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Take an artificial pacemaker. This device transmits an electrical voltage to the biological pacemaker cells of the heart. In a healthy human, these pacemaker cells generate their own action potential, an electrical waveform of about 100 millivolts. This may not sound like much energy until we remember that this electrical potential is sustained across an insulating membrane only five nanometers thick. That is 5 billionths of a meter. So the energy of an action potential is almost 20,000,000 volts per meter. Compare this to the 12,000 volts per meter at a standard wall plug. Healthy pacemaker cells spark the electrical wave that drives heart muscle contraction. When these cells malfunction, an artificial pacemaker may be implanted to take over. Waves of electrical voltage generated at the metal lead of the artificial device cross over to living tissue and initiate normal muscle contraction.

Je ne sais pas si tu te rends compte mais un lingot permet de faire 4 panneaux solaires de 1m² qui produisent 4x130w et qui ont une durée de vie de 20ans. si tu n'utilises que les chutes de lingots, il faut 6 lingots pour faire 1 panneaux qui produira 130w avec une durée de vie de 20ans (pour faire un panneaux en poly silicium donc avec les chutes des lingots, il faut encore faire fondre les chutes 1400°C pendant quelques heures). Imagine maintenant l'énergie qu'il faut pour faire 4 panneaux solaire (9x24heures à 1200°C), l'énergie qu'il faut est beaucoup plus importante que ce que 4 panneaux de 130w pendant 20ans peuvent produire (et là je parle que de l'énergie). En gros un panneau solaire de 130w ne rembourse pas l'énergie qu'il a eu besoin pour être fabriqué  c'est bien le problème des média qui ne parlent que des bonnes choses de ces panneaux et qui arrive à faire croire à des personnes comme toi que c'est écologique.  

la plupart des panneaux solaires en silicium proviennent des déchets de l'industrie microélectronique

fabrique les panneaux solaires, les lampes à DEL, les processeurs,.... je vais parler du monde du silicium. La base de ces panneaux solaire est donc le cristal silicium pur, pour obtenir ce silicium on met du sable (SiO2) dans un creusé et on le fait fondre à 1400°C. Une fois le silicium  fondu et les molécules d'oxygène évacué, on plonge un germe de cristal de silicium dans le creusé que l'on tire tout doucement (1mm/15min) afin d'obtenir un cristal du silicium.   Il faut environs 24 heures pour obtenir un lingot de silicium et pendant ce temps le creusé doit resté à 1400°C. S’en suit une purification du lingot, on recuit le lingot 5 à 6 fois à 1000°C pendant à chaque fois 24 heures cela fait beaucoup beaucoup d'énergie et donc beaucoup beaucoup de CO2.   Une fois le lingot pur obtenu, il faut le découper et le polir (là on utilise beaucoup d'eau il ne faut pas que le silicium chauffe). S’en suit alors la réalisation du système, là il s’agit d'une répétition de dépôt de résine toxique, cuisson, attaque chimique (acide fluoridrique), dépôt chimique (silane SiH4 et Tétrafluorosilane SiF4 qui produit des gaz fluoré très toxique avec une duré de vie de 150ans) généralement l'opération est répété 40 fois environ. Après les systèmes obtenu il faut les découpés, mettre dans des boitiers,...  Bien sur, je ne parle pas du transport car la plupart des systèmes sont fabriqué en Asie, il y a aussi des à côté comme les salles blanches,.... les ordinateur qui tourne 24 heures sur 24 7jours /7.  Il faut 1 lingot pour fait 4 panneaux de 1 m²

The next Virtual Energy Forum will take place on December 10th and 11th 2008 with all-new speakers, track presentations, virtual booths and information resources from the top institutions and individuals in the field.

represents nothing less than a bold invitation to the entire Notre Dame family to embark upon a thoughtful and comprehensive course of sustainability in our personal lifestyles, our institutional practices, our intellectual life and research, and our civic commitments.

This one’s been swirling around for a tick, but Leviathan Energy’s brilliant new turbine is just too good to pass up. Showcased at the Cleantech Forum in California, this contraption would reportedly generate power from the downward movement of water through pipes in a municipal system. In other words, there’s potential to conjure up energy from simply flushing one’s toilet. Of course, there’s nothing revolutionary about yet another hydroelectric generator, but using such a device to grab power from such a dirty place takes things to a whole ‘nother level.

Project Better Place, owned by Israeli-American entrepreneur Shai Agassi, will provide lithium-ion batteries to power the cars and the infrastructure to refresh or replace them. One battery will enable the cars to travel 124 miles per charge. Project Better Place will install parking meter-like plugs on city streets and construct service stations along highways to replace the batteries. [2] Renault-Nissan will build the new cars and will offer a small number of their existing electric models, such as the “Megane” sedan, at prices roughly comparable to gasoline models. To promote this form of environmentally efficient transportation, the Israeli government cut the tax rate on cars powered by electricity to 10 percent (from 79 percent on ordinary cars) to encourage consumers to buy the vehicles once they become available. [3] This initiative will offer consumers an inexpensive car for which they will pay a monthly fee based on expected mileage.

Leading stakeholders from across the EU met today with Consumer Commissioner, Meglena Kuneva, and Energy Commissioner, Andris Piebalgs, to reinforce and promote the rights of EU energy consumers. Stakeholders gave their support to the process launched by the Commission to better implement these rights and better inform consumers. The basis for this process will be the Citizens' Energy Forum, building on the measures proposed in the "Third Energy Package".

Mirror, mirror on the wall, who's the greenest of them all? Well, if you're in the retail sector the obvious answer to that is Wal-Mart. There was much skepticism initially of Wal-Mart's attempts to go green. Many believed its quest to reduce energy consumption, embrace rooftop solar systems and clean up its transport fleet was yet another attempt at feel-good marketing -- a bid to win over consumers who believed Wal-Mart was an evil retail monster aimed at taking over every small town in America. At the recent Cleantech Forum in Toronto, Rand Waddoups, senior director of corporate strategy and sustainability at Wal-Mart, admitted that the retailer's green strategy was initially adopted from a defensive posture. "We started by saying 'this could be a real problem for us, we need to understand how big of a problem this could be.' Over time, we realized this wasn't a problem, it was a real opportunity for us."

the new international forum links up the EU Commission and seven member states (France, Germany, the UK, Italy, the Netherlands, Ireland and Portugal) with eleven US and Canadian regional states (the likes of New York, Maine, California and British Columbia) to exchange information and best practices about their efforts to create carbon markets through a cap-and-trade system. The bad news: where are the other 20 EU member states? And what about other federal governments such as the US, Russia, China or India?