For a rough idea of how many watts of solar you will need, start by dividing your electrical usage (in watt-hours per day) by the insolation in your area. Bump that number up by 30-50% (to cover system inefficiencies) and you'll have an idea of the number of watts of solar panels you will need. If that number is more than 1000 watts, you are talking about $10K or more for the solar electric system. (Could we take this opportunity to mention the importance of energy efficiency again?!) If you could still use a little help with the math, please give us a call and tell us how much electricity you are trying to produce (in kwh/month or watt-hours/ day ) and your location, and we'll help get you started.
What types of solar panels are there?
Most solar panels can be classified as monocrystalline, polycrystalline or amorphous. This is based on the silicon structure that comprises the cell. It's not quite as complicated as it sounds. Basically a 100 watt monocrystalline solar panel should have the same output as a 100 watt polycrystalline panel and a 100 watt amorphous panel. The main difference is the amount of space which the panel occupies. Because the monocrystalline structure is more efficient than amorphous in turning sunlight into electricity, the amorphous panel of the same wattage will be physically larger. By the way, when talking about efficiency of solar panels, keep in mind that solar panel efficiency is still only about 13-18% efficient in turning sunlight into electricity. Often amorphous panels are less expensive than the crystalline panels. If space is not an issue, than an amorphous panel could be a great option. Additionally, amorphous panels perform better than crystalline panels in very hot temperatures and are also slightly more tolerant of partial shading.

Solar Energy Definition

The energy transmitted from the Sun. The upper atmosphere of Earth receives about 1.5 × 1021 watt-hours (thermal) of solar radiation annually. This vast amount of energy is more than 23,000 times that used by the human population of this planet, but it is only about one two-billionth of the Sun's massive outpouring—about 3.9 × 1020 MW.

The power density of solar radiation measured just outside Earth's atmosphere and over the entire solar spectrum is called the solar constant. According to the World Meteorological Organization, the most reliable (1981) value for the solar constant is 1370 ± 6 W/m2.

Solar radiation is attenuated before reaching Earth's surface by an atmosphere that removes or alters part of the incident energy by reflection, scattering, and absorption. In particular, nearly all ultraviolet radiation and certain wavelengths in the infrared region are removed. However, the solar radiation striking Earth's surface each year is still more than 10,000 times the world's energy use. Radiation scattered by striking gas molecules, water vapor, or dust particles is known as diffuse radiation. Clouds are a particularly important scattering and reflecting agent, capable of reducing direct radiation by as much as 80 to 90%. The radiation arriving at the ground directly from the Sun is called direct or beam radiation. Global radiation is all solar radiation incident on the surface, including direct and diffuse.

Solar research and technology development aim at finding the most efficient ways of capturing low-density solar energy and developing systems to convert captured energy to useful purposes. Also of significant potential as power sources are the indirect forms of solar energy: wind, biomass, hydropower, and the tropical ocean surfaces. With the exception of hydropower, these energy resources remain largely untapped.

Five major technologies using solar energy are being developed. (1) The heat content of solar radiation is used to provide moderate-temperature heat for space comfort conditioning of buildings, moderate- and high-temperature heat for industrial processes, and high-temperature heat for generating electricity. (2) Photovoltaics convert solar energy directly into electricity. (3) Biomass technologies exploit the chemical energy produced through photosynthesis (a reaction energized by solar radiation) to produce energy-rich fuels and chemicals and to provide direct heat for many uses. (4) Wind energy systems generate mechanical energy, primarily for conversion to electric power. (5) Finally, a number of ocean energy applications are being pursued; the most advanced is ocean thermal energy conversion, which uses temperature differences between warm ocean surface water and cooler deep water to produce electricity.

Solar energy can be converted to useful work or heat by using a collector to absorb solar radiation, allowing much of the Sun's radiant energy to be converted to heat. This heat can be used directly in residential, industrial, and agricultural operations; converted to mechanical or electrical power; or applied in chemical reactions for production of fuels and chemicals.

A solar energy system is normally designed to be able to deliver useful heat for 6 to 10 h a day, depending on the season and weather. Storage capacity in the solar thermal system is one way to increase a plant's operating capacity.

There are four primary ways to store solar thermal energy: (1) sensible-heat-storage systems, which store thermal energy in materials with good heat-retention qualities; (2) latent-heat-storage systems, which store solar thermal energy in the latent heat of fusion or vaporization of certain materials undergoing a change of phase; (3) chemical energy storage, which uses reversible reactions (for example, the dissociation-association reaction of sulfuric acid and water); and (4) electrical or mechanical storage, particularly through the use of storage batteries (electrical) or compressed air (mechanical).

Photovoltaic systems convert light energy directly to electrical energy. Using one of the most versatile solar technologies, photovoltaic systems can, because of their modularity, be designed for power needs ranging from milliwatts to megawatts. They can be used to provide power for applications as small as a wristwatch to as large as an entire community. They can be used in centralized systems, such as a generator in a power plant, or in dispersed applications, such as in remote areas not readily accessible to utility grid lines.

Biomass energy is solar energy stored in plant and animal matter. Through photosynthesis in plants, energy from the Sun transforms simple elements from air, water, and soil into complex carbohydrates. These carbohydrates can be used directly as fuel (for example, burning wood) or processed into liquids and gases (for example, ethanol or methane). Biomass is a renewable energy resource because it can be harvested periodically and converted to fuel.

Wind is a source of energy derived primarily from unequal heating of Earth's surface by the Sun. Energy from the wind has been used for centuries to propel ships, to grind grain, and to lift water. Wind turbines extract energy from the wind to perform mechanical work or to generate electricity.

Ocean thermal energy conversion uses the temperature difference between surface water heated by the Sun and deep cold water pumped from depths of 2000 to 3000 ft (600 to 900 m). This temperature difference makes it possible to produce electricity from the heat engine concept. Since the ocean acts as an enormous solar energy storage facility with little fluctuation of temperature over time, ocean thermal energy conversion, unlike most other renewable energy technologies, can provide electricity 24 h a day.

Home Build Solar System

I could see that my electricity bill was increasing year after year, mostly because my modern day appliances can’t be turned off anymore. I noticed that I had many appliances in the house which are on standby day in and day out. This not only harms the environment, but also my bank account as I am using electricity for nothing. Unable to solve this problem (as this is how appliances are designed and I can’t change this), I started to look into renewable energy to compensate for my unneeded losses and to take some pain from my bank account.


Wind energy is not an option in the area I’m living in and hydroelectricity is not an option as I live in a flat country with almost no rivers, so solar power is the best solution. Then the price of solar systems appears to be horrendous: far more than the system would ever pay for itself in its estimated 20 year lifespan. So I tried to get governmental grants for this project, but grants for those kinds of systems were limited and I missed out. I still wanted a solar system, but I didn’t wanted to pay the high price, so I decided to build the panels myself. Yes, you are reading this correctly, I wanted to build my own solar panel system and I can tell you now that it is possible with materials and parts bought locally in DIY shops and from the Internet. No, I’m not a technical wonder and I don’t have lots of experience working with electricity. I just looked around and taught myself how solar panels are made, how other might have done it, and made out of this a workable plan of how I could do it.

Solar energy can help mitigate global warming

Solar energy has the power to reduce greenhouse gases and provide increased energy efficiency, says a scientist at the U.S. Department of Energy's Argonne National Laboratory, in a report (view it online) published in the March issue of Physics Today.

Last month, the Intergovernmental Panel on Climate Change (IPCC) of the United Nations released a report confirming global warming is upon us and attributing the growing threat to the man-made burning of fossil fuels.

Opportunities to increase solar energy conversion as an alternative to fossil fuels are addressed in the Physics Today article, co-authored by George Crabtree, senior scientist and director of Argonne's Materials Science Division, and Nathan Lewis, professor of Chemistry at Caltech and director of its Molecular Materials Research Center.

Currently, between 80 percent and 85 percent of our energy comes from fossil fuels. However, fossil fuel resources are of finite extent and are distributed unevenly beneath Earth's surface. When fossil fuel is turned into useful energy through combustion, it often produces environmental pollutants that are harmful to human health and greenhouse gases that threaten the global climate. In contrast, solar resources are widely available and have a benign effect on the environment and climate, making it an appealing alternative energy source.

“Sunlight is not only the most plentiful energy resource on earth, it is also one of the most versatile, converting readily to electricity, fuel and heat,” said Crabtree. “The challenge is to raise its conversion efficiency by factors of five or ten. That requires understanding the fundamental conversion phenomena at the nanoscale. We are just scratching the surface of this rich research field.”

Argonne carries out forefront basic research on all three solar conversion routes. The laboratory is creating next-generation nanostructured solar cells using sophisticated atomic layer deposition techniques that replace expensive silicon with inexpensive titanium dioxide and chemical dyes. Its artificial photosynthesis program imitates nature using simple chemical components to convert sunlight, water and carbon dioxide directly into fuels like hydrogen, methane and ethanol. Its program on thermoelectric materials takes heat from the sun and converts it directly to electricity.

The Physics Today article is based on the conclusions contained in the report of the Basic Energy Sciences Workshop on Solar Energy Utilization sponsored by the U.S. Department of Energy. Crabtree and Lewis served as co-chairs of the workshop and principal editors of the report. The key conclusions of the report identified opportunities for higher solar energy efficiencies in the areas of:

Electricity – important research developments lie in the development of new, less expensive materials for solar cells, including organics, thin films, dyes and shuttle ions, and in understanding the dynamics of charge transfer across nanostructured interfaces.

Fuel – solar photons can be converted into chemical fuel more resourcefully by breeding or genetically engineering designer plants, connecting natural photosynthetic pathways in novel configurations and using artificial bio-inspired nanoscale systems.
Heat – controlling the size, density and distribution of nanodot inclusions during bulk synthesis could enhance thermoelectric performance and achieve more reliable and inexpensive electricity production from the sun's heat.

The nation's first national laboratory, Argonne National Laboratory conducts basic and applied scientific research across a wide spectrum of disciplines, ranging from high-energy physics to climatology and biotechnology. Since 1990, Argonne has worked with more than 600 companies and numerous federal agencies and other organizations to help advance America's scientific leadership and prepare the nation for the future. Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

Developments in Solar Power Towers

On August 5th, the company eSolar opened the Sierra Sun Tower, the newest example solar power towers. According to the website of esolar, the Sierra facility supplies 5 MW of clean, renewable energy to the grid. As the only commercial CSP tower in the United States, supplies electricity to Southern California Edison (SCE) and will power up to 4,000 homes. Many bloggers and journalists welcome it as a promising development.

UBS Wealth Management, moreover, is predicting that the relatively small market for concentrated solar power tends to expand, with projected growth of almost 20 gigawatts in new capacity over the next decade. UBS analysts Gianrento Gamboni and Christoph Hugi, refers to the new projects in the United States and Spain as they say “After a long period of stagnation, the market is evolving more dynamically.”
• What is a solar power tower?
One square kilometer of land holds the capacity – depending on the specifities of location – to generate as much as 100 gigawatt hours (GWh) of electricity per year through solar thermal technology. To make it clear, this amount is enough to run 50,000 residences.
One option to produce this energy is the solar power tower, which is a type of solar thermal plant that uses a tower to receive the sunlight, focused upon it via an array of flat, movable mirrors (ie. heliostats). These focused rays heats the water and the steam produced powers a turbine. As you see, no pollutants are emitted in producing the electricity.
Today liquid sodium is commonly used instead of water to store the energy during brief interruptions in sunlight or in night time.
• A major advantage: Solar thermal plants produce electricity whose current and future costs are known.
It is a fixed-cost generation resource know to the consumer in advance and it decreases consumers’ exposure to market fluctuations and the volatile cost of natural gas (which solar thermal typically replaces in the portfolio).
• A major disadvantage: Solar thermal power plants are huge
It uses a huge land desirably less than 3 percent slope. With respect to the electricity output versus total size, they make use of the land more effectively than coal plants or hydroelectric dams, though.
The best locations for solar power plants are massive lands, such as deserts, for which there might be few other uses; but again, then comes the problem of how to provide the necessary water.
The factsheet in the released in the webpage of governement of CA, claims that as experience is gained with this technology, the acreage requirements
will likely be reduced due to more efficient placement of the heliostats.
• Five Earlier Examples:
1. Solar One, a pilot solar-thermal project built in the Mojave Desert (CA, USA) was the first test of a large-scale thermal solar power tower plant. It was designed by the Department of Energy (DOE), Southern California Edison, LA Dept of Water and Power, and California Energy Commission. Solar One’s method of collecting energy was based on producing heat to drive a steam turbine.
2. Later, in 1995 it was converted into Solar Two, with the addition of a second ring of 108 larger heliostats around the existing Solar One. The total number of heliostats became 1926 on an area of 82,750 m². Solar Two used molten salt, which is a combination of 60% sodium nitrate and 40% potassium nitrate, instead of water.
3. Solar Tres, which is located in the city of Écija, in Andalusia, Spain and received a subsidy of five million Euro from the European Commission, follows the Solar Two in using molten salt but is designed to be three times of it in size.
4. Europe’s first commercial solar tower PS10 is located near the Southern Spanish city of Seville. It produces electricity of 11 MW with 624 large heliostats with surfaces of 120 square meters each. The height the tower is 115 meters.
5. The PS20 solar power tower is also near Seville. The capacity is 20 megawatt. The tower is taller than PS10, it is 160 meters.
6. The THEMIS solar power tower, located near the village of Targassonne, in the département of Pyrénées-Orientales, South of France, is a R&D center focused on solar energy, as well as a photovoltaic power facility and a solar thermal energy plant. It had a power output of 2 MW in 1983.

How Solar Cells Work

­You've probably seen calculators that have solar cells -- calculators that never need batteries, and in some cases don't even have an off button. As long as you have enough light, they seem to work forever. You may have seen larger solar panels -- on emergency road signs or call boxes, on buoys, even in parking lots to power lights.


Although these larger panels aren't as common as solar powered calculators, they're out there, and not that hard to spot if you know where to look. There are solar cell arrays on satellites, where they are used to power the electrical systems.

­­
Yo­u have probably also been hearing about the "solar revolution" for the last 20 years -- the idea that one day we will all use free electricity fro­m the sun. This is a seductive promise: On a bright, sunny day, the sun shines approximately 1,000 watts of energy per square meter of the planet's surface, and if we could collect all of that energy we could easily power our homes and offices for free.

­In this article­, we will examine solar cells to learn how they convert the sun's energy directly into electricity. In the process, you will learn why we are getting closer to using the sun's energy on a daily basis, and why we still have more research to ­do before the process becomes cost effective.

A Solar Battery Charger You Probably Already Have At Home

When a friend of mine ran one of my garden solar lights, this was broken in several pieces, but the small solar panel and battery compartment remained intact. I looked closely at the value of the small engine. The battery compartment houses two AA NiCd (which come with the unit) and connects with a cable directly to small solar panels. A simple engineering of solar energy. I have no garden light that works, but I have a AA battery solar charger, which is not bad for only $ 5USD. Only two AA rechargeable batteries are sold in Radio Shack for $ 10.

When I see that I have a pair of NiCd batteries that need energy only left out in the sun for several hours in my new garden solar charger.

If you have no sunlight to garden, I’m sure you have seen them sold in packs of 4 pieces up to $ 20 USD. No need to break one. They can be kept intact so that they can use for their original purpose or as a battery charger.

It’s a great article that can be carried to the camps and trips as a charger for appliances and a solar light.

The production of energy from residues is an evident reality, or at least this is one of the conclusions of more than 400 delegates from 20 countries that happened these days in Madrid on the occasion of the II International Conference on Obtaining of Energy from Residues and Biomass. Every time the number of new formulas to get advantage of the energy increases; coming from food leftovers, plastics, and other material. Thus, residues and biomass can contribute of remarkable way to the production of clean energies: as much, that within ten years the residues could contribute 8% of all the energy that is consumed in Spain, according to they concluded the assistants to this Conference of three days organized by the Institute for the Sustainability of Resources (ISR), and that closed on Friday.

During the sessions and debates the experts showed that the potential power of the residues and the biomass “is especially important because it contributes of decisive way to diminish the environmental impact of the garbage dumps, one of the great problems of the present society”. In words of the general assistant director of Prevention of Residues of the Ministry of Environment, Juan Martinez Sanchez, “every time we generated more residues and more complex, and if we are not able to establish effective measures for its reduction, really dreadful scenes consider”. At the moment, in Spain, 24 million tons of annual urban residues are generated –540 kilos by inhabitant and year–, from that a 60% arrive at the garbage dumps. “Most of these sweepings could take advantage to do of a useful raw material like the recycled ones and re-use the remainder, or like the gasohol, the synthetic gas, biogas, the heat or electricity”, Martinez explained.

In fact, according to data of the ISR, with the new technologies and the already existing ones, “the sweepings of the garbage dumps could be reduced in a drastic form until a 10%”, but for it “it is necessary to continue investigating in biological, chemical and thermal processes that allow to advance towards a low society in carbon and with spill zero”, added on the other hand the chief of a main directorate of the ISR, Carlos Martinez Orgado. One of the new techniques to transform the residues into energy is one that is being experienced successfully in Ottawa (Canada). The plant uses one hundred tons of residues per the day –industrial and chemical plastics, electric home appliances or remainders– that after a process of gasification by plasma it obtains a synthetic gas of high calorific power similar to the natural gas. In Spain, a company of the sector already expects the necessary permissions to begin the construction of the first plant of this type in our country; it will be located in Carrión de los Condes (Palencia). Another alternative technique is the chemical plastic recycling, that before only could be eliminated by means of the incineration. The idea is to invest the process of manufacture of some rich carbon products, like the plastic, to obtain that the remainder returns to become raw material again, closing therefore the cycle of the materials: resource-product-remainder-resource. This method, in experimentation at the moment, consists on disturbing the polymer molecule to produce fuel-oil.

HYDROGEN IS THE ENERGY OF THE FUTURE.

During the course of this international conference the potential of the residues to produce hydrogen was discussed, the main power plant of the future. Through processes of photosynthesis, or by means of the use of bacteria, it is possible to obtain hydrogen in a continued way from renewable raw materials and residues. “With these techniques we will not be able to cover the energetic demand of the future, but it can be very useful for the micro energy: small plants distributed by all the national territory to give service in rural populations”, explained the university professor of the Department of Geo-engineering and Environmental Technologies of the University of Cagliari (Italy), Aldo Muntoni. The conference showed the great diversity of sources and methods to obtain energy from residues and biomass, as the emergent technologies happening through biological treatments, chemical processes, etc.

Solar Panels

Using solar panels is a great way to generate clean and renewable electricity to power remote appliances, or even the average home.

There are two main forms of solar cells in existence today, and these are; "solar electricity panels" and "solar hot water panels". The two different technologies allow us to either generate electricity for our homes or to heat the water we use.

As time goes by, we begin to see new and more efficient solar panel designs. This is making the use of photovoltaic power over fossil fuels, much more viable to homeowners and businesses.

It is unlikely we will see heavy industry using photovoltaic electricity for quite some time due to the much larger energy demand industry requires, but who knows where photovoltaic electricity will take us in future years.

As the technologies surrounding the use of photovoltaics improve, we are likely to see a much greater, widespread use of solar cells.

Solar electricity generating capacity has on average doubled every two years since 1998

Solar power generating capacity grew 69% in 2008, the fastest rate of growth in our database which goes back to 1996. Total capacity grew by 5.5 GW to reach 13.4 GW. Growth averaged 42% pa over the past 10 years – at that rate solar capacity doubles every two years.
Growth in 2008 was highly concentrated – Spain (2.7 GW) and Germany (1.5 GW) together accounted for more than 75% of the growth, due to continued strong government support for solar power in those markets.

The concept of Spray on Solar Power Cells

Solar energy is one of the many renewable sources of energy that is today used for providing electricity and for use in many consumer products. Though solar energy does not emit harmful gases into the atmosphere; it has a drawback that it works only in the presence of sunlight.

So in a bid to overcome this default of solar energy, scientists have now invented a plastic solar cell that has the ability of turning sun power into electricity even on cloudy days.

These plastic solar cells work based on nanotechnology and is the first solar cell that can harness the energy found in the sun’s invisible and infrared rays.
With this finding, theorists predict that plastic solar cells are basically five more times efficient than the technology that is presently used for solar energy.

Making these plastic solar cells is easy as the composite just has to be sprayed onto the material to make it be able to use solar energy. In other words, with this composite, you have a sort of portable source of electricity.
With a sweater that is coated with this composite, you will be able to power a cell phone or any other wireless device.

Make solar energy economical

Why is solar energy important?

Already, the sun’s contribution to human energy needs is substantial — worldwide, solar electricity generation is a growing, multibillion dollar industry. But solar’s share of the total energy market remains rather small, well below 1 percent of total energy consumption, compared with roughly 85 percent from oil, natural gas, and coal.
Those fossil fuels cannot remain the dominant sources of energy forever. Whatever the precise timetable for their depletion, oil and gas supplies will not keep up with growing energy demands. Coal is available in abundance, but its use exacerbates air and water pollution problems, and coal contributes even more substantially than the other fossil fuels to the buildup of carbon dioxide in the atmosphere.
For a long-term, sustainable energy source, solar power offers an attractive alternative. Its availability far exceeds any conceivable future energy demands. It is environmentally clean, and its energy is transmitted from the sun to the Earth free of charge. But exploiting the sun’s power is not without challenges. Overcoming the barriers to widespread solar power generation will require engineering innovations in several arenas — for capturing the sun’s energy, converting it to useful forms, and storing it for use when the sun itself is obscured.
Many of the technologies to address these issues are already in hand. Dishes can concentrate the sun’s rays to heat fluids that drive engines and produce power, a possible approach to solar electricity generation. Another popular avenue is direct production of electric current from captured sunlight, which has long been possible with solar photovoltaic cells.

How do you make solar energy more economical?

Other new materials for solar cells may help reduce fabrication costs. “This area is where breakthroughs in the science and technology of solar cell materials can give the greatest impact on the cost and widespread implementation of solar electricity,” Caltech chemist Nathan Lewis writes in Science. [Lewis 799]
A key issue is material purity. Current solar cell designs require high-purity, and therefore expensive, materials, because impurities block the flow of electric charge. That problem would be diminished if charges had to travel only a short distance, through a thin layer of material. But thin layers would not absorb as much sunlight to begin with.
One way around that dilemma would be to use materials thick in one dimension, for absorbing sunlight, and thin in another direction, through which charges could travel. One such strategy envisions cells made with tiny cylinders, or nanorods. Light could be absorbed down the length of the rods, while charges could travel across the rods’ narrow width. Another approach involves a combination of dye molecules to absorb sunlight with titanium dioxide molecules to collect electric charges. But large improvements in efficiency will be needed to make such systems competitive.

Residential Applications For Solar Energy

Photovoltaic Systems “PV” or solar electric: Compared to solar hot water, photovoltaic (pronounced: foh-toh-vol-tay-ik) is a relatively new technology. The first photovoltaic effect was discovered by Edmund Becquerel, a 19-year old French experimental physicist in 1839. Albert Einstein received a Nobel Prize in 1923 for explaining the photovoltaic effect. But not until Bell Labs in 1954 did solar PV finally reach a level where its power began to be useful for commercial purposes, such as Western Electric’s dollar bill changer in 1955.
Unlike a solar hot water system, which is essentially a plumbing device, PV uses semi-conductors and sunlight to make electricity. The more solar modules a PV system or array has, the more electricity will be generated. DC electricity can be “inverted” into alternating current (AC), so it can be useable power for a home or business, which can off-set or even eliminate the electric bill.
PV systems to power buildings fall into four general categories:
Grid-Interconnected or “Grid-Tied” PV systems are the most popular and use special inverters to allow electricity to flow safely back into the electric grid. When solar power is generated, this power is typically first used by the building, and then surplus electricity can actually flow back into the grid, giving full retail credit per kilowatt-hour from your utility provider. Since there are no batteries, these systems cannot stored energy and are designed to shut down if the grid is down for safety reasons (mainly to protect utility line workers).
Grid-Interconnected with Battery Back-up systems offer customers continued power when the grid goes down, while still being connected to the grid for seamless power. Newer systems also accept other power sources, in addition to PV, such as wind or even traditional gas-powered generators to provide power and/or charge the battery at night and/or if the grid is not available.
“Off-Grid” PV systems are used when a completely independent or “stand alone” system is needed. Since no grid power is used, the system must be carefully designed based on power usage, peak demand and seasonal solar variations. Batteries are typically used to provide power at night, in low sun or high electric demand conditions. These systems are ideal for remote locations where no utilities exist.
Utility-Scale PV systems, sometimes called “solar farms” provide power for regional users by (or in cooperation) with electric utility providers.
Grid-tied systems may be metered by two different methods:
Net metering is the practice of using a single utility meter that “nets out” both what is “drawn” from the grid and what is “returned” or fed back to the grid. When a PV system generates power beyond what the building is consuming, this surplus power is fed back into the utility grid, making the electric meter actually spin backwards. If you generate more electricity than you consume at the end of the month, the customer will receive full retail credit (and possibly cash) from the utility provider per their policy.
Dual metering configurations use two separate meters. One meter tracks the total energy consumed by the building and the other meter tracks total energy produced by the solar and fed back into the grid. Because this method accurately meters both the total energy consumed and solar energy produced, different billing rates can be applied by the utility. This metering method is used for Feed-In-Tariff (FIT) programs where customers can be paid for solar power generated, typically at a higher rate than the conventional electricity purchased.
Regardless of PV system or metering, most homeowners will install a solar hot water system along with the PV system. Why both? Because a solar hot water system is significantly more cost-effective and requires a fraction of the roof space to create the equivalent amount of energy to heat water. This will also allow the PV system to satisfy a higher proportion of household electric demand, making the PV system even more cost-effective.
PV systems are rated by “standard test conditions” (STC) wattage during peak sun intensity. Most residential grid-tied PV systems will typically range from 2 kilowatts to 8 kilowatts. The total energy per year it generates will vary depending on the part of the country in which it is located and other factors related to design and installation. In Florida, for example, a 5 kilowatt PV system will generate about 700 kilowatt-hours per month of clean, renewable energy on average, based on a one-year period. At 15 cents per kilowatt-hour, this will offset $1,260.00 of electricity. As for carbon dioxide, the EPA reports that each kilowatt-hour of electricity produced from a coal creates 2.3 lbs. of carbon dioxide, so this 5 kilowatt residential PV system in Florida will also offset about 19,320 lbs. (9.7 tons) of carbon dioxide per year.

Spain Energy

Spain


A cemetary in Spain recently installed solar panels above its tall columns of deceased “tenants”. The city of Santa Coloma de Gramanet’s plans were initially met with apprehension (shockingly) when officials announced they would be placing 462 solar panels on top of the cemetary’s mausoleums.
So why would this cemetary be selected as a location for the solar panels?
Well, the city (outside of Barcelona) apparently has a population density of over 82,000 people per square mile and is only 1.5 square miles in area. Thus, the cemetary was one of the only open and sunny spots in the whole city.
The good news is that this installation will keep 62 tonnes of carbon dioxide out of the air each year.
The panels cover less than 5% of the cemetary’s surface area and the town government does have plans to install more.

contemplates installing batteries in a standard sized transformer box and assumes that Li-ion batteries will become a dominant technology for PHEVs and EVs, it clearly gives a short-term advantage to Li-ion battery developers who can make products that will fit in a limited volume. I remain skeptical about whether Li-ion battery technology will ever be robust enough or cheap enough for widespread adoption in the automotive industry and I wouldn't be surprised to see the volume constraints relaxed over time to facilitate the substitution of flow batteries and advanced lead-acid batteries. Seriously, does anyone really care whether the ugly green box hiding behind the shrubs is 3' by 3' instead of 4' by 4'? For the time being, the CES program favors Li-ion technology by imposing size constraints that have nothing to do with performance. It will be interesting to see how the program evolves as the cost and performance profiles for various battery technologies become clearer.

The use of solar power has be used for almost 200 years. In the 17th and 18th centuries people used to coat water storage tanks with solar absorbers so they can heat the water for showers.
The last time solar energy was in prominence was during the 70's during the last oil shock. At that time there were many tax incentives to install thermal solar panels used to heat water. The speaker at the conference stated that "These tax credits were one of the worst designed since people were actually able to make money on the credit by installing cheap and poor performing systems." This gave the entire solar industry a bad name during this time frame and it has taken over 20 years to overcome this tax dodge reputation.

SPACE AGE TECHNOLOGY - Solar cells, also known as Photo Voltaic Cells, were rapidly developed to provide electrical energy for space missions. The beauty of solar cells is that provided the Sun shines, they keep on producing free electricity. Well, sort of free. Solar panels are still expensive to manufacture. It is the high purchase price and installation cost that effectively limits their use.
There are many types of solar cell. Polycrystaline (more than one crystal), monocrystaline and thin film. Monocrystaline is presently the most efficient at converting light energy into electricity. Sometimes as high as 20% but more usually 15%. A monocrystaline cell is made from a thin slice cut from a single crystal of silicon. A grid of metal is then embedded over the wafer ending in the contacts and other layers added. Thin film cells are plated onto a plate of glass. They are much cheaper to produce, but only around 5% efficient and heavy. Vehicle designers will normally want to capture as much energy as possible for a given area and weight.

"What is often considered the first genuine solar cell was built around 1883 by Charles Fritts, who used junctions formed by coating selenium (a semiconductor) with an extremely thin layer of gold... These early solar cells, however, still had energy-conversion efficiencies of less than 1 percent. This impasse was finally overcome with the development of the silicon solar cell by Russell Ohl in 1941. Thirteen years later three other American researchers, G.L. Pearson, Daryl Chapin, and Calvin Fuller, demonstrated a silicon solar cell capable of a 6-percent energy-conversion efficiency when used in direct sunlight." - Encyclopedia Britannica

The £6.3million PV-21 programme will focus on making thin-film light absorbing cells for solar panels from sustainable and affordable materials.
The four-year project, which begins in April (2008), is being funded by the Engineering and Physical Sciences Research Council (EPSRC) under the SUPERGEN initiative.
Eight UK universities, led by Durham and including Bangor, Bath, Cranfield, Edinburgh, Imperial College London, Northumbria and Southampton, are involved in the project.
They will work together with nine industrial partners towards a "medium to long-term goal" of making solar energy more competitive and sustainable, particularly in light of the recent rise in fossil fuel prices.
At present solar cells -- used to convert light energy into electricity - are made from key components such as the rare and expensive metal indium which costs approximately £320 ($660) per kilogram.
Research Project Aims To Make Solar Energy Technology Cheaper
ScienceDaily (Jan. 17, 2008) — A national team of scientists led by experts at Durham University are embarking on one of the UK's largest ever research projects into photovoltaic (PV) solar energy.

­You've probably seen calculators that have solar cells -- calculators that never need batteries, and in some cases don't even have an off button. As long as you have enough light, they seem to work forever. You may have seen larger solar panels -- on emergency road signs or call boxes, on buoys, even in parking lots to power lights.
Although these larger panels aren't as common as solar powered calculators, they're out there, and not that hard to spot if you know where to look. There are solar cell arrays on satellites, where they are used to power the electrical systems. Yo­u have probably also been hearing about the "solar revolution" for the last 20 years -- the idea that one day we will all use free electricity fro­m the sun. This is a seductive promise: On a bright, sunny day, the sun shines approximately 1,000 watts of energy per square meter of the planet's surface, and if we could collect all of that energy we could

­Silicon has some special chemical properties, especially in its crystalline form. An atom of sili­con has 14 electrons, arranged in three different shells. The first two shells, those closest to the center, are completely full. The outer shell, however, is only half full, having only four electrons. A silicon atom will always look for ways to fill up its last shell (which would like to have eight electrons). To do this, it will share electrons with four of its neighbor silicon atoms. It's like every atom holds hands with its neighbors, except that in this case, each atom has four hands joined to four neighbors. That's what forms the crystalline structure, and that structure turns out to be important to this type of PV cell.
We've now described pure, crystalline silicon. Pure silicon is a poor conductor of electricity because none of its electrons are free to move about, as electrons are in good conductors such as copper. Instead, the electrons are all locked in the crystalline structure. The silicon in a solar cell is modified slightly so that it will work as a solar cell.

They say hope floats. Israel’s premiere environmental architecture firm Geotectura has certainly taken this statement to heart. Joseph Cory a designer at Geotectura, has worked with an aerospace engineer, to develop floating solar balloons capable of collecting solar energy in crowded cityscapes and places where large solar panels are not a viable alternative. They hold potential for disaster-stricken areas as well.
Filled with helium and coated with a space-age fabric made from photovoltaic solar cells, this project called SunHope is a promising low-cost system that could collect solar energy with less environmental impact than other traditional solar energy solutions.
Traditional solar systems, report Inhabitat, have daunting barriers to entry: they require high initial investments, large land requirements, and an in-depth installation process. On the other hand, the Sunhope project can go around these problems by constructing low-cost photovoltaic arrays designed for vertical rather than the horizontal spac

Also ideal for off-grid applications, these solar energy balloons could power tribes in the middle of the desert, people living in isolated islands; they can be connected to ocean-bound freighters, power homes in heavily forested areas; and since they are easy to deploy, we imagine they could offer quick power relief opportunities in disAlso ideal for off-grid applications, these solar energy balloons could power tribes in the middle of the desert, people living in isolated islands;
they can be connected to ocean-bound freighters, power homes in heavily forested areas; and since they are easy to deploy, we imagine they could offer quick power relief opportunities in disaster stricken areas.aster stricken areas.Several prototypes have been developed to show that a 10 ft balloon could provide about a kilowatt of energy roughly equal to about 25 square meters of solar panels. The cost? About $4,000 per balloon, compared to the $10,000 for a solar field. With the rising costs of electricity in Israel and the world (our bill is the highest it has ever been this month), we can hardly wait until SunHope starts production. This Green Prophet would be a buyer for