Débat problématique énergétique / effet de serre / climat, etc.
Energie photovoltaïque

Solar Power is Hot -- Too Hot; You can look but you can't buy.
August 09, 2005 By Betsey Bruner, The Arizona Daily Sun
    That was the word Friday from the solar energy corner of the Southwest Sustainability Expo at NAU. A worldwide shortage of solar panels has put most local projects on hold.
    "I get them in and they are sold before I get them in the warehouse," said Ursula Garrett, owner of ETA Engineering in Tempe. "We're back-ordered. The demand increased and the silicon suppliers aren't keeping up."
    Garrett said the 200 Sharp 165-watt solar panels in her warehouse are all sold, and more won't be in until the end of the month.
    The New York Times reported on the phenomenon Friday, even quoting a buyer in Illinois as finally finding some panels at Northern Arizona Wind & Sun in Flagstaff.
    But at the company's booth in the NAU Fieldhouse, electrician David Lauzon said supplies were tight and the price was going up.
    "They're shipping them to Germany," Lauzon said. "Germany's just going real big on solar. I hear they make four times what they make if they sell them over there."
    A 120-watt Kyocera photovoltaic module (solar panel) from Japan that was about $400 several years ago now sells on sale for about $550, if you can find one, he added.
    Other reasons for the backlog of orders include the recent passage in California and other states of generous tax credits for solar energy installation by homeowners.
    Wind turbines, however, are not as scarce.
    "Compared to solar, wind per watt is cheaper than solar, but, of course, you have to have wind and you have to get it above the pines," said John Ervin, another Wind & Sun salesman.
    Ervin said areas outside of Flagstaff, such as Williams, Winslow, Doney Park and toward the reservation, have pretty good wind resources.
    At a nearby booth, Mason Rumney III waxes poetic about his personal passion: earth-friendly masonry domes. He has lived in one for about 17 years in Sedona, near the Palatki ruins.
His home is solar and wind powered. It also has passive energy systems that use available natural conditions such as sunlight and wind to warm or cool the living environment.
    "This is the ultimate passive design," he said. "You don't need air conditioning, even here in Arizona. If they would build this way, they wouldn't need the air conditioning that's 50 percent of the energy consumption in his country."
    A shot-crete dome like his is made by spraying a concrete foam material over a giant inflated balloon. It is quick to build and relatively inexpensive and can be made in three days for about $30 per foot.
    "It's like a pool, only upside down," he explained. "The fourth little piggy would have lived in a masonry dome. A dome uses a third less materials. These particular domes can save from 60 to 80 percent on your cooling and heating bills."
    The New Frontiers' booth is offering free samples of organic food to illustrate the sustainable production of food. The chocolate soy milk, energy bars and string cheese samples there will help sustain attendees as they make the rounds of booths.
    The expo is also a family-friendly environment, with an expanded youth activity center in one corner of the field house. Young people will be able to paint a canvas bag that they can keep and circulate an educational passport book.
    "There is a renewable energy scavenger hunt for the kids," said Peter Johnston of APS. "Kids will visit these companies, answer questions and get their passports stamped. If they answer correctly, there are prizes."
    Johnston and Janet Crow, both of the APS Technology Department, said children are most interested in biogas, the gas generated from the anaerobic digestion of agricultural and animal waste.
    "Did you know a Phoenix elephant's waste is worth 400 watts of electricity?" Crow asked. "A cow is 150 watts, chickens are 2 watts and a pig is 56 watts."
Source: Knight Ridder/Tribune Business News