Here’s an easy way to learn the way solar panels work.

What is solar power?

Solar energy is radiant energy that is produced by the sun. Daily the sun radiates, or sends out, a huge amount of energy. The sun radiates more energy in a single second than people have used since the beginning of time!

The energy of the sun derives from within the sun itself.

Like other stars, the sun is a big ball of gases––mostly hydrogen and helium atoms. The hydrogen atoms in the sun’s core combine to create helium and generate energy in a process called nuclear fusion.

During nuclear fusion, the sun’s 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. However 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 countless years for the energy in the sun’s core to make its way to the solar surface, and somewhat 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.

Simply a small percentage of the power radiated by the sun into space strikes our planet, one part in two billion. Yet this volume of energy is enormous. Each day enough energy strikes the United States to supply the nation’s energy needs for one and a half years!

Where does all this energy go?

About 15 percent of the sun’s energy that hits our planet is reflected back into space. Another 30 percent is used to evaporate water, which, when lifted into the atmosphere, produces rainfall. Solar power also is absorbed by plants, the land and the oceans. The remaining could be employed to supply our energy needs.

Who invented solar energy?

Humans have harnessed solar power for hundreds of years. 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 a century ago in France, a scientist used heat from a solar collector to make steam to drive a steam engine.

At the beginning of the 20th century, scientists and engineers began researching ways to use solar energy in earnest. One important development was a remarkably efficient solar boiler introduced by Charles Greeley Abbott, a United States astrophysicist, in 1936. The solar hot water heater became popular at this time in Florida, California, and the Southwest. The industry started in the early 1920s and was in full swing right before World War II. This growth lasted up to the mid-1950s when low-cost gas had become the primary fuel for heating American homes.

People and world governments remained largely indifferent to the possibilities of solar power until the oil shortages of the 1970s. Today, people use solar energy to heat buildings and water and to generate electricity.

How we use solar power today?

Solar power is employed in a variety of ways, of course. There are two very basic types of solar energy:

* Solar thermal energy collects the sun’s warmth through one of two means: in water or in an anti-freeze (glycol) mixture.

* Solar photovoltaic energy converts the sun’s radiation to usable electricity.

Listed below are the five most practical and popular solutions on how solar energy is employed:

1. Small portable solar photovoltaic systems. We see these used everywhere, from calculators to solar garden products. Portable units may be used for everything from RV appliances while single panel systems are used for traffic signs and remote monitoring stations.

2. Solar pool heating. Running water in direct circulation systems via a solar collector is a very practical solution to heat water for your pool or hot tub.

3. Thermal glycol energy to heat water. In this method (indirect circulation), glycol is heated by sunshine and the heat is then transferred to water in a hot water tank. This technique of collecting the sun’s energy is much more practical now than in the past. In areas as far north as Edmonton, Alberta, solar thermal methods to heat water are economically sound. It can pay for itself in three years or less.

4. Integrating solar photovoltaic energy into your home or office. In many parts of the planet, solar photovoltaics are an economically feasible approach to supplement the power of your own home. In Japan, photovoltaics are competitive with other types of power. In the USA, new incentive programs make this form of solar power ever more viable in many states. An increasingly popular and practical way of integrating solar energy into the power of your home or business is through the use of building integrated solar photovoltaics.

5. Large independent photovoltaic systems. When you have enough sun power at your site, you may be able to go off grid. You may also integrate or hybridize your solar power system with wind power or other forms of renewable energy to stay ‘off the grid’.

How do Photovoltaic panels work?

Silicon is mounted beneath non-reflective glass to produce photovoltaic panels. These panels collect photons from the sun, converting them into DC electric power. The energy created then flows into an inverter. The inverter transforms the energy into basic voltage and AC electrical power.

Solar cells are prepared with particular materials called semiconductors like silicon, which is presently the most generally used. When light hits the photovoltaic cell, a particular share of it is absorbed inside the semiconductor material. This means that the energy of the absorbed light is given to the semiconductor.

The energy unfastens the electrons, permitting them to run freely. Solar power cells also have more than one electric field that act to compel electrons unfastened by light absorption to flow in a specific direction. This flow of electrons is a current, and by introducing metal links on the top and bottom of the Photovoltaic cell, the current can be drawn to use it externally.

Do you know the positives and negatives of solar technology?

Solar Pro Arguments

- Heating our homes with oil or natural gas or using electricity from power plants running with fossil fuels is a reason behind climate change and climate disruption. Solar power, on the other hand, is clean and environmentally-friendly.

- Solar hot-water heaters require little maintenance, and their initial investment may be recovered within a relatively small amount of time.

- Solar hot-water heaters can work in almost any climate, even in very cold ones. You just have to choose the best system for your climate: drainback, thermosyphon, batch-ICS, etc.

- Maintenance costs of solar powered systems are minimal and the warranties large.

- Financial incentives (USA, Canada, European states…) can aid in eliminating the price of the initial investment in solar technologies. The U.S. government, as an example, offers tax credits for solar systems certified by by the SRCC (Solar Rating and Certification Corporation), which amount to 30 percent of the investment (2009-2016 period).

Solar Cons Arguments

- The initial investment in Solar Water heaters or in Solar PV Electric Systems is higher than that required by conventional electric and gas heater systems.

- The payback period of solar PV-electric systems is long, as well as those of solar space heating or solar cooling (only the solar domestic hot water heating payback is short or relatively short).

- Solar water heating does not support a direct conjunction with radiators (including baseboard ones).

- Some air-con (solar space heating and the solar cooling) systems are very pricey, and rather untested technologies: until recently, solar air-con has not been an economical option.

- The efficiency of solar powered systems is determined by sunlight resources. It is in colder climates, where heating or electricity needs are higher, that the efficiency is smaller.

Article by Barbara Young.

Barbara Young writes on motorhome solar panels; in her personal hobby site 12voltsolarpanels.net. Her work is devoted to helping people save energy using solar energy to reduce CO2 emissions and energy dependency.

Everyone is familiar with the practical everyday use of renewable solar energy in a form of solar panels on roofs, solar garden lights and various solar gadgets.
Did you know that for many years now scientists around the globe have been working on a concept of implementation Solar Sail technology for space exploration?
The future is here!

Image from Japan Aerospace Exploration Agency (JAXA).

If everything goes well, a new Japanese weather probe and its solar sail are scheduled to take off on May 21 2010 for a six-month journey to study Venus.
The launch requires a specific time window each day in order to accomplish a successful course toward Venus.
Watch this event broadcast live HERE.

World’s first interplanetary solar sail spacecraft IKAROS, sail spreading CG image.
Read more about Japanese solar sail concept testing here.

1,100-pound Akatsuki spacecraft, which means “Dawn” in Japanese, won’t take off unaccompanied. Along comes a solar sail named Ikaros (700-pound Interplanetary Kite-craft Accelerated by Radiation Of the Sun) as one of five smaller secondary payloads. The four remaining payloads represent small Earth satellites and experiments constructed by private universities and corporations.

Solar sails (also called light sails or photon sails) are a form of spacecraft driving force using the radiation pressure of light from a star or laser to push enormous ultra-thin mirrors to high speeds.
Theoretically solar sail crafts can reach speeds of 20% speed of light, if given enough size and area.
NASA has successfully tested deployment technologies on small scale sails in vacuum chambers.
No solar sails have been successfully used in space as primary propulsion systems before, research in the area is continuing. It is noteworthy that both the Mariner 10 mission, which flew by the planets Mercury and Venus, and the MESSENGER mission to Mercury demonstrated use of solar pressure as a method of attitude control, in order to conserve attitude-control propellant.

Solar Pressure-Powered Sails. NASA “Destination Tomorrow” Segment explaining how solar pressure-powered sails may be used to propel spacecraft deep into space.

Image by RAFAA Architecture & Design.

This solar energy generating tower is going to be located on the coast of Rio de Janeiro. It is one of the first buildings that are being designed for the 2016 Rio Olympics. This solar energy generating tower looks like an enormous waterfall. The Solar City Tower is designed by Swiss (Zurich-based) company – RAFAA Architecture & Design. It features a large solar system to generate energy during the day and a pumped water storage system to generate energy at night. RAFAA’s goal is that a symbolic tower such as this can serve as a starting point for a global green movement and help make the 2016 Olympic Games more sustainable.

Image by RAFAA Architecture & Design.

The Solar City Tower is a solar power plant. It is designed to create renewable energy for use in the Olympic Village as well as the city of Rio. A large solar power plant generates energy during the day. Any excess power not used during the day is utilized to pump seawater into a storage tank within the tower. At night, the water is released to power turbines, which will provide nighttime power for the city. A special feature of the building is the urban waterfall. Water is pumped out to create a waterfall over the edges of the building, which Rafael Schmidt of RAFAA says will be “a symbol for the forces of nature.”

Image by RAFAA Architecture & Design.

Access to the eco tower is gained through an urban plaza and amphitheater 60 meters above sea level, which can be used for public gatherings. On the ocean side of the 105 meter tower (behind the waterfall) is a cafeteria and shop. An elevator takes visitors up to the top floor where an observation deck offers 360 spectacular views of the ocean and Rio. At level 90.5, there is a retractable bungee platform for daring guests. Let the games begin!

View at the tower from the coast of Rio de Janeiro.
Image by RAFAA Architecture & Design.

A solar-charged light might seem like just another green gadget to the average American, but for families in rural Africa, it could prove revolutionary.

One or two Solar Pebbles can provide enough light for one home, as houses in rural Africa are generally small.
Image from timo-aim.com.

Product design consultancy Plus Minus Design is trying to replace unsustainable and potentially dangerous lanterns in the homes of off-grid Africans with the Solar Pebble. Engineered with the economic constraints of developing-world citizens in mind, the Solar Pebble will provide one hour of LED light for every two hours of charge, and will cost only $2.70 to manufacture.

A fully charged Solar Pebble can provide up to 22.5 hours of LED light.
Image by Plus Minus Design.

Plus Minus Design, based in Leeds, U.K., was founded by three undergraduate students at the University of Leeds. While studying product design and engineering, Adam Robinson, Henry James, and Tom Eales were given the opportunity to work with SolarAid, a charity in the U.K.

SolarAid, which works to fight poverty and climate change, worked with the students to develop a solar-powered alternative to kerosene lanterns. Those lanterns, commonly used in rural Africa, draw 20 percent of an average Malawian family’s income, SolarAid said, and pose respiratory health problems, as well as create fire hazards.

Image from i.pbase.com.

The undergrads spent months researching life in Malawi to design a product that addressed the needs of rural families, but also took environmental, economic, and lifestyle factors into consideration. Local maintenance, potential for the development of children’s education, and adaptability to charge other devices were the team’s key requirements.

Though mobile phones and portable radios are common in rural Africa, individuals must travel to locations with mains power for charging. With this issue in mind, the engineers designed the Solar Pebble to charge phones and portable devices in addition to providing light.

Plus Minus Design was also able to address the need for local maintenance with a simply designed product assembled through snap-in parts and repairable with basic tools.

The Solar Pebble provides light and a means of portable charging, but its implications are even greater. The lamp will ship partially assembled, providing jobs for locals who would finish assembly. Furthermore, Plus Minus Design hopes the lamp will increase radio usage, providing rural African families with HIV/AIDS prevention information.

According to Robinson, the Solar Pebble will launch in Uganda and the U.K. by midsummer.

Article by Sharon Vaknin.
Read more at Green Tech.

In an area of Ngatimoti, four neighbours who share green values in their lifestyles are about to open their properties to the public.

Labor of love: The Laufkotters’ home in Ngatimoti was constructed from 80 percent straw and 20 percent clay over a two-year period.

Sixteen years ago, Peter and Mechthild Laufkotter decided their seaside Motueka home was limiting their self-sufficiency, so they made a move that many people dream of.

The couple now live on a 25-hectare block in tranquil Ngatimoti, 20 kilometres from Motueka, with a charming light earth house that overlooks vegetable gardens, fruit trees and surrounding bush and forest.

There they take pleasure in the delights of eating home-grown produce, preserving it for storage in their cellar and for use throughout the year. On their path to greater self-sufficiency they’ve learned many new skills, and enjoy being independent.

“If you live in harmony with the land, it’s something that is deeply satisfying. You put your energy into all the food that you eat. It has a different value than just the nutrition,” says Mrs Laufkotter, a trained dietician who now works as a teacher aide at Ngatimoti School and as a yoga teacher.

The Laufkotters’ property is one of four organic Ngatimoti properties that will feature in the Green Lifestyles tour on Sunday, March 14.

Organised by the Motueka branch of the Green Party, its aim is to show how simple green concepts have been applied to create beautiful homes, gardens and lifestyles for the four host families, and how an eco-friendly life works for those looking for inspiration.

Motueka Greens treasurer Heather Spence says as well as the Laufkotter’s property, the tour will go to a commercial organic plum and apple orchard, a home-based flax-growing and craft business, and a home that features an outdoor bathroom and woodlots.

She says people on the tour – the first of its type held by Motueka Greens in part as a fund-raising event – will be able to talk to the hosts about such things as sustainable house design, different building materials and techniques, and how to achieve things like productive organic gardens, solar power, composting toilets and smart water use.

The tour is structured so people walk a 3km route in groups from one property to the next through fields, woodlots, orchards and gardens.

The Laufkotters, who have three grown sons, moved to the region from Germany in 1981 and lived for 14 years by the sea in Motueka. When they bought their Ngatimoti property about 16 years ago, they bought it with a friend to reduce the mortgage, but later bought his share.

The couple opted for a three-bedroom light earth house, which is of timber construction with walls made from a mixture of 80 percent straw and 20 percent clay. Lighter than mud-brick homes, the house, which is built on a hillside, also has great insulation, says Mr Laufkotter, who works from home as a sign writer.

They built the house over two years, and in a further bid to save money “and not end up with a huge mortgage”, they collected windows, doors and other features for the house during the years in advance of building. They managed to secure a whole house lot from Christchurch, with other parts coming from Nelson.

“We designed the house around what we had,” Mrs Laufkotter says.

The home features solar water heating and a composting toilet, which separates solids from liquids. The liquid gets fed to the citrus trees, which, like the nitrogen it contains, and the solids, are also spread around fruit trees.

They said they wanted a composting toilet because they don’t have a huge supply of water on the land.

“With every flush [from a conventional toilet], we might not have much to drink by the end of February,” Mr Laufkotter laughs. Over the years, they’ve established large organic vegetable gardens fed with lots of rich compost and organic manure, fruit and nut orchards and a 50-tree olive grove, and have regenerated bare paddocks by planting hundreds of native trees. They also keep some chickens and 14 Scottish highland cattle.

The cattle are kept mainly to control the pest plant old man’s beard on the property, but the Laufkotters also occasionally kill them for food to keep the numbers manageable. As the Laufkotters are not big meat eaters, one animal supplies them with meat for a year.

Their increasing self-sufficiency means they’re always trying new things and learning new skills. Mr Laufkotter learned butchering and makes his own salami and dried meats, which are stored in the cellar along with homemade juices, wines, beer and other preserves.

Hops that Mr Laufkotter found growing wild in the Graham Valley line the entrance to the cellar, which provides a cool sanctuary in the heat of summer.

“Every season is different and there’s always new things to be learned,” he says.

“Coming from Germany, chutneys didn’t exist. We have learned that [how to make them]. We make them here and never have to buy them,” Mrs Laufkotter says.

“We’ve got everything we need here and we never go hungry at all,” Mr Laufkotter adds.

“I don’t have to spend eight hours in my workshop. I don’t have to chase the jobs.”

He also makes his own bread, which led him to last year grow a 20-square-meter patch of barley for a trial, because he wanted to know how to grow grains. The birds loved the experiment.

“I made about 2kg out of 20sqm. If I wanted to support my bread making with my own grain, I’d have to grow a paddock of it.”

Mrs Laufkotter, who makes her own herb teas, says being as self-sufficient as possible takes effort.

“People will come here and say `this is beautiful’, but wouldn’t really have a clue about what it means to sustain something like that.

“I try to be in the garden every day for at least an hour. There are some days on the weekends I would spend the whole day [outside on the property].

“Most evenings in summer, I’d be in the garden until it’s dark.

“When you’ve got a lot like this, that creates a huge workload, but if you know it’s for yourself, you don’t mind.”

One of the nicest aspects of where they live is that their neighbors share their green philosophy, they say.

In fact, once a year, the neighbors get together to maintain White Rock, a special area of quartz at the top of the Laufkotters’ property.

“The best thing about it is you never have an argument about things like spraying,” Mr Laufkotter says.

“They’re all on the same wavelength.”

Source: stuff.co.nz