About Solar Power

solariconaboutIt’s no secret that sunlight is the world’s largest energy resource, and humans have spent centuries harnessing the sun’s power in the form of solar energy. In recent years, the availability and popularity of solar technology has increased both in the U.S. and around the globe due to decreasing costs. The demand for skilled solar technicians is also rising quickly due to ongoing developments in solar power, including: photovoltaics (solar cells), solar water heating, solar process heating/cooling, passive solar design, and concentrating solar power. Photovoltaics (PV) are utilized in Iowa during the summer months when solar power can offset the demand for electricity needed to run air conditioners.


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About Solar Energy

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solar"Solar is the Latin word for sun—a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the sun falls on the earth in one hour than is used by everyone in the world in one year. A variety of technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for homes and businesses are solar water heating, passive solar design for space heating and cooling, and solar photovoltaics for electricity.

"Businesses and industry also use these technologies to diversify their energy sources, improve efficiency, and save money. Solar photovoltaic and concentrating solar power technologies are also being used by developers and utilities to produce electricity on a massive scale to power cities and small town."  (From NREL introduction to Solar Energy Basics.  Image left: NREL )

For information about preparing for a Solar Energy
career, use the links at the right. 

About Iowa and Solar Power

Despite solar power's "clean" reputation, this technology has not yet become a popular renewable energy choice for Iowa homes and businesses.  As "Iowa Source Magazine" author writes: ". . . for the last 10 years my neighbors and I have had 100 percent of our electric power delivered abundantly by solar energy. And don’t forget that all of nature has been operating exclusively on solar energy for billions of years. Nature’s systems that clean our air and water, maintain the fertility of the land, moderate the climate, and create the complex web of life on earth require thousands of times the energy used by man, yet operate exclusively on solar energy." (See Resources below.)

powerfilm-solartent-militaryDepartment of Transportation. An ISU renewable energy newsletter from a decade ago states that Iowa’s Department of Transportation uses photovoltaic power to charge the batteries on many of its traffic control signs and explains that traditional power sources are difficult to use for many of the signs' locations. The DOT's large message panels, which stretch across lanes of interstate highways to warn motorists about hazards, also are powered by photovoltaic cells.

PowerFilm Solar Inc. In 1988, this Ames company was founded to continue researching ISU's "thin film" solar technology and to design and manufacture thin film commodities. 

Among PowerFilm Solar's developments are Powershades, which are tents with thin film solar technology on canvas. The U.S. military has been trying these shades in Afghanistan (photo right, sheltering a tent). The model pictured can hold two kilowatts of power. The company's website states the company also provides the military with foldable solar chargers that can charge laptops, cell phones and GPS units. “We supplied the military with an initial quantity for them to try out, and it’s gaining popularity. The Ames company has also provided their products to disaster relief organizations; for example, in Haiti. “Alternative energy sources are really going to shine in mission scenarios where you don’t want to use a generator because you don’t want the noise or heat signature that goes along with it, or where re-supplying that generator with fuel doesn’t make sense,” said a senior engineer at the Natick Soldier Research Design and Engineering Center.  http://www.powerfilmsolar.com


wiki_Solar_ImpulseEnvision the Future!· Swiss "Solar Impulse" Airplane

  In May 2011, a member of Switzerland's Solar Impulse aeronautical team flew on solar energy alone in the light and then in the dark for over 12 hours (http://www.solarimpulse.com/). While solar air transportation is not likely to replace commercial transportation, the Swiss team is succeeding in its dreams of long distance flight; the team also wants to succeed in raising world awareness about our need for renewable energy technologies.  In the following quote, Yann-Aruthus Bertrand, a a French photographer, journalist, reporter, environmentalist, and producer of "Home" (http://www.youtube.com/homeproject#p/a/f/0/jqxENMKaeCU) makes the connection between Solar Impulse and our planet: "It is a question of a symbol, as we will probably never carry 300 passengers in a solar airplane, but it is a symbol that affects all of us. In fact, aren't we all on Earth in the same situation as the Solar Impulse pilot? If he does not have the right technologies or wastes his energy, he will have to land before the rising sun enables him to continue his flight. And we, if we do not invest in the scientific means to develop new energy sources, we shall find ourselves in a major crisis, which will prevent us from handing over the planet to the next generation." 

The team is planning a future Solar Impulse round-the-world trip. (http://www.solarimpulse.com/blog/2011/05/12/all-lights-at-green/)  By the way, this is not the first solar plane!  See DOE's "History of Solar Cells" (http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf) regarding solar flights in 1981, 1996, 1998, and 2002.   

About Solar and You

  Solar heat and light: these are energy from the beginning of time!· A U.S. Department of Energy link to their "History of Solar Cells" document takes a reader back to a 7th Century B.C solar "technology"a simple magnifying glass that concentrated the sun's rays to burn wood, and mysteriously, ants!  Jumping through the centuries to 1954, a U.S. company, Bell Labs, announced the invention of the first modern silicon solar cell; Bell Labs states their invention had only 6% efficiency. Responding to that innovation, a 1954 New York Times article  informed readers that solar cells would eventually connect us with the  "limitless energy of the sun." (http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf)    

The "History of Solar Cells" further reveals that solar development in the U.S. advanced steadily but slowly for about a hundred years.  Most progress has been related to NASA space program work.  But in March 2011 the Solar Energy Industries Association (SEIA) reported the following: “. . .U.S. solar energy industry had a banner year in 2010 with the industry’s total market value growing 67 percent from $3.6 billion in 2009 to $6.0 billion in 2010. . . Every day, Americans across the country are going to work at well-paying, stable jobs at solar companies, from small installers all the way up to Fortune 500 companies,” said Rhone Resch, SEIA president and CEO." (http://www.seia.org)

Let's put you in the picture!

  • Electric vehicles (EV) are here today and may be personally in your future .  Some 2011 options are the Tesla Roadster 2.5 with an estimated 119 MPGe (Ge = gallon equivalent), the Nissan LEAF's 99 MPGe and the Chevy Volt's 93 MPGe.  (http://www.treehugger.com/files/2011/05/tesla-roadster-electric-car-rated-111-mpge-us-epa.php)
    How about a golf cart instead?  Check out Iowa's Powerfilm Solar top at http://www.powerfilmsolar.com/solargolftops/. Watch the news for hybrids, such as the new Prius Level 3 model.
  • Of course,  that future EV will need a charging station.  An enterprising web designer has already set up a website for finding solar charging stations in the U.S: CarStations.com.   The site shows that as of May 2011, Iowa has nine charging stations, with four of them being in the entrepreneurial small town of Elk Horn, which is only a few miles north of I-80.  The University of Iowa's solar-powered EV charging station for campus Facilities Management vehicles is available as of summer 2011. (http://facilities.uiowa.edu/uem/renewable-energy/solar-energy.html)  In the future, keep in mind that solar charged stations like this UI example is preferable to electric grid-based charging whenever possible. For an explanation of charging technology and levels as well as charge-times, see http://electriccarchargerssandiego.com/EV-Charging-FAQs.html  
  • You might someday want a solar home: a passive solar design relies on orientation of windows toward the sun, and an active solar design uses solar cell arrays on the roof or ground to collect and distribute energy.  Passive solar design is defined at http://www.energysavers.gov/your_home/designing_remodeling/index.cfm/mytopic=10260, and active solar systems are defined at http://www.energysavers.gov/your_home/space_heating_cooling/index.cfm/mytopic=12490
    The Hodges passive solar home in Ames, Iowa, was designed and built in 1978-1979.  See http://www.public.iastate.edu/~lhodges/house.htm for photos and the story.
    Solar homes and everything on the property may be planned to be entirely off-grid, meaning independence from powerlines and the power company.  On the other hand, the home can  be grid-connected, with an electrical meter connected to powerlines and the power company.  If you use less or none of the power company's energy, you pay less or nothing.  If your system creates extra energy not needed in your home, then the meter can literally run backward, which means the power company may use the energy you created.  The company can credit your account with energy (but not usually with a monetary reimbursement).  In any of these solar design scenarios, you may decide to back up your own power needs with battery storage. 
  • Interested in using solar? Iowa's solar exposure is good.  For example, Germany, the world’s second largest user of solar-generated electricity, is located betwwn 48 to 54 degrees latitude; that is farther north than Iowa's approximate 40 to 43 degrees latitude.  Cloudy and cold places in the U.S. like Maine and the Pacific Northwest have lots of solar-heated and -powered buildings.  Like those locales, Iowa also has solar resources. http://www.iowasource.com/home_garden/solarmyths_0704.html  The NREL map below indicates Iowa's annual average daily total solar resource; i.e. 4.5 to 5 hours.
    Source of map below: National Renewable Energy Laboratory (NREL), "PV Solar Radiation (Flat Plate, Facing South, Latitude Tilt)-Static Maps." From Dynamic Maps, GIS data, and Analysis Tools, accessed 5 March 2009. Note: The map shows annual average daily total solar resources. The insolation values represent the resource available to a photovoltaic panel oriented and tilted to maximize capture of solar energy. This map displays an annual average; maps for individual months reflect the seasonal variation associated with solar energy.


Additional Resources

Teach a Kid About Solar Energy