Frost: Nanomaterials, Cost-effective Manufacturing Key to Photovoltaic Technologies

November 3, 2006 // Published as a news service by IHS

There has been much concern over the emanation of harmful greenhouse gases from the use of fossil fuels, putting a heightened focus on developing renewable sources of energy and photovoltaics (PVs), which draw their energy from the sun and represent clean, easily renewable sources of energy.

According to Frost & Sullivan, in areas such as grid power and power for portable devices, PVs are considered a leading technology and will continue to be a research focus over the next 10 to 20 years.

Analysts said while silicon solar cells and thin film solar cells have dominated the solar cell industry, a third generation of solar cells made from nanomaterials look poised to foster "tremendous" advancements in the industry.

Nanomaterials can also have their orientation tuned to trap energy more efficiently than conventional materials, while displaying superior properties such as high strength and flexibility.

"Nanomaterials and quantum dot-based solar cells are expected to create a splash in the PV industry, if their powerful quantum effects are used effectively to tap the largely unexplored infrared region of the solar spectrum," said Frost & Sullivan research analyst Vijay Shankar Murthy. "Innovalight's new silicon ink technology is a step in this direction and could herald the foray of nanomaterials-based solar cells."

Nevertheless, solar cells based on nanomaterials are still in their inception stage and silicon and thin film PV technologies are likely to remain dominant over the next decade. Emerging silicon PV technologies include the Flatcon technology being developed by Concentrix Solar and the emitter-wrap through (EWT) solar cells being developed by Advent Solar.

Analysts said while Flatcon uses the Fresnel lens to efficiently concentrate light on the solar cell, and thereby finds potential applications in grid networks for remote locations, the EWT solar cell is basically a back contact solar cell that achieves up to 22% efficiency in power conversion.

On the thin film PV front, copper-indium-gallium-selenide (CIGS) thin films are the preferred choice of many manufacturers. Analysts said this is largely due to their higher efficiency and greater environmental friendliness when compared to the competitor - cadmium-telluride films.

Miasolé Corp.'s novel CIGS modules and Heliovolt’s field-assisted simultaneous synthesis and transfer (FASST) process that produces cost-effective, yet efficient solar cell modules are the noteworthy innovations anticipated in the future.

With respect to the major challenges, analysts said manufacturers of PV technologies are likely to be constrained by high costs. Manufacturing solar cells involves the use of sophisticated electronic wafer manufacturing techniques and electronic design automation tools. Employing these techniques on a large scale makes the process capital-intensive and contributes significantly to the cost per watt of electricity produced.

"This apart, present efficiency levels of solar cells do favor their full-scale commercial use," said Murthy. "Also, solar cells face formidable competition from other clean technologies such as fuel cells, wind turbines and microturbines, in their respective areas of application such as grid power, portable power and so on."

In order to overcome these restraints, analysts said it is important that solar cell manufacturers optimize their production capabilities to lower costs, while at the same time increasing the efficiency of individual solar cells and modules. Since the cost of manufacturing silicon and thin film PVs is quite high, manufacturers have to find ways of eliminating a few unnecessary steps in the process in order to make the final product cost-effective.

Source: Frost & Sullivan.