Cellule Grätzel. Un article de Wikipédia, l'encyclopédie libre. Une cellules Grätzel est un système photoélectrochimique inspiré de la photosynthèse végétale qui, exposé à la lumière (photons), produit de l’électricité. Elle est également appelée cellules à pigment photosensible et souvent désignée par l'acronyme dérivé de son appellation en anglais : dye-sensitized solar cell, DSSc, DSC voire DYSC).
Elle a été nommée ainsi en référence à son concepteur, Michael Grätzel, de l’École polytechnique fédérale de Lausanne. Principe de fonctionnement[modifier | modifier le code] Il s’agit d’un système photoélectrochimique, inspiré de la photosynthèse végétale, constitué d’un électrolyte donneur d’électron (analogue à l’eau dans la photosynthèse) sous l’effet d’un pigment excité par le rayonnement solaire (analogue à un pigment photosynthétique tel que la chlorophylle). Type de cellule réalisé à l'EPFL par Grätzel et O’Regan.
Fonctionnement d'une cellule Grätzel. Notes et références[modifier | modifier le code] Is the Secret to Cheap Energy Storage Hiding in Harlem? [Slide Show] Ensconced in a former warehouse in Manhattan's Harlem neighborhood, an energy start-up has equipment not typically associated with battery manufacture—restaurant-grade mixers, pasta-makers and even rolling pins. This kitchen equipment makes ingredients that the company hopes will turn the familiar alkaline battery into a cheap way to store the electricity from massive wind farms. Like many other battery start-ups, Urban Electric Power has survived so far on city and state business development grants for its Harlem location as well as research funding from the Advanced Research Projects Agency for Energy (ARPA–E).
But what also distinguishes Urban Electric from their peers (aside from the restaurant gear) became obvious during a recent tour of the new facility with Secretary of Energy Ernest Moniz—namely, the lack of glove boxes that fill other experimental battery shops. View a slide show of the makings of these alkaline batteries. "You can put it in the basement," adds Banerjee. Students in the Netherlands unveil a solar-powered family car. Will we ever be able to live in a world powered by the sun? Solar Team Eindhoven, made up of students from Eindhoven University of Technology in the Netherlands, has solved a crucial part of going solar: An solar-powered car that comfortably seats a family of four. Named Stella after the latin word for “star,” the proof-of-concept vehicle comes equipped with solar cells that actually collect more energy than is used by the car’s engine, sharing surplus solar energy back to the power grid.
The car’s development began just last September, and the group of 22 students across multiple disciplines of the Eindhoven University of Technology built the car from the ground up in only six months. The materials used on the Stella’s body – carbon and aluminum — work in combination with its bullet-like aerodynamic design to maximize efficiency without sacrificing space.
Check out a video of the Stella’s unveiling below: One year with solar energy at home: Mostly sunny! — Cleantech News and Analysis. Scientists work to build a better leaf. Researchers are analyzing the molecular pathways that plants use for photosynthesis. By Alan Boyle, Science Editor, NBC News Researchers have been trying for decades to improve upon Mother Nature's favorite solar-power trick — photosynthesis — but now they finally think they see the sunlight at the end of the tunnel. "We now understand photosynthesis much better than we did 20 years ago," said Richard Cogdell, a botanist at the University of Glasgow who has been doing research on bacterial photosynthesis for more than 30 years. He and three colleagues discussed their efforts to tweak the process that powers the world's plant life today in Vancouver, Canada, during the annual meeting of the American Association for the Advancement of Science. The researchers are taking different approaches to the challenge, but what they have in common is their search for ways to get something extra out of the biochemical process that uses sunlight to turn carbon dioxide and water into sugar and oxygen.
The engines available | Genoastirling. Electronic Projects. TripodTripod Mounts I am convinced that the best and strongest mount for PVs at ground level is one based on the design example of: poulektraxle * TraxlePoulek Solarby Martin PoulekGary A. Werner, President GWM CorporationPolar mount with tracker. The tripod support arrangement is very strong with light weight construction. The second image has mirrors to increase the concentration to 1.5X. aps * APS Solar's Pseudo Polar Axis "Tilt Tracker".Similar to Poulek Solar's Traxle, with a clockwork tracker. Powerlight PowerLightAn even bigger version, similar to Poulek Solar's Traxle. sunpowernellis * SunPower A huge field of true polar axis tripod solar tracking mounts at Nellis Air Force Base.36.258376,-115.052763 (SunPower purchased PowerLight.) EnergyoptionsEnergy Options PV Polar Axis Tripod Mount Energy Options has this very nice tripod mount for sale that uses a single axis tracker.
Gordon Glen Gordon's Pseudo Polar Axis Mounts. Mecasolar Video of MecaScrew Installation. szymanski Note! Note!! 1. George's Workshop Solar. RIBS - External ribs form the parabolic shape to the reflector sheet. There are seven ribs required for a single eight foot reflector or three ribs for a four foot reflector. I recommend MDO wood (weatherproof sign board) and suggest sources of supply (start with your local signmaking shop). The top inside curve should be accurately made and stable to within a millimeter to get the best results. With a bit of care, they can be machined easily to good tolerance and finish with a router and a template that you make. CNC You can use a CNC router, laser or water jet to make the ribs and hangers. Or make by hand using templates Rough blank shapes are cut with a jig saw to a pencil line traced from a template and then closer still with a band saw.
Vertical drilling is marked and center punched with the template. The plans show you in detail how to make high quality parts. With the methods described, it will take you about three and a half hours for each finished part with two coats of paint. Joule Unlimited: Fuel from Sun and Carbon Dioxide. Joule Unlimited, a start-up company based in Cambridge, Massachusetts, has developed a way to produce biofuel from genetically modified photosynthetic organisms in a bioreactor, using just sunlight and carbon dioxide. The process is called helioculture and the bioreactor is termed a solar converter. The process does not require freshwater resources or agricultural land, and does not need a biological intermediary such as algae, corn, switchgrass or biomass waste. As explained by Joshua Kagan in greentechmedia, after an interview with William Sims, CEO of Joule, the optical density is managed in the solar converter to optimize photosynthesis. The organisms have been genetically modified so that instead of using the sunlight and carbon dioxide to grow, they use it to produce fuel in a single, continuous process.
Joule's target is to be able to produce up to 15,000 gallons of biodiesel per acre per year at full-scale production. Scaling up: Joule funded for test tube biofuel | Cutting Edge. Startup Joule has secured the money to take its potentially breakthrough biofuel technology to a larger scale. The company today announced that undisclosed private and institutional investors led a $70 million funding to build a larger demonstration plant. The announcement was made at the Technology Leaders in Future Energy conference in Abu Dhabi.
Founding investor Flagship Ventures also joined the round. Founded in 2007, Joule took a clean-sheet approach to making biofuels which now are primarily made from corn or sugar cane. The fuel-making microbes grow in a solution in specially designed solar panel-like bioreactors. Dozens of biofuel companies have tried but not succeeded in making cellulosic ethanol from wood or other non-food sources at commercial scale. Today's funding will allow it to expand and operate a demonstration plant in Hobbs, N.M., starting this summer. A solar hot water collector that makes electricity, too | Green Tech. Startup GMZ Energy thinks solar hot water panels can pull double duty. The company today announced it raised $14 million in series C funding to commercialize a product that will draw electricity from solar hot water collectors.
It will also make small chips able to convert heat from car exhaust pipes and industrial machines into electricity. GMZ Energy, which was spun out of the Massachusetts Institute of Technology and Boston College in 2008 , has created an improved material for converting the energy in heat into electric power. The process works in reverse so an electric current will produce heat. Thermoelectric materials have been used for years in a few applications, such as heated seats in cars and portable coolers.
GMZ Energy claims that its nano-engineered materials make their use viable for many other uses, such as turning waste heat into usable energy.