About SLIVER


The award-winning SLIVER technology was invented and developed at the Australian National University’s Centre for Sustainable Energy Systems with financial support from Origin Energy. SLIVER technology comprises SLIVER panels/modules and SLIVER cells – the building blocks of SLIVER panels. SLIVER cells are substantially thinner than most solar cells yet highly efficient.

The SLIVER cell process uses an innovative micromachining technique to form deep narrow grooves perpendicular to the wafer surface – effectively using the 3 dimensions of the wafer whereas conventional processing is all on the wafer surfaces. The grooves are typically less than 40 microns in width on a 1-2mm thick silicon wafer. The result of this micromachining is a large number of thin (~50-80 microns) silicon strips in the centre of the wafer, held together by the surrounds of the wafer. On 1-2mm thick, 150-200mm diameter wafers, these strips typically are approximately 600-800 mm long, 1-2mm wide (wafer thickness) and 50-80 micron thick. The SLIVER cells are developed on these silicon strips. Cell processing is completed while the silicon strips are still supported by the silicon substrate at the edge of the wafer. Far fewer wafers need to be processed to form SLIVER panels than for conventional crystalline technology because so many cells are formed on each wafer. The size, thickness and bifacial nature of the cells create the potential opportunity for them to be used in a wide variety of panel/module architectures and applications.

SLIVER cells
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Radically different in size and shape

SLIVER cells also differ radically from conventional solar cells in size and shape. They are long, ultra thin, quite flexible, perfectly bifacial and have a high power-to-weight ratio. This allows considerable flexibility in module design and opens up possibilities for a number of new and innovative applications in the future, includin building integrated products BIPV and semi transparent flexible modules.

Dramatically reduces expensive silicon use

SLIVER technology uses the lowest amount of mono/poly crystalline silicon of all conventional silicon wafer technologies. We are working toward it delivering commercially competitive cell and module efficiencies. SLIVER cells are formed on fewer wafers than those required for conventional solar panels. Once released, we expect SLIVER panels to be priced at current market prices.

Module efficiency and transparency can be varied when SLIVER cells are spaced out

Using a highly reflective lambertian (scattering) layer at the rear of the module, the narrow width and bifacial nature of the SLIVER cells enable them to be spaced, providing a reduction in silicon use further, with only a small fraction of light escaping from the module. These features can be exploited in novel module designs in which 50% or less of the module surface is covered with cells, yet up to 85% of the incident light is still captured by the cells.

Removal of the lambertian reflector opens up a number of opportunities in semi-transparent applications.

For example, modules for architectural applications could one day be readily fabricated with any desired degree of transparency.

On the other hand, if we make SLIVER modules with 100% coverage – i.e. no gaps between them, the bifacial nature of the cells is not utilised, but the efficiency is increased.

We are now investigating the best coverage: efficiency ratio which our first commercially available product will be.

lambertian reflector
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The perfectly bifacial response gives greater energy output

For applications where there is relatively little obstruction of sunlight, the bifacial nature of SLIVER cells confers a substantial advantage over conventional monofacial modules in terms of annual energy production for a variety of mounting configurations. This feature, combined with the option for one day producing transparent SLIVER modules, allows for novel applications in road sound barriers and other building applications.

A low temperature coefficient means higher module efficiencies

If SLIVER modules are produced with a gap between each SLIVER cell, the low absorptivity of the SLIVER module, due to the gap between encapsulated cells, allow each SLIVER panel to run around 5º-6º C cooler compared to conventional silicon PV modules. Testing confirms that modules exhibit a higher efficiency, with a low voltage temperature coefficient of -2.0mV/ºC.

Additionally SLIVER cells are more tolerant to partial shading than conventional modules.

SLIVER cells are more tolerant to partial shading than conventional modules
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Technical papers