The U.S. Department of Energy aims to make electricity from the sun cheaper than that from burning coal or natural gas.
NATIONAL HARBOR, Md.—Silicon translates sunshine into electricity—and Earth receives enough sunshine in a daylight hour to supply all of humanity’s energy needs for a year. But despite being as common as sand, photovoltaic panels made from silicon—or any of a host of other semiconducting materials—are not cheap, especially when compared with the cost of electricity produced by burning coal or natural gas. The U.S. Department of Energy (DoE) aims to change that by bringing down the cost of solar electricity via a new program dubbed “SunShot,” an homage to President John Kennedy’s “moon shot” pledge in 1961.

The U.S. Department of Energy aims to make electricity from the sun as cheap as that from burning coal or natural gas – by 2017.
Image: Dennis Schroeder, NREL Staff Photographer.

“If you can get solar electricity down at [$1 per watt], and it scales without subsidies, gosh, I think that’s pretty good for the climate,” notes Arun Majumdar, director of the Advanced Research Projects Agency–Energy (ARPA–e), the DoE’s high-risk research effort. “With SunShot, the goal is to reduce the cost of solar to [$1 per watt] in the next six years.”

As it stands, melting silicon or depositing thin layers of copper indium gallium selenide, then manufacturing photovoltaic modules and installing them on rooftops or in large arrays in the desert, can cost as much as $10 per watt. And whereas some technologies can deliver modules for roughly $1 per watt, installation at least doubles that.

“We are making solar for the masses…to get to [a] cost point that is viable,” said Bruce Sohn, president of Columbus, Ohio–based First Solar, the world’s largest thin-film photovoltaic manufacturer, which claims it can produce its modules for less than $1 per watt, on a panel at ARPA–e’s second annual summit on March 1. “We are looking to make something that can compete head to head with fossil fuels over the long term.”

As part of the new SunShot initiative, DoE committed some $27 million to fund novel methods for producing solar cells and their components—like 1366 Technology’s effort to grow pure silicon wafers directly rather than hewing them from long ingots of the material or Solexant’s effort to build thin-film solar cells from semiconducting materials that are neither toxic nor rare. The goal is to produce solar modules at roughly 50 cents per watt with attendant hardware and installation costing the same amount. To reach that target the photovoltaic cells will have to convert at least 20 percent of the sunlight that shines on it into electricity and cost only 25 cents per watt by 2017. “The future of the U.S. depends on three securities: national, economic and environmental. The foundation of all of this is innovations in energy technology,” Majumdar said in his own speech to the summit. “The future is still up for grabs. How do we win the future? Invent affordable clean technology. Make them locally, sell them globally.”

Of course, harvesting the sun’s power is not limited to photovoltaic panels. The DoE push also will incorporate efforts to create solar-thermal power plants that can store the heat of the sun for 12 to 17 hours by 2020, along with attempting to address some of the issues surrounding permitting, inspection and connection of solar systems to the electricity grid. “We want change, we want innovation, we want to overthrow the old energy order,” said former California governor Arnold Schwarzenegger in a summit keynote address. “We want a new era of energy and a new era of American competitiveness.”

Former California Governor Arnold Schwarzenegger addresses the 2011 APRA-E Technology and Innovation Summit on California’s role in clean energy.

Already, electricity from the sun costs roughly the same as that generated from burning fossil fuels in places like Hawaii, which remains the only state to rely on imported oil for the bulk of its power. And solar power represents the fastest-growing sector of electricity generation. U.S. solar production in 2010 increased by nearly one gigawatt (billion watts), although that represents roughly the amount of electricity one nuclear power plant can produce. But even at that pace of adoption—spurred by both federal and state government largesse—solar still produces less than 1 percent of all U.S. electricity. And in 2035, by which time the DoE’s Energy Information Administration (EIA) predicts that solar will have grown fastest among all energy resources (increasing sevenfold), all renewables put together, solar included, will only provide 14 percent of U.S. electricity.

The EIA has often been wrong in such long-term forecasts, but competing with natural gas—newly cheap thanks to the vast resources tapped by fracking in the eastern U.S.’s Marcellus Shale Formation—may prove difficult, even with SunShot. “Natural gas has low capital cost, higher fuel cost but overall lowest costs,” noted EIA Administrator Richard Newell at the ARPA–e conference. “There are significantly higher costs for other power sources.”

Yet, even at a higher price, solar can offer benefits, which is why Duke Energy has invested $50 million putting solar arrays on the roofs of grocery stores and some of its other large customers. “Distributed solar can be thought of as a distributed resource, a multiple value resource,” Duke Chief Technology Officer David Mohler told ARPA–e attendees. “The proper comparison for that is not the cost of a bulk power system, it’s the cost and benefit of having an embedded resource.”

And flexible solar cells in sheets have already found novel applications powering the telecommunications and other electronic equipment of U.S. Marine units deployed in Afghanistan. Small-scale solar is also booming in places such as Kenya that do not have an electricity grid for charging cell phones or batteries that power lights at night. “We will need every energy resource we can lay our hands on,” said Kurt Yeager, executive director of the Galvin Electricity Initiative, an effort to develop the smart grid in the U.S. “There are two billion people in the world without access to electricity. Security means giving them energy.”

Of course, the DoE has already invested some $1 billion in solar energy research since the turn of the century, funding efforts to develop “black” silicon or cells employing quantum dots. “If renewables are cost-competitive with fossil fuels then it’s a very, very different world,” Secretary of Energy Steven Chu said at the ARPA–e summit.

Secretary for the US Department of Energy, Steven Chu, discusses the big picture of how the United States uses Energy and why innovation in clean technology is the key to Winning the Future.

Yet, despite inventing the technology in the 1950s and more than 30 years of government support, the U.S. share of the global market for photovoltaic modules is down from more than 40 percent in 1995 to just 6 percent in 2011. China’s Jiangsu Province alone—home to Suntech Power, the world’s largest maker of photovoltaic panels—has begun investing more than $152 million a year in solar technology since 2009.

“Just because we lost the lead doesn’t mean we can’t get it back,” Chu said. “We still have the opportunity to lead the world in clean energy…but time is running out.”

Article by By David Biello.
Source: scientificamerican.com.

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.

Eco Factor: Concept lighting system powered by solar energy.

© Image by www.behance.net.

Solar energy and other renewable forms of energy generating systems not only do their bit for the environment but also keep the user close to the environment. Sinthesya is a concept solar-powered lamp designed for indoor and outdoor use that is inspired from the natural process of photosynthesis. The lamp generates energy from the sun during daytime and its high-intensity LEDs provide illumination as night falls.

© Image by www.behance.net.

The lamp with a movable head ensures that the user can focus the illumination at a particular area like a book or your favorite wall painting. With waterproof credentials, the lamp can be placed in your garden for charging without worrying about unseasonal rainfall. An energy meter shows the amount of charge present in its batteries allowing the user the charge it only when needed.

© Image by www.behance.net.

The Dark Side:

The designer doesn’t state the materials with which the lighting system will be built. If it’s plastic then it might just use more energy in its construction that it will actually save during its lifetime.

© Image by www.behance.net.

See more HERE.

Team Germany was the winner in the U.S. Department of Energy’s Solar Decathlon, which had 20 entries in a contest to create the best solar-powered house.

© Inhabitat.

20 homes soak up the sun’s rays on Washington DCs National Mall. They need all the energy
they can get, to power everything from ventilation systems to home entertainment centers.
Its required in the recent Solar Decathlon, sponsored by the U.S. Department of Energy.

SOUNDBITE: (English) Richard King, U.S. Department of Energy: “The solar decathlon is a
competition for university schools of architecture and engineering to design from the ground
up a solar powered, high efficiency, self-sustaining house.”

Over several days, student teams are judged across 10 events, from design, to whether
the house would sell on the market.

The winning house was created by Team Germany.
The Team Germany home is covered in thin solar panels, giving the house a shiny, black
appearance – with a twist.

SOUNDBITE: (English) Sardika Meyer, Team Germany: “We have photovoltaic panels across all
sides of the house. And in between as a second design element we have colorful acrylic glass
pieces to kind of open the house up. We lovingly call them sun freckles.”

The design-to-construction process takes two years. This is the fourth solar decathlon,
and the next one will be held in 2011. The event draws around 100,000 visitors to the
National Mall, where students show off their designs while making the pitch for energy efficient
technologies like solar and using recycled goods for building material. All 20 homes will live on.
Some are headed back to university campuses for housing and research. Others will be donated
for use by various organizations. And two are for sale.

Read more here.
See a video here.

A group of German firms has collaborated to launch what is to be the largest solar energy
project of its kind. The project, termed Desertec, aims to construct several solar thermal electric
power plants throughout North Africa and parts of the Middle East. Ultimately, the project will
supply electricity to European households using energy generated from the Sahara.

Electricity will be generated in power plants using parabolic mirrors, which creates enough heat
to produce the steam needed to drive turbines and electricity generators. High voltage lines will
carry electricity to Europe, supplying 15 percent of the continent’s electricity requirements.

Other parts of the world using this method of electricity generation span from the Mojave Desert
in California to the Andalusia region in the south of Spain.

© Inhabitat.
Solar parabola in action: The Desertec project could provide up to 20 percent of Europe’s energy needs by 2050.

Read more on this subject on www.germany.info