Sunday, 13 November 2011

Energy Saving Myths

Myth #1: Closing the Vent Saves Energy

Though it seems that closing vents in unused rooms would save energy, the energy consumed by the system is at the unit itself, and restricting conditioned air at a vent termination redirects it to other locations in the house or through leaks in your duct system. Closing vents also puts backpressure on the fan that pushes the air through the system, causing it to work harder, use more energy, and wear out faster.

Tuesday, 8 November 2011

How To Save Heating Costs - Practical Tips

Saving energy is easy to do but it requires one to take action.

Here are a series of no or low cost heating tips you can implement to save yourself money and reduce CO2 emissions. As yo can see, it is not very difficult to get a much more energy efficient home heating situation!

Consider implementing some of the following no or low cost heat energy saving strategies:

Monday, 24 October 2011

Geyser Efficiency – blankets, pipe insulation and timers can result in lower electricity bills

Some of us more cash strapped individuals know where the geyser switch is so that we can turn it on and off during the day. But this supposedly clever idea can turn out to be rather frustrating when we forget to turn the geyser back on, which results in a cold shower and a miserable individual.

Geysers supply us with hot water for daily chores and tasks that include washing dishes, our hands and ourselves. The way in which a geyser functions is relatively simple. The geyser consists of an electrical element that heats up when the geyser is on. This electrical element then heats the water up within the geyser, therefore supplying us with hot water for our home.

Tuesday, 18 October 2011

Solar Pool Heating

 If you have a pool, you know how much heating it can crank up your utility bill. Solar energy systems for pools offer an alternative method that will not devastate your bank account.

Solar Energy Systems for Pools 

When most people think of solar energy systems, they think of the large crystalline structures that are meant to collect a lot of solar energy in order to convert it into solar power. However, there are other uses for solar energy systems. One of the more ingenious uses for this technology is the use of solar energy systems for heating pools. By using solar power to heat your swimming pool, you can be sure that your morning swim will always be nice, comfortable and cheap.

Everyone has to heat their pool unless they are living in a tropical climate where the temperature doesn’t drop at night. Some people choose to purchase a pool cover, but these only work to limit heat loss versus actually heating up the water. Gas heaters work well, but the operating cost of a gas heater can really add up. A low initial cost can draw pool owners to gas heaters, but the charges over the life of the use of the pool can be appalling.

Monday, 17 October 2011

You Can Determine the Solar Efficiency of Your Roof

It is becoming more and more common to install solar panels on roofs in order to obtain green electricity, but not all roofs are equally suitable. Scientists from the University of Gothenburg, Sweden, have launched a tool that uses the actual conditions to determine the maximum possible magnitude of solar incidence -- in a whole town, a neighbourhood, or a particular roof. The scientists have surveyed Gothenburg in a pilot project.

"The roofs structures of a town may be more or less suitable for the installation of solar panels, depending on such factors as how much a particular roof is shadowed by surrounding buildings and vegetation, the gradient of the roof, and the angle of incidence of sunlight. It is now possible for the first time to determine how much solar energy a particular roof will receive during the year," says Fredrik Lindberg of the Department of Earth Sciences at Gothenburg University.

Sunday, 16 October 2011

Collect rain water, help the planet

For most of us, the rain that falls on our roof runs off into the ground or the sewer system. But if you're motivated to save a little water and re-distribute it on your lawns or plants -- or even use it for laundry, dishes or other interior needs -- collecting rainwater from your gutters' downspouts is a no-brainer.

If it's allowed in your state, that is. Utah and parts of Washington State have antiquated but nonetheless tough laws banning anyone but owners of water rights from collecting rainwater flowing off privately owned rooftops. Such laws are rarely enforced, however, and one in Colorado was recently overturned.

According to John C. Davis, writing in E / The Environmental Magazine, just about any homeowner can collect rainwater, given that the roof and gutters do most of the work. And since an inch of rain falling on a 2,000-square-foot roof produces some 1,200 gallons of runoff, one can harvest enough to supply all the water needs of a family of four for about two weeks. Of course, most of us would only use rainwater to irrigate our lawn or garden, and there should be plenty to go around for doing that in all but the most drought stricken areas.

Tuesday, 11 October 2011

LED Light Bulbs - Facts & FAQ's

LED lighting is the newest lighting option to traditional light bulbs. But how efficient are they really? How bright? And what is this fuss about their color? Below you'll get answers to the most common questions regarding LED lights

* How efficient are led bulbs compared to incandescent bulbs?
* Are bulbs with more leds brighter than bulbs with less?
* How does the brightness of led lighting compare to incandescent lighting?
* What do "cool white" and "warm white" mean, and what is CCT?
* What is the difference between a floodlight and a spotlight?

How efficient are led bulbs compared to incandescent bulbs?

The efficacy of the newer LED light bulbs is more than five times higher than comparable incandescent bulbs. In other words, led light bulbs use only about 20% as much electricity to produce the same amount of light. However, because led bulbs direct a larger percentage of light where it is needed, in many applications they are as much as ten times as effective as incandescent bulbs, reducing energy use by 90%.

Are bulbs with more leds brighter than bulbs with less?

The number of leds is not the determining factor of bulb brightness. Different types of leds vary greatly in size and light output. The most accurate indicators of the brightness of LED bulbs are the measured lumens or lux. Lumens measure the total amount of light output from a bulb. Lux measures how bright the light is on a surface at a specified distance.

How does the brightness of led lighting compare to incandescent lighting?

Led light bulbs are much brighter than incandescent or halogen bulbs of the same wattage, but led bulbs are not available in very high wattages. Thus, when replacing incandescent or halogen lamps with led lamps, more led lamps are often needed. For example, to replace one 100-watt incandescent bulb you may need two 5-watt or 6-watt led bulbs. Although you have more bulbs you are still using 85% less electricity.

What do "cool white" and "warm white" mean, and what is CCT?

The color (CCT) of our white bulbs ranges from a warm yellow white (2700K) to a cool blue white (7000K).

By comparison, a typical incandescent bulb has a CCT of 2800K. A typical halogen is a bit higher, maybe 3500K. Daylight white is 4500K and a cool white fluorescent is 6000K or more.

The human eye adapts to background light so that even a daylight white bulb will look slightly blue in a room illuminated mainly with incandescent bulbs. Similarly, an incandescent bulb will look very yellow or even orange in midday sunlight.

What is the difference between a floodlight and a spotlight?

Led spotlights output a narrower beam of light, typically less than 45 degrees wide. Most of the light from a spotlight is concentrated onto a relatively small area producing a bright spot. Led floodlights output a wider beam of light, up to 120 degrees, so the light from a floodlight is spread out over a much larger area.

Because the light is more concentrated, a spotlight will appear brighter than a floodlight but only within its narrower beam. A spotlight is more suited to illuminating objects and a floodlight is more suited to illuminating areas.

So now you know more about LED light bulbs and also knows more about how much energy they save compared to ordinary light bulbs.

Monday, 10 October 2011

How to use your existing geyser and add a solar heating system to it

We recommend thats you use your existing geyser and add a solar heating system to it. When your geyser next needs replacing, then upgrade to solar geyser.

How the conversion works.
Using a pumped system it is possible to convert your existing geyser. You will need one conversion jet, one pump and one Photovoltaic panel and of course the Evacuated Solar Panel.

What it involves :

1. Mounting a frame and evacuated solar vacuum tubes on your roof.
2. Adding 1 conversion jet to the your existing geyser outlet. This connects the evacuated solar panel to your geyser
3. Installing a low power DC circulating pump to move water from the hot evacuated solar panel to your geyser.
4. Installing the 10W Photovoltiac solar panels that produces power for the DC circulating pump.

Evacuated solar panels are sized according to the amount of hot water usage per day and the part of South Africa where the installation will take place. This is guided by the annual sunshine received in that area.

Radiation example : Durban has 30% less sunshine energy than Johannesburg, so would need a larger panel.

Visit our commercial site GreenerZA for a range of photovoltaic solar panels.

Thursday, 29 September 2011

10 ways to keep cool at home

Save energy this summer. It’s easy to keep your house cool without air conditioning. Employing a few basic environmentally friendly principals will help keep you cool and will help you save money.

1. Hot Air Out, Cool Air In

The most basic thing you can do to keep your house cooler without air conditioning is to keep as much sunlight out as possible and let cooler air in at night. During the day, keep windows, drapes, blinds or shades closed, especially on the southern and western sides of your home. If you have a porch, you can put up large plastic or bamboo shades to cut down on sunlight.

2. Windows

Use white or light colored window dressings to reflect light. You can also apply reflective slicks to windows to further cut down on light. At night, leave cabinets open as well, as they will store heat.

3. Be a Fan of the Fan

Moving air is cooler air. At night, place fans in windows to bring more cool air in. Ceiling fans can also make a big difference. In terms of cooling, even a one-mile-per-hour breeze will make you feel three to four degrees cooler. In terms of energy savings, if you run a ceiling fan full-blast for 12 hours, you will only spend about $10 a month in electricity. Ceiling fans have two settings, one to pull air up (for winter use), and the other to push air down. Make sure your ceiling fan is blowing down.

4. Turn Your Fan Into an Air Conditioner

Another easy way to cool your home without air conditioning is to place a bowl of ice or a frozen milk jug in front of one or more fans.

5. What’s Hot in Your Home?

It’s one thing to keep hot air and sunlight out; it’s another to identify the appliances in your home that generate heat. If you aren’t at home during the day, it is easier to simply shut off as many electric appliances as possible. If you spend more of your day at home, try to use heat-generating appliances only during the coolest part of the day.

Keeping your electronics on a power strip provides a quick way to “power-down” before leaving for the day.

7. Light Bulbs

Change incandescent bulbs for cooler fluorescent lights or LED lights. Turn off lights when not in use.

8. Humidity

Humidity makes a room hotter. Do laundry early or late in the day. Take showers or baths during the cooler times of day. If your bathroom, laundry room or kitchen has vents, use them. Invest in a dehumidifier if you live in a humid climate.

9. Insulate Your Attic

A well-insulated attic, especially when an attic ventilating fan is used, is one of the best ways to keep heat out of your home.

10. Landscaping

As you plan out landscaping for your home, be mindful of having deciduous trees, trellises and shrubbery on the southern and western portions of your home. Don’t place heat-absorbing rocks, cement or asphalt too close to the house.

With a small amount of planning, you are on your way to a cooler and more enjoyable summer.

Monday, 26 September 2011

Ways to use Solar Energy

Solar EnergyUse of solar energy, energy derived from the sun, has grown in popularity amid economic and environmental concerns about nonrenewable sources of energy. Solar energy offers a cleaner, fully renewable and sustainable alternative to fossil fuels. As use of solar energy increases, the cost of solar energy declines, leading to new commercial and consumer applications.

Making Water Available:

The need for safe, clean water remains dire in many parts of the world. In countries where villages are long distances from available water sources, solar energy powers water pumps that deliver water to remote residential areas. Water pumped via solar energy also irrigates crops and brings water to livestock. Solar energy can purify water by removing salt and other impurities, making it safe for drinking, cooking and other uses.

Heating and Cooling

Some households harness the sun's rays via solar energy panels to provide a portion of the household's heating and cooling needs. When 100 percent of the household's needs are met via solar power, that household is considered "off the grid"; that is, no longer dependent upon the area's electrical grid. Solar energy also heats water, both inside and outside of homes. Heating swimming pools via solar radiation ranks first among U.S. households in solar energy applications.

Cooling via solar energy costs much more than heating, as the energy is used to convert a contained liquid into a gas, then force it into a low-pressure situation, thus reducing its temperature. The cost of this process makes it prohibitive. Thus, solar cooling is rarely used in consumer applications.

Converting Radiation to Power

Radiation collected and converted to electricity can power everything from small appliances to entire households or businesses. Large-scale communications systems, such as satellite systems and television stations, often rely on solar energy for part or all of their power.

Other Solar Energy Uses

With increasingly interest in vehicles powered by something other than petroleum, solar energy offers an alternative fuel source. Some electric and hybrid cars, buses and other modes of transportation utilize energy derived from photovoltaic cells.

Today, consumer applications go beyond small appliances like garden lights, hair dryers and calculators to larger, more energy-intensive processes, like drying clothes and cooking. Solar energy dries fruits, vegetables, grains, fish and other foods for increased quality and nutrition.

Originally posted on ehow

How to Make a Solar Powered Oven

Solar ovens are not a new idea. Almost 200 years ago, the British explorer John Herschel used a solar oven to cook food while in Africa. Today, it is perfectly possible to make your own solar oven from a couple of boxes and some everyday household items. A cardboard solar oven can produce temperatures in excess of 230 degrees Fahrenheit, more than sufficient to boil water and cook a meal.

Things you'll need:
  1. 15-inch-square cardboard box
  2.  17-inch-square cardboard box
  3.  Aluminum foil
  4.  Glue
  5.  Scissors or knife
  6.  Masking tape
  7. Sheet of thick card
  8. Sheet of glass or acrylic plastic
  9. Newspaper or a small wooden block
  10. Stiff wire
Instructions:

  1. Close the top of the larger box. Rest the smaller box on top of it, in the center of the lid of the larger box, and draw around it. Remove the smaller box. The result is the outline of the smaller box drawn in the middle of the large box's lid. Cut around the line to create a hole in the lid of the larger box. When completed, the hole should be the same size as the smaller box.
  2. Open the larger box and cover the internal surfaces, including the remains of the lid, with aluminum foil. Glue the foil into place. Close the lid and glue the flaps into place so the lid cannot be opened. Seal around the edges with tape to form an air-tight seal.
  3. Open the lid on the smaller box. Line the box with foil, covering the entire surface apart from the lid. Fold the lid of the smaller box back on all four sides so the flaps stick out from the box.
  4. Place folded newspaper or a small wooden block in the base of the large box so that the smaller box, when lowered into the hole, rests on the paper or block. This supports the inner box when a pot is placed in it.
  5. Lower the smaller box into the hole and glue the lid flaps to the outer surface of the larger box's lid. The result is a large box with an inset smaller one.
  6. Create a reflector by cutting a sheet of card to the same size as the top of the larger box. Coat one side of the card in foil and glue the foil in place. Tape the bottom edge of the reflector to the back edge of the larger box so it looks like an additional fold-down lid.
  7. Bend both ends of two strips of stiff wire through 90 degrees to form two 6-inch-long staple-shaped metal supports for the reflector. Lift the reflector so that it stands vertically. Use tape to attach a wire prop on each side of the reflector about 3 inches above the hinged base. Tilt the reflector slightly forward from vertical so it reflects light down into the oven. Adjust the angle of the props to hold it in this position.
  8. Cut a sheet of glass or clear plastic to fit over the top of the smaller box. This acts as a see-through lid for the oven, trapping heat inside the box. Do not attach the transparent sheet to the box; it needs to be removed when adding or removing food from the oven.
Originally posted on ehow

    Friday, 23 September 2011

    Solar Energy -The Benefits

    The use of passive solar energy has had a role in building since ancient times. Growing concerns about how energy is generated makes passive solar energy even more important today. The amount of solar energy that reaches the earth's surface is currently 10,000 times the amount of energy consumed by the population of the planet, according to NASA. Passive solar energy provides lighting, heating and cooling without the need for energy production.

    Energy Savings

    Harnessing passive solar energy is the first step in creating energy-efficient buildings. Buildings that take advantage of the natural properties of the sun reduce the need for energy generated by modern technologies. Affective daylight reduces the need for artificial light during the day and passive heating and cooling reduce dependence on mechanical systems for comfort. Strategies for using passive solar energy are dependent on where a project is located. Passive solar buildings located in hot, humid regions take advantage of cooling strategies, while buildings in colder regions make use of solar heat gain.

    Cost Savings

    Mechanical equipment is costly to purchase and install. Using passive solar energy reduces the size of the equipment needed to maintain a healthy indoor environment and lowers the initial cost of a project. Harvesting passive solar energy requires little to no maintenance, making operational costs lower as well. Active solar systems degrade over time and are continuously outdated as advances are made in the industry. Passive solar energy provides an efficient alternative energy source throughout the life of the building. A lesser known cost in energy consumption is the cost it takes to physically move electrons from one place to another. This can be as much as 30 percent of the amount of energy purchased from a utility company. Passive solar energy uses direct methods of energy transfer and requires no transportation.

    Quality of Life

    Human biorhythms are disrupted by artificial environments which can create fatigue and reduce concentration. Exposure to daily and yearly natural cycles increases well-being and creates a healthier state of mind. Passive solar design creates buildings that depend on and incorporate natural cycles. The occupants of a passive solar building benefit from a direct connection to the natural environment.

    Wednesday, 21 September 2011

    Solar Ideas For Your Home

    The term "solar home" can apply to homes specifically designed to incorporate solar technologies, as well as to homes retrofitted for solar power. As the concern over the environmental effects of fossil fuels used in automobiles and for power production has grown, the interest in methods of using solar energy to reduce power consumption in the home has also grown. A number of solar technologies exist; for new homes, design elements can help to harness solar energy.

    Solar Panels


    Solar panels are one of the most widely employed types of solar technology applicable to homes. Easily recognized by the bluish-tinted panels, solar systems can employ several types of solar cell. The most efficient, and consequently most costly, type of residential solar panels are monocrystalline cell panels, made from silicon wafers cut from a single silicon crystal, reports Free Sun Power. Other options are polycrystalline cell panels---the most frequently used---and thin-film panels, which offer the lowest efficiency. Solar panels produce no carbon dioxide while used and can help reduce or eliminate the power costs of a home.

    Solar Water Heating


    You can integrate a number of solar water heating applications into a home. The Department of Energy reports that solar water heaters function, in general, by passing cold water through a solar collector to heat the water and then directing the heated water into a storage tank. Solar collector types include flat-plate collectors, batch systems and evacuated tube systems. Solar water heaters can be passive systems, in which gravity moves the water, or active systems that use pumps. Due to the potential structural forces involved, have such systems installed by experienced professionals.

    Design Elements


    Another type of passive solar is involves using the materials and design of a home to take advantage of the heat and light provided by the sun. Not every component of passive solar design will work for every environment. Homes in places that experience long winters with short durations of sunlight and extreme cold, such as Alaska, are better served with more traditional home designs. To take advantage of solar energy, orient the panels southward; southern exposure maximizes the amount of time the sun strikes the front of the home. Use materials that absorb solar energy on this portion of the home, along with larger windows, to help retain heat in the structure during the colder weather. Sustainable Sources reports that carefully designed overhangs can also shade these windows during summer months to help minimize excess heat.

    Monday, 19 September 2011

    10 Ways To Save Energy

    Saving energy may not build your character or change your clothing size, but it will save you some money and make a big difference for the environment.


    1. Get a power monitor. -- This small investment will give you a sense of how much power your home actually uses and which products are the biggest energy drains. In this case, knowledge is power, and it saves power.
    2. Be a turn-off. -- Don't leave electronics and appliances running when they're not in use. Leaving that computer on after a bedtime email check? Stop it! And turn the monitor off, too.
    3. Be a power stripper. -- No, really. Connect your electronics to power strips with on/off switches, and flip the switch when the products aren't in use instead of wasting energy on standby mode. Make it easy on yourself and put the power strip where you can reach it. If flipping the switch involves crawling behind your desk, this is going to be a hard resolution to stick to.
    4. Accept your products' intelligence. -- Newer electronics and appliances are great at self-regulating. Explore your computer's power management settings, the programmability of your heating or air conditioning systems, and the energy- and water-saving settings on your dishwasher and clothes washer. When it comes to saving energy, your household products may know more than you do. But don't worry; they won't tell anyone.
    5. Beware of overcharging. -- We all seem to have about a million chargers lying around. Mobile phone chargers, camera chargers, MP3 player chargers, etc. Instead of leaving them in the outlet in 24/7, plug them in only when they're needed. These little energy frenemies use power whenever they're plugged in, regardless of whether they're charging batteries or not.
    6. Stop living in the dark ages. -- Between dimmable compact fluorescents and affordable LEDs, lightbulbs have come a long way, my friend, and I see you over there, hoarding those incandescent bulbs. Quit dragging your heels. Buy the lightbulbs you wish to see in the world.
    7. Let your laundry chill. -- Most loads do just fine washed in cold water. In fact, many do better, since cold water doesn't set stains and is gentler on colored dyes. And yes, you guessed it: A cold water wash uses significantly less energy than a hot water one.
    8. Give your dishes some air. -- Your plates, glasses, and silverware are content to keep doing their jobs even without a daily hour at the sauna that is your dishwasher's heat dry setting. Do them and your wallet a favor by opening the dishwasher door and letting them air dry overnight.
    9. Stop the leaks. -- Drafts are leaks that even Julian Assange wouldn't defend. Whether it's the seal on your refrigerator door or the gaps around your windows, catch the culprits, and bring them to justice! Or at least fix them, so they stop doing that.
    10. Consult TopTen USA's lists. -- It's a fact of modern life that sooner or later, each of your appliances and electronics will need to be replaced. In 2011, when your refrigerator goes on the fritz, or your ancient dishwasher starts plastering all your plates with broccoli, or you simply can't stand that boxy old TV another minute, please don't forget to make energy efficiency a factor in your new purchase. A quick stop on www.TopTenUSA.org will give you all the information you need to make an informed and energy-conscious decision. You'll lower your bills and your impact on the planet, and that's a New Year's resolution we can all be proud of keeping.

    How to Install Water-Saving Shower Heads


    Water-saving shower heads have a fine spray that uses 2.2 to 2.5 gallons per minute (gpm), rather than the 3.5 to 5.5 gpm flow of older shower head models. Follow these steps to check and replace inefficient shower heads.

    Instructions:
    1. Check your existing shower heads to see how much water they use. Hold a plastic bucket under the shower head and fill it to the 1-gallon mark while checking the second hand on your watch. Divide 60 by the number of seconds it took to flow one gallon from the shower head to get the gpm output.
    2. Buy water-saving shower heads for any units that flowed a gallon in under 20 seconds. Look for the gpm rating on the shower head packaging and make sure it’s 2.5 gpm or less. You can buy pulsating or fine spray shower heads in low-flow design.
    3. Hold the shower water pipe firmly and use an adjustable wrench on the flat sides of your old shower head to loosen it by turning it counter-clockwise. Unscrew the old shower head all the way by hand and set it aside.
    4. Remove old white thread sealing tape from shower pipe threads. Wrap threads of shower pipe clockwise with new pipe thread tape starting at the open pipe end and overlapping about half a width of tape.
    5. Thread new shower head onto end of shower pipe and turn clockwise until hand tight. Turn on shower head to check for leaks. If water drips from top of shower head, carefully tighten the new shower head with an adjustable wrench, turning about ¼ to ½ turn clockwise.

    Installing a New Shower Head -- powered by ehow
    SolarSolutions: Suppliers of Water Efficient Shower Heads

    Government Lab Looks for Renewable Energy Solutions

    Saturday, 17 September 2011

    Prep Your Home For Solar

    home solar installation

    Solar is the future. Solar is on its way. It’s here, becoming more popular, accessible, and affordable as you read this. You may even be considering solar for your own home.

    It’s important to do the prep work in your home now, so you’re ready for that solar installation. Putting a new technology into an old setting can be like putting new wine in old bottles—and that, as you probably know, isn’t a great idea.

    “After all, it doesn’t make any sense to outfit a home with all of these great new, highly efficient technologies and then have it in a home that leaks like a sieve,” says Michelle Desiderio, Director of the Green Buildings program at the NAHB Reserch Center.
    How to get started?

    First, compare pricing on installation.


    Next, learn what you can do now to prep your home for the future of energy consumption: home solar.
    Heat Pump Water Heaters

    Heat pump water heaters have hit the residential market with a bang over the last few years. Why? They’re gaining popularity as a way to slash electric water heating bills—and save water and energy. Made by companies like General Electric, the heaters suck heat out of the air such as a basement or garage (like a fridge running in reverse) to help heat water in a house.

    The savings on this is astounding. Average operating costs of the device run between $225 and $280, or about half of standard water heaters.

    Not to mention the fact that the minute you turn on your warm water, it actually becomes warm. No running, running, running your water at full blast (five minutes of this equals the energy of about 14 hours powering a lamp) waiting for that hot water.
    Blown Fiberglass Insulation

    Rather than those old matted sheets, a new technique has been developed for insulation. Blowing fiberglass between the walls is one of the best ways to improve the efficiency of your home. Proper insulation makes sure that your energy isn’t simply leaking back out of your home.

    While the old sheets, or “batts” don’t often keep rooms sealed very tightly, a foam in the form of polyurethane provides better insulation, filling the nooks and crannies.

    But what about the fumes and chemicals, you ask? The fiberglass industry answered those needs by creating a fiberglass that can be blown into wall cavities. While there is still potential danger during a professional installation, the industry is continuing to improve the materials.

    And financially? Builders say that the blowing technique costs as much as 40% more than the batts, but it’s up to 50% cheaper than using spray foam. And better. Green building experts say that the higher insulation costs will at some point be offset by your overall savings in energy—dependent, of course, on what other green features the home has installed.

    Thursday, 15 September 2011

    PHOTOVOLTAIC Cost Review

    The installed capacity of photovoltaic modules has grown at a rate of 40 percent per year over the last decade. As the industry has grown, PV module prices declined along a well-established learning curve, which has seen cost reductions of 22 percent for each doubling of cumulative capacity over the last few decades. An excursion from this historical rate occurred due to supply bottlenecks and market dynamics from 2003 to the end of 2008. The learning curve has since returned towards the historic trend and the global installation capacity increased to 10 GWp/year in 2010.

    Both the IEA and the European Photovoltaic Industry Association (EPIA) expect further cost reduction with increased production capacities, improved supply chains and economies of scale. China has experienced a 20-fold increase in production capacity in four years, increased expansion of global production capacities for key components (including modules and inverters) and is continuing to exert downwards pressure on prices. A surge in silicon production capacity, a key commodity, has continued to increase, alleviating supply constraints. Technological cost reduction opportunities include improvements in efficiency for the different cell types. Based on these drivers, the IEA and EPIA have made cost projections using learning rates of 18 percent, slightly lower than the historical average of 22 percent.

    Read the full Cost review on Renewable Energy World

    Tuesday, 13 September 2011

    Tangled Coat of Nanowires Increases Solar Cell Efficiency by Absorbing More Light

    In the race to enhance the efficiency of solar cells, spending the time and effort to get tiny nanowires to line up neatly on the top of ordinary silicon wafers may not be worth the effort.

    An international team of researchers has for the first time demonstrated that random, haphazardly grown silicon nanowires can significantly boost the power-producing capabilities of solar cells by trapping a broad spectrum of light waves and capturing sunlight streaming in from a wide variety of angles.

    The nanowires, which are wrapped in a shell of silicon oxide, serve as an antireflective coating on top of the usually shiny silicon wafer.

    The scraggly tangle captures light ranging in color from red to violet, and the random orientation of the wires means the coating would continue to absorb light even as the angle of the Sun changes throughout the day.

    The researchers fabricated the jumbled, yet effective, antireflective coating by vaporizing silicon powder and then depositing it on top of a silicon wafer.

    The process, described in the AIP's new journal AIP Advances, is relatively inexpensive and could be scaled up for large manufacturing operations. For future work the team plans to create structures that are more ordered to test if the messy arrangement really is better.

    Originally posted on ScienceDaily

    Monday, 12 September 2011

    Photovoltaics among fastest growing industries in the world

    The tenth edition of the JRC PV Status Report indicates that in 2010, the photovoltaic (PV) industry production more than doubled and reached a world-wide production volume of 23.5 gigawatt (GW) of

    Since 1990, photovoltaic module production has increased more than 500-fold from 46 megawatts (MW) to 23.5 GW in 2010, which makes photovoltaics one of the fastest-growing industries at present.

    Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity. It is one of the most promising technological options to realise the shift to a decarbonised energy supply.

    Current solar cell technologies are well established with sufficient efficiency and energy output for at least 25 years of lifetime. This reliability, in addition to the increasing potential of electricity interruption from grid overloads, and the rise of electricity prices from conventional energy sources, add to the attractiveness of photovoltaic systems.

    In 2010, the world-wide photovoltaic production more than doubled, driven by major increases in Europe. For 2010 the annual market volume of newly-installed solar photovoltaic electricity systems varies between 17 and 19 GW, depending on estimates. This represents mostly the grid-connected photovoltaic market, as there are no reliable estimates available for the non grid-connected market. The report, published by the European Commission's Joint Research Centre (JRC) shows that with a cumulative installed capacity of over 29 GW, the European Union is leading in PV installations. By the end of 2010, European photovoltaic installations provided more than 70% of the total world-wide solar photovoltaic electricity generation capacity.

    The photovoltaic industry has changed dramatically over the last few years. China has become the major manufacturing centre for solar cells and modules followed by Taiwan, Germany and Japan. Amongst the twenty biggest photovoltaic manufacturers in 2010, only four had production facilities in Europe, namely First Solar (USA, Germany, Malaysia, Vietnam), Q-Cells (Germany and Malaysia), REC (Norway and Singapore) and Solarworld (Germany and USA).

    A special feature is the dramatic price reduction for solar modules by almost 50% over the last three years. This can be explained by the evolution from a supply to a demand-driven market and the resulting over-capacity for solar modules. Business analysts predict that investments in PV technology could double from € 35-40 billion in 2010 to over € 70 billion in 2015, while they expect prices for consumers to continuously decrease.

    Even with current economic difficulties, the number of market implementation programmes is still increasing world-wide. Examples of such measures to promote the use of PV technology include renewable portfolio standards, and feed-in tariff tax incentives. Coupled with the overall rising energy prices and pressure to reduce greenhouse gas emissions, this will continue to keep demand for solar systems high.

    In the long-term, growth rates for photovoltaics are expected to remain high. The study concludes that in order to maintain the high growth rate of the photovoltaic industry, different pathways have to be pursued. There is a need to reduce the material consumption per silicon solar cell because the cost of silicon is one of the main price factors of such solar cells. In parallel, the manufacturing of thin-film solar cells should be increased and the introduction of concentrated photovoltaics (CPVs) should be accelerated. Concentrated photovoltaics (CPVs) is a new technology which substitutes semi-conductor material with cheaper concentrating lenses, typically of plastics.

    Flexible way to use sun's rays

    Carl Harberger's 6,000-square-foot house in the Chatsworth neighborhood of Los Angeles is equipped with six refrigerators, five TVs, a smattering of computers and a pool, among other things - enough to draw the wagging finger of the eco-minded if it were not for what Harberger has on his roof.

    By the end of the month, the Los Angeles Department of Water&Power is expected to flip the switch on the home's 24-kilowatt installation of thin-film solar panels, bringing to life what is believed to be the largest residential installation of its kind in the country.

    The thin-film panels generate about 50 percent less electricity per square foot and cost about 10 percent more than traditional photovoltaic panels, but the flexible film can handle curved surfaces and integrate less obtrusively into a home's silhouette. It's also lighter weight - an advantage in earthquake country - and unlike bulky bracketed panels, thin-film doesn't need to be drilled into the roof, reducing the risk of leaks.

    Harberger's installation will power not only his lighting, electronics and air conditioning, but also systems that would traditionally be juiced with natural gas. The thin film will heat all the water for the home and run the forced-air heating system as well as the clothes dryer and oven.

    "There are so many advantages to going all electric with very little natural gas," Harberger said.

    Outside, natural gas powers a barbecue grill and an auxiliary heater for a shallow pool that is otherwise warmed by the sun or an electric heater. Inside, natural gas is used only for the kitchen cook top and a living room fireplace.

    Less natural gas indoors means fewer vents to shuttle carbon monoxide outside, resulting in a less cluttered exterior.

    Harberger, 49, designed the house, which sits on a quiet street frequented by trotting horses. He has been living in it for two years with his wife, two children and three dogs while planning the solar installation, which cost $160,000 before a DWP rebate of about $50,000. A federal tax credit will be about $30,000. The panels are made by Uni-Solar, based in Auburn Hills, Mich., and were installed by ADR Solar Solutions, a Woodland Hills, Calif., firm that specializes in thin-film solar.

    Like most homeowners who go solar, Harberger considered the bulkier panels that are commonplace across the country. But the metal-sheet construction and curvature of his roof led him to Uni-Solar thin film.

    Mounted on the southern- and western-facing sections of the roof, the thin film can better handle seasonal differences in the sun's patterns and maximize electricity generation. The uppermost portion of the panels will perform better in the summer; the lowermost panels will do better in the winter.

    "Right now, our electricity use is balanced," Harberger said, adding that his family will use as much electricity as it generates, on one condition. "If I can control my kids," he said. "I tell them to watch the smallest TV possible."
    (c)2011 the Los Angeles Times
    Distributed by MCT Information Services

    Why Solar Power?

    Solar power is the future of energy it produces no pollution and generates energy from natural source that is not reduced by its  energy consumption
    • Solar power is becoming a more common energy source and according to the American Solar Energy Society, as it is growing worldwide at 40-50% annually.
    • On average families are able to decrease their energy bills by 75 percent 
    • Significantly reduces pollution
    • Increases your property value   


    GreenerZA is working hard to help provide alternative energy to  reduce the amount of pollution