Day4 Energy’s Proprietary Module Technology Paves the Way for Metallurgical Silicon Solar Cells

Day4 Electrode with Integrated Shading Protection Maximizes Long-Term Performance of UMG PV Cells

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Burnaby, BC – August 7, 2008 - Day4 Energy Inc. (TSX: DFE), a leading manufacturer of high performance, cost-effective solar electric modules, announced today that it has successfully developed and tested a proprietary PV module technology specifically designed for application with solar cells based on Upgraded Metallurgical Grade (UMG) silicon material. Once commercialized, UMG silicon technologies are widely believed to become a viable source of low cost alternative silicon material for solar industry. However, UMG silicon processing presents a number of technical challenges across the industry’s value chain. Day4’s proprietary technology is designed to address specific requirements of UMG silicon based solar cells and is expected to offer significant cost reduction potential for solar power generation.

The company has used its proprietary Day4 Electrode and distributed by-pass diode technologies to integrate shading protection directly into the solar cells as opposed to the traditional approach that calls for by-pass diodes placed in the centralized junction box area on the back of the solar module. Due to the inherent flexibility of Day4 Electrode integrated by-pass diode technology, shading protection can now be distributed through-out the solar module reducing product sensitivity to changing solar illumination conditions and partial solar module shading in particular. While the technology is certainly applicable to all types of PV cells it is particularly relevant for UMG silicon based solar cells as it addresses one of the key issues of commercial UMG silicon based solar modules – increased sensitivity and potential danger to PV module integrity at the time of partial module shading when compared to conventional crystalline silicon solar module technology.

“It is known that UMG based solar cells typically have substancially lower shunt resistance and a corresponding lower value of breakdown voltage compared to conventional solar grade multicrystalline solar cells. This fact imposes a limitation on the maximum number of solar cells that can be connected in series in the solar module in order to prevent irreversible breakdown in case of partial module shading during operation.” says Professor Leonid Rubin, chief technology officer of Day4 Energy. “Our low cost integrated Day4 Electrode by-pass diode technology eliminates this problem and removes some of the existing prejudice against wider employment of this potentially prospective material.”

UMG silicon technology for manufacturing silicon ingots and wafers is widely believed to offer significant potential for cost reduction for the PV industry as a whole. With recent progress made by a number of companies at the silicon purification level, UMG silicon material is starting to make its way into the PV cell production lines. At the same time, PV module technology requires its share of modifications in order to successfully utilize these new UMG silicon based PV cells without jeopardizing the long-term integrity of the final product. Day4’s new technology addresses these issues and removes one of the key roadblocks on the way to implementation of UMG silicon solar cells in large-scale commercial solar module manufacturing. The technology is ultimately enabled by a combination of the company’s proprietary Day4 Electrode technology for contacting and interconnecting solar cells with a proprietary low cost by-pass diode design. The company has applied for patent protection in connection with this invention.

About Day4 Energy:
Headquartered near Vancouver, British Columbia, Day4 Energy Inc. (TSX: DFE) designs, manufactures and sells photovoltaic (PV) modules based on its patented Day4 Electrode technology, a proprietary method of contacting and interconnecting solar cells that produces PV panels of high power density, increased lifetime and uncompromised aesthetic appearance. Day4 Energy partners with the industry's leading PV cell producers to deliver IEC- and UL-certified commercial and residential solar products to customers throughout Europe and North America.

www.day4energy.com

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Press Contact:
Rosalind Jackson
Antenna Group (for Day4 Energy)
415-977-1923
rosalind@antennagroup.com

Investor Contact:
Cory Pala
416-657-2400
CPala@Day4Energy.com