From the US comes news that scientists at the Department of Energy’s Brookhaven National Laboratory and Los Alamos National Laboratory have fabricated transparent thin films capable of absorbing light and generating electrical charge over a relatively large area.
One important application of the new material could be when used to develop transparent solar panels or even windows that absorb solar energy to generate electricity.
The new material consists of a semi- conducting polymer doped with carbon- rich fullerenes. Under carefully controlled conditions, the material self-assembles to form a reproducible pattern of micron-size hexagon-shaped cells over a relatively large area – up to several millimetres.
This is the first report of the material that blends semiconductors and fullerenes to absorb light and efficiently generate charge and charge separation.
Scientists are convinced that combining various new traits and achieving large- scale patterning could enable a wide range of practical applications, such as energy-generating solar windows, transparent solar panels and new kinds of optical displays.
Hi-Tech Solution to Support Solar Production
Meanwhile, atomic layer deposition system designer and manufacturer Picosun, of Finland, has launched production of fully automated throughput batch reactors for solar power markets. Picosun’s batch reactors are suitable for high-volume crystalline silicon solar cell surface passivation. Despite the advent of new solar cell technologies during the last couple of decades, crystalline silicon solar cells are still used to generate 80% of global solar energy.
Picosun’s proprietary Atomic Layer Deposition (ALD) is suited for large- scale industrial applications. Because of its speed and cost-effectiveness, it repre- sents a potential challenge for present manufacturing methods. Significant absolute and relative efficiency improvements have been noted with silicon solar cell ALD passivation.
In the solar cell business, ALD tech- nology solutions offer performance gains for all sorts of cells. In particular, new cell technologies that are based, for example, on dyes, organic polymers and thin films require simple, cost-effective solutions, adaptable for large-scale production, that can improve efficiency and durability. ALD thin films, when located strategically on cells or panels, can prevent recombination, protect from corrosion, serve as encapsulants or replace toxic or costly cell materials.
Noted Picosun CEO Juhana Kostamo: “Our extensive know-how in ALD and experience of numerous ALD tool proto- types tested over the last three decades have been the necessary key for designing a fast and reliable batch ALD tool ena- bling high quality, low particle count and high throughput.
Solar Panels Follow the Light
‘Pictures of the Future – Spring 2011’ reports about the new software which enables the photovoltaic modules to precisely follow the sun.
The sun’s position varies depending on the time of day and year, so most sunlight hits solar cells mounted on fixed panels at an oblique angle. Maximum electricity yield is achieved only when sunlight strikes cells perpendicular to their surface.
With this in mind, Siemens has come up with software that allows photovoltaic modules on movable mountings to pre- cisely follow the sun.
The new system’s control software uses parameters such as longitude, latitude, and the exact time to calculate the sun’s position. Three-phase alternating current motors align the photovoltaic modules accordingly. They swivel the modules in a semicircle around the azimuthal support axis, tracking the sun’s daily course from east to west, and tilt the module around the zenithal axis, tracking the sun’s height according to the time of day and year.
The modules’energy yield is over 35% higher than that of fixed systems.