The energy which is generated in the Sun’s core takes about a million years to reach the surface, and every minute, the Sun is getting lighter. The Sun has been active for a staggering 4.6 million billion years, and is expected to go on for another 5 billion years. Towards the end, it will fuse helium into heavier elements, this will make it swell up and grow so large that it will swallow up the Earth. It will then collapse into a white dwarf, and take a trillion years cooling down.

Right now, the Sun is a yellow dwarf, and stands at the centre of our solar system. Everything else – the planets, the asteroids, the meteoroids, etc. orbit the Sun. The distance between the Sun and the earth is almost 149,600,000 kilometres. The light from the Sun supports the process of photosynthesis, and is also responsible for our climate and weather. There is hydrogen on the Sun’s surface, which amounts to 74% of its mass, and 92% of its volume. There is also helium, which accounts for 24% mass, and 7% volume. Finally, there are traces of other elements, like silicon, sulfur, neon, calcium, chromium, magnesium, carbon, iron, nickel, and oxygen. The surface of the Sun often looks white, because of the process of atmospheric scattering, and appears to be yellow when seen from the earth’s surface.

The Sun is responsible for giving is sunlight, which is our primary source of energy. The amount of power per unit area deposited by the Sun, (areas which are directly exposed to sunlight) is called the solar constant. Plants undergo the process of photosynthesis, which takes the sunlight and converts it to oxygen and reduced carbon compounds. We, on the other hand, have developed solar cells, which capture the sunlight and convert it to electricity, or perhaps something else that comes in useful.

Sunlight has ultraviolet rays in it, which is sometimes used for the sanitization of tools and water, due to its antiseptic properties. However, it can also be responsible for sunburn, and has been known to produce Vitamin D. The Sun is actually a star that is magnetically active. A strong, dynamic magnetic field is supported by it, and this changes from year to year, and changes direction every eleven years, around the solar maximum. Though we have learnt a lot about the Sun over the years through constant research, many questions remain a mystery – like the origins of flares, the regular cycle of sunspot activity, etc.

The pool itself is the storage place for the system and the pump that is usually used for filtering the water also circulates water through this solar heating system. A collector is the most important part of these systems. A typical collector is a set of plastic panels which have large headers on its top and its bottom, this collector is strapped to the roof at both ends. So during the day when the filter works, the water is first sent through the solar collectors before they are returned back to the pool area. These systems are usually efficient enough to heat large amounts of water every day and then returns the water to the pool, after increasing the temperature by two to five degree Fahrenheit.

More than seventy percent of the heat generated by the pool is lost due to evaporation, and installing such solar pool heaters which includes a pool cover is the most economical step to take to control the temperature of the swimming pool. These covers are also helpful in keeping the pool clean and maintains the usage of chemicals.

It is basically the most effective method to reduce loss of heat, evaporation of water and use of chemicals. The amount of collector area required is from fifty to hundred percentage of the pool. This depends on the user’s requirements and also the site and the collector efficiency. The best method of using the solar collector is by tilting it to the south to a degree of twenty to thirty two. Indoor pools which are going to be used the whole year would require glazed and flat collectors, which should ideally be tilted to an angle of thirty five to forty degree. Roof types and pipes could cause interference for these collectors. In such cases these collectors can be mounted on the ground on a frame next to the pool.

Most of these pool collectors must be drained fully when it is not in use as freezing conditions can cause damage to these collectors. All plumbing which is connected to it must be drained back when the pool isn’t in function.

An average system can cost an interested party from anything between $2000 to $4000, depending on the area of the collector and also the installation charges.

Solar collectors are usually placed on tops of roofs but need not necessarily face the sun. They are angled however according to the latitude of the area where it is being placed.

A solar thermal collector more particularly is called the batch systems. The other kinds of collectors do not usually store the energy, they usually use fluid circulation such as water to transport the heat energy to serve the purposes of heating etc.

How it works is that the collector directly captures the solar radiation using a dark colored surface to absorb this as heat and then transfer it to the carrying fluid. This fluid used is usually water since it has a high thermal capacity. Metal serves the purpose of the conductor, especially metals such as aluminum and copper. Usually these collectors are coated with the kind of metal which would have properties of high absorption but are low on emission.

There are various kinds of these solar collectors. The Heat Pipe Solar Collector for example, is reliable and efficient. It uses red copper pipes, whereby the water gets heated by these pipes quickly. Since there is no water allowed to enter in the vacuum tubes, there is no probability of bursting during the winters. The U Pipe Solar Collectors are ideal on the other hand for pitched or even flat roofs. Here, the vacuum tubes absorb the radiation and transfer it into heat energy and then the energy is passed into the U pipes. The Non-Pressure Solar collector is by far the safest and the most comfortable to install in hotels or schools or other large areas. It is both economical and efficient, and it can supply large amounts of hot water. Another kind of solar collector is the Flat Plate Solar Collector. It uses copper and aluminum composite plates for its system which increase the absorption rates of the device. These are usually extremely solid structures and come in such designs as the anti-typhoon design which is also very efficient. Residential or small-time commercial buildings that need to maintain below two hundred degree Fahrenheit typically use these Flat Plate Collectors, on the other hand, those buildings that need temperatures more than this can use the Evacuated Tube collectors.

We need to find portable energy, to conserve energy. Solar energy is the answer, and solar batteries will help us go a long way. It allows us to use natural resources, and the benefits are numerous. Solar chargers can travel with you anywhere you go. For instance, you could be climbing some hill with your friends, and your phone runs out of charge. In such situations, you could harness solar power and use a solar charger to increase your phone’s battery. So you see, solar chargers are extremely convenient, and not just portability-wise. You are also spending much less, you won’t have to spend lots of dollars of your hard-earned money buying multiple adaptors for international outlets. The same solar charger is guaranteed to work in any country. Also, another benefit is that you won’t have to buy multiple charging devices to power all the various electrical equipment in your possession, because you see, one solar charger can be used for almost all your small electrical devices!

As a traveler, you can use a solar charger to charge your batteries. You can also charge your radios, laptop computers, and MP3 players through it. You can add accessories to it, the possibilities are truly endless. Don’t make the mistake of thinking that they are difficult to operate, they are extremely user-friendly. All you need to do is just set it in the sun, and plug it into your device. In fact, solar energy as a technology has actually been around for quite a few years. But with lots of research and development, solar chargers are fast emerging as a great option. Today, they have evolved massively, and with a single solar cell panel, you can charge your batteries and your electrical devices.

So what are the benefits of solar batteries? Firstly, they are extremely clean, and do not pollute the environment. They are quiet, and user-friendly. No fuel is consumed, therefore no waste is given off. Also, you will not have to deal with unnecessary noise, because no mechanical parts are in motion. In fact, all you need to do is just place the sonar panel in the sun, and electricity is generated! Yes, it’s really as simple as that. In fact, solar charges maximize battery life, and generate pure DC electricity when exposed to sunlight. This is what your batteries need and want. You are preventing them from repetitive deep discharges which potentially shorten their life. Instead, you are saturating the lead plates with pure DC electrons. Also, you will be able to charge whenever you want, wherever you want, as long as there is sunshine.

The second type is the Evacuated Tube Collectors. The collector is constructed through double layer borosilicate glass tubes, these are evacuated for the purpose of providing insulation. The inner tube’s outer wall is coated with selective absorbing materials. This assists in the absorption of solar radiation, and thus the heat is transferred to the water, which is flowing through the inner tube.

Using solar water heaters will help to benefit the environment, as the technology is quite mature today, having undergone much research. People can stop using conventional forms of energy for heating water in factories, residential homes, and other commercial establishments. The market for solar water heaters, too, has been steadily increasing. Solar water heaters can provide hot water at temperatures of 60-80 degrees, for restaurants, hospitals, homes, etc. The heaters which have a capacity of 100-300 liters, are quite suitable for domestic applications. However, one can install the larger systems in guest houses, hotels, etc.

So what about the fuel savings? Well, you’ll be astonished to know that a solar water heater of 100 liters capacity can replace even an electric geyser, and 1500 units of electricity are saved every year! And what about the environment? The solar water heater (of 100 liters capacity) prevents emission of 1.5 tonnes of carbon dioxide annually. The life of a solar water heater is approximately 15-20 years. The beginning investment for a solar water heater is somewhat high, initially, compared to more conventional fuel alternatives, but the returns on the investment are quite good, because prices of conventional forms of energy are rapidly rising. The period of payback, however, depends on many factors. These are the pattern of utilization, the fuel replaced, and the site of installation.

Solar water heaters are really easy – they are made up of thermal collectors which are covered with dark glass, and a fluid system that allows the heat to move from the collector to the point of usage. Lastly, there is a reservoir that stocks the heat water for its use. Such systems can be used to heat swimming pools, or for domestic purposes. Solar water heaters use solar power to give thermal energy in order to provide hot water. Such systems can save lots of energy, as well as cutting down on utility costs. Plus, the energy produced is absolutely clean. Even in the northern climate, with a cold winter sun, solar water heaters can bring a 40% reduction in the electric bill.

In a gist, photovoltaic cells are responsible for producing electricity from sunlight. The photovoltaic modules are connected electrically in multiples, as solar photovoltaic arrays, and this converts the sun’s energy to electricity. The photos from sunlight turn the electrons into a higher condition of energy, and this creates electricity. The kind of electricity produced is DC electricity – direct current electricity, this is used to power equipment, or even for battery recharging. Initially, photovoltaic energy was used to power satellites that were orbiting, and for other kinds of spacecraft. However, with better technology, today it is used in grid connected power generation. However, the DC power needs to be changed to AC power, so an inverter is needed. Off grid power is also required in roadside telephone booths, remote sensing, and remote dwellings.

Since the cells need to be protected from the environment, they are kept tightly behind a sheet of glass. When larger amounts of power are required, then the cells are connected together, electrically, and form photovoltaic modules, these are also called solar panels. One single module by itself can give sufficient power for an emergency telephone, but in the case of a power plant, or a house, it is required that the modules must be arranged in arrays. Spain, in 2008, installed almost 50% of all photovoltaics.

It is estimated that by the year 2030, solar photovoltaic systems will probably be generating 1,864 GW of electricity, all around the world. This means high energy efficiency, and almost 14% of the population of the world would be satisfied by the solar power produced globally in about 25-26 years’ time. There are many advantages of solar photovoltaic energy. Firstly, the 89 petawatts of sunlight, which reaches the surface of the earth is quite enough, considering that humans consume, on an average, 15 terawatts of power. Also, solar energy, or photovoltaic energy does not cause pollution. So there is no waste or emission. Minimum maintenance and intervention is required, after the facilities are initially set up. Also, as a form of energy, photovoltaic energy is superior, economically, where fuel transport is always expensive and difficult, and in some cases, even impossible. The cost of operating a solar plant is quite low once the plant has been built.

Solar electricity, which is grid-connected, can be used locally. This reduces the losses incurred in transmission and distribution. However, it’s important to remember that not much research has been done on photovoltaic energy, so there is much scope for improvement.

In 2002, Sheffield Hallam University reported research that they had achieved the highest efficiency for solar cells, based on thin films of CdTe – 18%. However, NREL, the renewable energy research institute, had achieved 19.9% for solar cells, which were based on copper indium gallium selenide thin films. Of course, there are other ways to increase the efficiency of solar cells. For instance, there could be surface restructuring in order to reduce reflection loss. The cell surface would be constructed in the form of a pyramid, this would mean that incoming light would hit the surface many times. The new material used could be cadmium terruride (CdTe), copper indium selenide (CuInSe²) or even gallium arsenide (GaAs)

Also, various semiconductor materials (suited to various spectral ranges) could be arranged on top of each other, this is would help the scientist to use a wide spectrum of radiation. Another possible method is to use mirror and lens systems – which would focus higher light intensity on the solar cells. In this method, there is direct radiation. In the MIS Inversion Layer Cells method – a p-n junction does not produce the inner electrical field, but it is produced by the junction of a thin oxide layer, to a semiconductor. Light absorption could be increased and highly improved by using electrochemical liquid cells with titanium dioxide and electrolytes and dye.

Solar cells could be today’s answer to eliminating the harmful and poisonous side-effects of fossil fuels. However, there is a cost involved, and it is rather high. Some think that it is a luxury, rather than a necessity to save the environment. There are many ongoing projects which aim to increase the efficiency of solar cells. One such project in Germany aims to optimize the growth of silicon nanorods on inexpensive substrates. Cost-friendly substrates like glass or synthetic foil are being used. Nanorods that have the ability to act as good light-traps are being produced, these capture the light effectively, and transform it into electricity.

There is an urgent need to find more ways to generate electricity through solar cells, and therefore to make them more efficient.

The University of Delaware has been instrumental in its efforts by creating a high-performance crystalline silicon solar cell platform. The combined solar cell efficiency is a record breaking 42.8 percent. It’s particular important since it is at approximately 20 times magnification, at low concentration. It has high portability, so one can use it on a laptop computer.