Thin-Film Solar with High Efficiency  

Posted by Big Gav in ,

Technology Review has an article on thin film solar company Solexant's process for "printing inorganic solar cells with nanomaterials" - Thin-Film Solar with High Efficiency.

Solar cells made from cheap nanocrystal-based inks have the potential to be as efficient as the conventional inorganic cells currently used in solar panels, but can be printed less expensively. Solexant, a company in San Jose, CA, is currently manufacturing solar cells to test the technology. In order to compete with other thin-film solar companies, Solexant is banking on simpler, cheaper printing processes and materials, as well as lower initial capital costs to build its plants. The company expects to sell modules for $1 per watt, with efficiencies above 10 percent.

The company has licensed methods for growing nanocrystals and making them into inks from Paul Alivisatos, professor of nanotechnology at the University of California, Berkeley and interim director of the Lawrence Berkeley National Laboratory. (Alivisatos is on Solexant's board of directors.) Alivisatos says the advantage of these materials is their potential to combine low cost with high performance. Solar cells made from crystalline silicon are efficient at converting sunlight into electricity, but they're expensive to manufacture. To bring down the cost, companies have been developing thin-film solar cells from semiconductors that don't match crystalline silicon's performance but are much less expensive to make.

Solexant's goal is to make cheap thin-film solar cells with relatively high efficiencies. It would not disclose what the nanoparticle inks are made of, but the company says they are suspensions of rod-shaped, semiconducting nanocrystals that are four nanometers in diameter and 20 to 30 nanometers long. The Solexant cells are printed on a metal foil as the substrate. Nanocrystal films are simple to print but have poor electrical properties. Electrons tend to get trapped between the small particles. "The trick with these cells is how to deposit the materials on the fly in a way that makes a very conductive surface," which in turn ensures decent light-to-electricity conversion, says Alivisatos. Solexant begins with nanocrystals because they're easier to print, and heats them as they're printed, causing them to fuse together into larger, high-quality microcrystals that don't have as many places for electrons to lose their way.

The remaining parts of the solar cell, including the electrical contacts and a light-absorbing layer, are also printed on the flexible metal films. This process allows Solexant to print very large areas. When complete, the cells are cut and then topped with a rigid piece of glass.

Making the entire cell using a roll-to-roll process gives the company an advantage over other thin-film photovoltaic companies that print on glass, which is heavier and limited to smaller areas, says Solexant CEO Damoder Reddy. "The cost benefit is dramatic, allowing us to produce cells for 50 cents a watt," he says. First Solar, a thin-film company that uses vacuum deposition to print its cells onto glass, has manufacturing costs of 85 cents per watt. Nanosolar, another company making nanocrystal solar cells, uses a different semiconductor that requires chemical reactions to take place during printing, which increases the complexity and expense of the process. "We print a preformed semiconductor," which eliminates such steps, says Reddy.


Post a Comment


Locations of visitors to this page

blogspot visitor
Stat Counter

Total Pageviews




Blog Archive


australia (614) global warming (413) solar power (388) peak oil (349) renewable energy (282) electric vehicles (236) wind power (190) ocean energy (164) csp (158) geothermal energy (144) solar thermal power (144) smart grids (140) tidal power (137) oil (136) solar pv (132) coal seam gas (131) energy storage (130) nuclear power (127) lng (116) china (115) iraq (113) geothermal power (112) green buildings (110) natural gas (110) agriculture (90) oil price (80) biofuel (78) smart meters (72) wave power (72) uk (68) electricity grid (67) coal (66) energy efficiency (64) google (58) bicycle (51) internet (51) shale gas (49) surveillance (49) big brother (48) food prices (48) thin film solar (42) tesla (41) biomimicry (40) canada (40) scotland (38) ocean power (37) politics (37) shale oil (37) new zealand (35) air transport (34) algae (34) water (34) concentrating solar power (33) arctic ice (32) queensland (32) saudi arabia (32) california (31) credit crunch (31) bioplastic (30) offshore wind power (30) population (30) cogeneration (28) geoengineering (28) batteries (26) drought (26) resource wars (26) woodside (26) bruce sterling (25) censorship (25) cleantech (25) ctl (23) carbon tax (22) economics (22) exxon (22) limits to growth (22) buckminster fuller (21) distributed manufacturing (21) iraq oil law (21) coal to liquids (20) indonesia (20) lithium (20) origin energy (20) brightsource (19) rail transport (19) ultracapacitor (19) santos (18) ausra (17) electric bikes (17) michael klare (17) atlantis (16) cellulosic ethanol (16) collapse (16) iceland (16) mapping (16) ucg (16) bees (15) concentrating solar thermal power (15) ethanol (15) geodynamics (15) lithium ion batteries (15) psychology (15) al gore (14) brazil (14) bucky fuller (14) fertiliser (14) ambient energy (13) biodiesel (13) carbon emissions (13) cities (13) investment (13) kenya (13) matthew simmons (13) public transport (13) biochar (12) chile (12) desertec (12) internet of things (12) otec (12) texas (12) victoria (12) big oil (11) cradle to cradle (11) energy policy (11) hybrid car (11) terra preta (11) tinfoil (11) toyota (11) amory lovins (10) antarctica (10) fabber (10) gazprom (10) goldman sachs (10) gtl (10) severn estuary (10) volt (10) afghanistan (9) alaska (9) biomass (9) carbon trading (9) distributed generation (9) esolar (9) four day week (9) fuel cells (9) jeremy leggett (9) pge (9) sweden (9) arrow energy (8) eroei (8) fish (8) floating offshore wind power (8) guerilla gardening (8) linc energy (8) methane (8) methane hydrates (8) nanosolar (8) natural gas pipelines (8) pentland firth (8) relocalisation (8) saul griffith (8) stirling engine (8) us elections (8) western australia (8) airborne wind turbines (7) bloom energy (7) boeing (7) bolivia (7) chp (7) climategate (7) copenhagen (7) vinod khosla (7) apocaphilia (6) ceramic fuel cells (6) cigs (6) futurism (6) jatropha (6) local currencies (6) nigeria (6) ocean acidification (6) scenario planning (6) somalia (6) t boone pickens (6) space based solar power (5) varanus island (5) garbage (4) global energy grid (4) kevin kelly (4) low temperature geothermal power (4) oled (4) tim flannery (4) v2g (4) club of rome (3) norman borlaug (2) peak oil portfolio (1)