Solar Water Heaters and its Benefits
Posted by admin on Jul 11, 2011
Solar Water Heaters and its Benefits
Instead of using the electromagnetic properties of sunlight, a solar water heater also known as solar boiler makes use of the heat provided by the sun. To capture this heat, a solar collector is mounted facing the sun. The captured heat is stored in tubes, which are filled with a special fluid of high thermal inertia. The heated fluid is transported through a submerged heat exchanger, which gives off the solar heat to the water in the reservoir. When hot water is requested, a series of sensors determines whether it is necessary to use conventional means to add some additional heat to the water.
Instead, water is circulated through the natural process of convection. Passive systems usually feature a solar collector that is directly connected to a water reservoir. Such a so-called “open loop system” is cheap and reliable, but it does have its disadvantages. First of all, it is unusable in climates where temperatures drop below zero. Since freezing water expands in volume, parts of the solar collector holding water will burst. Secondly, a passive open-circuit system has the tendency to work in reverse in periods where the water in the collector is colder than the water in the reservoir. In effect, heat from the reservoir will then be used to heat the water in the collector. Passive systems are generally only recommended in warmer climates.
Since the sun doesn’t shine all-year round (or all day for that matter), it is often necessary to have a back-up system. Such a system makes sure that water in the reservoir is kept at a minimum temperature to prevent the growth of dangerous legionella bacteria. Additionally, a backup system ensures that hot water is available during hours of no sunshine. A typical backup system is a normal water heater that uses mains electricity or gas to heat the water. In most cases, your present water heater will suffice as a backup system, although there are situations in which it might be beneficial to have a new system installed. Consult your local installer for personal advice on your particular situation.
The heated water in the reservoir can also be used to feed central heating conduits. Use of such a system is however limited, since days of bright sunshine are generally days in which you require less heat generated. Unless you want to run your radiators at full power in the summer, it is far more beneficial to use the solar hot water for hygienic and cooking purposes.
Facts about Solar Collector
Posted by admin on Jun 28, 2011
Facts about Solar Collector
The most basic and most common type of solar collector is the flat plate solar collector. At the heart of this collector you will find a sheet of thermally conductive dark material (usually metal) which absorbs as much sunlight as possible. Directly below this sheet a series of water conduits is found; the heat collected by the absorber is absorbed into the water and subsequently carried away by water flow. The collector is housed in an insulating box, with a glass plate on top to further insulate and heat the system. Due to their flexibility, relatively low costs and ease of installation, flat-plate collectors are often used in solar water heating systems.
Evacuated tube collectors consist of a parallel row of evacuated glass tubes. Within each tube, another glass tube is placed, which is covered in a strongly absorbing material. Since the evacuated space blocks both convection and conduction, the absorbed heat has little means of escape. The temperature within the tube itself can therefore reach extreme values, with temperatures of 170 °F to 350 °F commonly achieved. An inherent advantage of the evacuated tubes, is that their cylindrical form means that the collector is always perpendicular the sun. A disadvantage to this system is that sunlight shining in between the tube sis not captured. This can be partly countered by adding a reflective film to the back of the collector. Another disadvantage is cost: evacuated tube collectors are approximately twice as expensive as their flat-plate counterparts.
A solar collector is a device which captures as much sunlight as possible, in order to either redistribute or absorb it into a transport medium. Solar collectors are generally used to generate heat, although in some cases a parabolic dish is used to focus sunlight on a special high-temperature solar cell. The heat generated by a solar collector can be directly used to heat another object or can be indirectly used to generate electricity by driving a steam turbine. Solar collectors come in a large variety of shapes, sizes and purposes. Here, we will introduce you to the most commonly used types of solar collectors. These include the solar collectors commonly seen in solar water heaters.
Solar collectors therefore are important devices to capture the required heat in order to distribute it to specific medium in order to produce enough energy that will later produce electricity. Looking for some renewable energy sources is important to solve different problems we are dealing with nowadays with especially to energy consumption.
Produce Electricity through Solar Energy
Posted by admin on Jun 21, 2011
Produce Electricity through Solar Energy
Solar power is electricity generated from the levels of natural energy contained within the sun’s rays also known as solar radiation. The sun has been in existence for billions of years. Everyday, the sun shines down on our earth, shooting its solar energy in our direction. This solar energy is commonly known as solar radiation, and contains a significant amount of energy we are able to harness.
The sun’s rays contain photons. These photons are capable of transforming electrons into conduction electrons, which means they are able to carry an electrical charge.
The answer to the question of how do you produce electricity from solar energy is fairly easy to understand once you have a slight knowledge of the subject.
The solar panels are made of a semi-conductive material, the most common material is silicon.
The semi-conductive material contains electrons which are quite happy just sitting there.
When photons (contained within the sun’s rays) hit the solar cells, the electrons absorb this solar energy, transforming them into conduction electrons.
If the energy of these photons is great enough, then the electrons are able to become free, and carry an electric charge through a circuit to the destination.
Any electrons that do not receive enough energy simply warm up, which heats your cell or panel, resulting in lowering the efficiency of the cell.
The more solar cells contained in a solar panel, or solar array, means the more output you will receive.
The lowering in efficiency is down to two main factors and they are; that the cell is not working to its full potential, the second factor is when the electrons release heat, the panel also becomes warm, interfering with other aspects of the solar cells.
Quality cells are also a major factor in efficiency. If you purchase more expensive natural energy technologies, you are more likely to have a more efficient cell.
Another factor which affects solar panel efficiency is location. Obviously nearer the equator, you will receive a slightly better output with a given cell, but solar cells should always be facing the direction of the sun, and have no objects blocking the sun’s rays.
It is really amazing that from natural energy sources, we can able to produce electricity that will be useful to our homes and businesses. It is a wise thing to understand and develop all natural energy sources as a solution to many environmental problems and by utilizing solar energy, it can be a solution to a higher electric bill consumption that we are experiencing nowadays.
The Truth about Solar Energy
Posted by admin on Jun 8, 2011
Solar energy is the energy coming from the sun.There are two types of solar energy- the thermal energy and electric energy. Thermal energy heats the earth, our body and even our homes. Electric energy on the other hand uses the energy of the sun to produce electricity also known as photovoltaic’s. With the high cost of electric bill, we must find solution to this problem as our used of energy increases each day.
Why we have to switch for solar energy:
Like any other any sources, solar energy has advantages and disadvantages upon using it. Solar energy is a completely renewable resource. This means that even when we cannot make use of the sun’s power because of nighttime or cloudy and stormy days, we can always rely on the sun showing up the very next day as a constant and consistent power source. Solar energy creates absolutely no pollution. This is perhaps the most important advantage that makes solar energy so much more practical than oil. Oil burning releases harmful greenhouses gases, carcinogens and carbon dioxide into our precious air.
Very little maintenance is required to keep solar cells running. There are no moving parts in a solar cell, which makes it impossible to really hurt them. Solar cells tend to last a good long time with only an annual cleaning to worry about.
Solar power technology is improving consistently over time, as people begin to understand all of the benefits offered by this incredible technology. As our oil reserves decline, it is important for us to turn to alternative sources for energy.
Disadvantages of Solar energy:
Pollution can be a disadvantage to solar panels, as pollution can degrade the efficiency of photovoltaic cells. Clouds also provide the same effect, as they can reduce the energy of the sun’s rays. This certain disadvantage is more of an issue with older solar components, as newer designs integrate technologies to overcome the worst of these effects.
One of the main disadvantages is the initial cost of the equipment used to harness the suns energy. Solar energy technologies still remain a costly alternative to the use of readily available fossil fuel technologies.
Solar energy is only useful when the sun is shining. During the night, your expensive solar equipment will be useless; however the use of solar battery chargers can help to reduce the effects of this disadvantage. A solar energy installation requires a large area for the system to be efficient in providing a source of electricity. This may be a disadvantage in areas where space is short.
Solar energy is one of the greatest achievements of mankind that offers a great advantage in the future. It might be a disadvantage at some point, the advantages it offer is even greater for it is a readily source of energy.
The benefits and drawbacks of Solar Panels
Posted by admin on May 20, 2011
Technology in any form always has its accompanying benefits and inherent problems; even clean and green ones like solar panels have them. Before deciding to make the switch, it is good to know more about the pros and cons of using solar panels to see if it will fit into your lifestyle or not. At the present growing trend, fortunately, more and more people are now making use of solar panels in their homes and businesses because its good points far outweigh its bad points.
Advantages of Solar Panels:
· Solar panels do not cost you much money. With the exceptions of purchasing and installing your panels with the help of a contractor, you do not need to pay your power bills anymore because the electricity you get from the sun is totally free (If your panels are not big enough, at least your power bill expenses will be minimized). Any expenses you have from buying and putting up the solar panels can be easily recovered. If your solar power system is so efficient that you generate excess voltage, you can sell this to the power companies and earn income. This practice is called net metering. The government can also both help lower the cost of buying your solar panels and can allow you to invest money in them. This is done through grants and incentives being given to those who make the switch to alternative sources of energy in their private places.
· Since it gets its energy directly from the sun, solar panels do not need to consume and burn fuels like coal and oil. Therefore, you are not affected by the rapid increase of fuel prices in the international market.
· It is environment-friendly since it does not need to burn fossil fuels or use nuclear material to generate electricity. This avoids possible contamination of our air, water, and atmosphere with hazardous pollutants and greenhouse gases. The only pollution generated by solar panels is minimal and caused only by the process of manufacturing the said panels.
· Solar panels require only simple and very occasional maintenance. This means you only need to clean the panels with soap and water once in a blue moon.
Disadvantages of solar panels:
· The initial cost of installing the panels and the expensive nature of the panel materials can take some huge amount of cash from your wallet. Fortunately, this only happens once and the local government can give you grants and incentives to lower your pay amount and help you invest more money into your solar panels. Try also net metering if your panels will later provide more than enough electricity for your needs. The technology for making solar panels improves yearly and so its market price may lower significantly in the coming future.
· Solar panels do not work at evening because there is no sunlight. To compensate for this, attach storage batteries and charging systems into your solar power grid.
· Bad weather and accumulated dirt or air pollution can block out the sun and hamper the efficiency of your solar panels. Though the former cannot be prevented, the latter can be remedied by proper cleaning and maintenance. The panels should also be spread out through a wide area to get more sun and attain higher efficiency.
History of Solar Panels and Photovoltaic Phenomena
Posted by admin on May 18, 2011
The use of solar panels for generating electricity may be a relatively new concept, but then living things like plants have always used solar energy for their life processes. Humans have employed the sun for purposes such as drying seawater for salt, preserving food stuffs, and telling time in sundials. But in our present time, solar panels and power generation is probably the most important development in the field of solar energy, as we are now experiencing the two problems of electrical shortage and negative environmental changes.
Modern solar panels that make electricity are reliant upon the principles of photoelectrical phenomena. Specifically, it works upon the photovoltaic principle wherein certain materials generate voltage when exposed to ample light. Before and during the Industrial Revolution, the application of solar energy meant putting the sun’s heat to work in drying materials and, in one failed attempt, to create steam from water in order to drive machine turbines. In 1887, Heinrich Hertz discovered that certain metals greatly decreased their resistivity to electrical current when exposed to light. His contemporary, Henri Becquerel, noted in his experiments with early batteries that certain metals like selenium created electrical voltage when they were pulled out of the acid and put under intense sunlight. Other scientists like Willoughby Smith, Johann Elster, and Hans Geitel discovered interesting electrical behavior related to metals and light. However, most of these were treated as mere curiosities and were never used for power generation. Probably the only practical application for photoelectric devices at that time and the time prior to solar panels was in sensors and detectors that work when exposed to light (such as in camera light meters, light switches, automatic doors, etc.).
The way to efficient solar panels and solar electrical generation began when Werner Siemens did further research on Becquerel’s work on the photovoltaic effect. Later on Max Planck and Albert Einstein perfected Quantum Physics and described the Photoelectric Theory for the first time. Part of it described that when exposed to intense radiant energy (such as that from the sun), certain materials can release and transfer electrons from within, thereby possibly generating usable voltage. This new idea caught the interests of those who wanted to create electricity directly from sunlight. Another development was the coming of semiconductor materials like silicon. Semiconductors are more readily available than metals and generate voltage more efficiently when exposed to sunlight. By the 1960s and 70s, the modern form of solar panels were introduced and were first employed in powering up satellites and devices used for space exploration. The technology keeps on improving exponentially, with more efficient designs in the market that can produce enough voltage to power a building.
At present, many solar electric panels are still made from silicon and other semiconductors, but have increased voltage output due to improvements in the design. From being a laboratory curiosity to a power source for space satellites, they are finding more useful applications closer to home. Domestically, they can provide enough power for houses and thereby help the owner save money on power bills. Miniature gadgets like calculators and chargers can also be powered up by solar panels. Vehicles can prevent pollution and escape the fuel shortage by switching to solar panels. Even remote telecommunications units and isolated communities can power themselves up with solar panels instead of relying on cumbersome electrical wires from the power company. Indeed, our future may be founded upon the use of solar panels and their photovoltaic benefits.
HOW TO TAKE CARE OF YOUR SOLAR PANELS
Posted by admin on Apr 18, 2011
In taking care of our environment, we have tools to make things a little bit easier for us. But who takes care of our tools? Solar panels can get rusty and brittle without proper car. Each panel consist of grid of solar cells and glasses enclosed in the grid. The glass covering the grid may be strong enough to withstand any weather condition but can be thin enough to be sure that enough light can be filtered in. They need regular maintenance to protect their quality.
Some of the things we need to do in taking good care of our panels are:
1. Regularly check and monitor your panels. Make sure that there are no damage or dirt build up has on the glass or frame. Brush dirt or droppings from the panels. This loosens the grime before cleaning the panel.
2. Clean the surface area of the glass and frame with moist washcloth. Be sure to use mild dish soap for excessive dirt build up.
3. Dry the panels clean using clean soft cloth. Solar panels are most effective when they are clean. The dirt that is stuck in your panels may most likely prevent and filter the sun’s rays from reaching the grid.
4. Always check the wires and cables attaching to your panels. These wires may become loose due to wild weather conditions.
5. Shower your panels with water using a plant sprinkler twice or more times a year to clearly dust off the dirt. You can do this in the morning depending upon the weather condition.
6. If your panel is dirty, the amount of sunlight able to get through decreases and thus energy production decreases. Bird droppings and pollen affect the panel most often, so if you notice these on your panel rinse as soon as possible.
7. Inspect the panel while you are cleaning it for cracks in the glass. Solar panels most often malfunction because of water damage. If you notice any cracks, fill the crack with a high-temperature silicon seal
Solar panels consist of photovoltaic cells made of silicon, covered with a thick sheet of glass and set in an aluminium frame. Sunlight activates electrons in the cells which travel to a conversion box on the solar panel where they are converted to electricity. Some people claim that solar panels need no maintenance, but just a few hours of time devoted to the panel a year will keep it running efficiently and help it last longer.
Solar energy and benefits from the government
Posted by admin on Apr 8, 2011
With the current problems of environmental pollution and the looming energy shortage, many governments are now trying to encourage residents to use clean and renewable sources of power for their homes. Solar power is one of the most popular and easiest to use among the renewable forms of energy. In order for more people to switch to solar power, the government offers incentives to lower the cost of installing panels and other equipment for harnessing the sun’s energy.
These incentives for solar power come in different forms and may vary from each state or country. But no matter what the form, the ultimate goal is to lower the cost of using alternative energy so as to motivate others to make the switch. The most common of these incentives is tax cuts or tax reductions. Anyone who purchases a solar power system or borrows money to buy a solar power system can be able to deduct some percentage from their property tax or their loan interest. In some states, total property tax exemption is given for those who buy solar panels. Also related to tax cuts are tax credits. The federal government gives 30% tax credits to those who begin using alternative power sources. A 50% depreciation allowance is provided together with this.
Apart from tax-related benefits, governments provide another kind of incentive for the use of solar power. This is the grant. A grant allows a person to buy and install solar panels with reduced cost. This is because the government will not only reduce the property tax; it will also pay for a great part of the expenses involved in buying the panels. Technical assistance for the owner of the panels is another benefit provided for by the grant. But perhaps the most enticing benefit in the grant would be investment. The owner of the panels can earn money while powering up his home. This is done by selling the excess electricity generated by solar panels to the electric power providers. The government and the power providers will pay the panel users per watt sold. The electricity the acquired would be added to the voltage generated by the conventional power stations and then sent to the power grid. The rate of pay for the sold electricity varies from state to state.
Types Of Solar Collectors
Posted by admin on Apr 7, 2011
Solar collectors are designed to collect heat by absorbing power from the sun. It may vary from a simple installation used to heat air or water to something as complex as those used in solar power plants. Basically, collectors are used to convert into usable form the energy being given off by the sun. Solar collectors come in different packages depending on how it absorbs energy and the materials used for its construction. The most common solar collector being used is the flat plate collector type. This is the type that most people with a general and basic concept of solar energy and solar collectors are familiar with. Flat collectors are normally placed on rooftops for maximum absorption of sunlight. One example of this collector is the one seen in solar powered calculators and the ones that are attached on certain models of cellular phones. Flat plate collectors work by sandwiching a system of absorber pipings between two flat plates. These pipings are the ones largely responsible for the absorption and conversion of energy into usable form. There is still ongoing effort to improve the quality of flat plate solar collectors especially with the kind of material being used for the plates, this is to improve absorption during those times when the sun is not so visible like during winter.
Another type of solar collector is the evacuated tube collector. These collectors are more efficient than its flat counterpart when it comes to reducing heat loss either by convection or conduction. Tube collectors are more suited in areas or places with a cold climate and can produce or retain more heat than flat plate solar collectors. However, this type of solar collector is more expensive and there is still the question of its durability and life span.
Comparisons are not unusual for these two types. It is just but natural that consumers would want the best and more efficient one to power their homes or businesses. But once all the cards are down, one could see that there is no single best type to fit all needs and purposes. Each one has its own advantage and disadvantage over the other. This is why careful survey is still needed before choosing and installing a solar energy system. Certain factors like climate, availability of sunlight, energy consumption of the house or business and overall cost of solar collectors affect the decision on what type of collector would best fit ones’ needs.
Solar Collectors
Posted by admin on Apr 6, 2011
Solar collectors are designed to collect heat by absorbing power from the sun. It may vary from a simple installation used to heat air or water to something as complex as those used in solar power plants. Basically, collectors are used to convert into usable form the energy being given off by the sun. Solar collectors come in different packages depending on how it absorbs energy and the materials used for its construction. The most common solar collector being used is the flat plate collector type. This is the type that most people with a general and basic concept of solar energy and solar collectors are familiar with. Flat collectors are normally placed on rooftops for maximum absorption of sunlight. One example of this collector is the one seen in solar powered calculators and the ones that are attached on certain models of cellular phones. Flat plate collectors work by sandwiching a system of absorber pipings between two flat plates. These pipings are the ones largely responsible for the absorption and conversion of energy into usable form. There is still ongoing effort to improve the quality of flat plate solar collectors especially with the kind of material being used for the plates, this is to improve absorption during those times when the sun is not so visible like during winter.
Another type of solar collector is the evacuated tube collector. These collectors are more efficient than its flat counterpart when it comes to reducing heat loss either by convection or conduction. Tube collectors are more suited in areas or places with a cold climate and can produce or retain more heat than flat plate solar collectors. However, this type of solar collector is more expensive and there is still the question of its durability and life span.
Comparisons are not unusual for these two types. It is just but natural that consumers would want the best and more efficient one to power their homes or businesses. But once all the cards are down, one could see that there is no single best type to fit all needs and purposes. Each one has its own advantage and disadvantage over the other. This is why careful survey is still needed before choosing and installing a solar energy system. Certain factors like climate, availability of sunlight, energy consumption of the house or business and overall cost of solar collectors affect the decision on what type of collector would best fit ones’ needs.