A research group at the University of Tokyo and Sharp Corp developed a quantum dot-type photovoltaic (PV cell with a high efficiency.
Its cell conversion efficiency is 18.7% without light condensing and 19.4% at the time of 2x light condensing. The research group is led by Yasuhiko Arakawa and Katsuaki Tanabe, who are professor and specially-appointed associate professor, respectively, at the Institute for Nano Quantum Information Electronics, the University of Tokyo.
The 18.7% efficiency is the industry’s highest efficiency for a quantum dot-type PV battery that is not concentrating light, Arakawa said. Before the achievement was made, the highest efficiency had been 18.3% achieved by a research group at the Russian Academy of Sciences.
The latest quantum dot-type PV battery was developed by using the “intermediate band method,” in which conversion efficiency is improved by forming a superlattice structure (in which quantum dots are three-dimensionally arranged) and a miniband (intermediate band) that absorbs infrared light.
Twin Creeks, a solar power startup that emerged from hiding today, has developed a way of creating photovoltaic cells that are half the price of today’s cheapest cells, and thus within reach of challenging the fossil fuel hegemony. The best bit: Twin Creeks’ photovoltaic cells are created using a hydrogen ion particle accelerator.
3-millimeter-thick silicon wafers are placed around the outside edge of the big, spoked wheel. A particle accelerator bombards these wafers with hydrogen ions, and with exacting control of the voltage of the accelerator, the hydrogen ions accumulate precisely 20 micrometers from the surface of each wafer. A robotic arm then transports the wafers to a furnace where the ions expand into hydrogen gas, which cause the 20-micrometer-thick layer to shear off. A metal backing is applied to make it less fragile (and highly flexible, as you see on the right), and the remaining silicon wafer is taken back to the particle accelerator for another dose of ions. At a tenth of the thickness and with considerably less wastage, it’s easy to see how Twin Creeks can halve the cost of solar cells.
Twin Creeks Ion Technology
First Solar and Suntech led in PV module manufacturing in 2011, with both reaching approximately 2 GW of module production, according to Lux Research’s latest Solar Supply Tracker.
Crystalline silicon module prices continue to be at a record low, the report adds. Tier-one manufacturers are selling at around $0.90/W, while tier-two and tier-three manufacturers have sold product at even lower rates in order to burn through their inventories and survive the current market conditions.
The top 10 companies added up to 12.5 GW of module production – 44% of the 2011 total global module production.