New Industry Products

Mitsubishi Electric Making High-Output Solar Panels For Major Overseas Markets

September 13, 2009 by Jeff Shepard

Mitsubishi Electric Corp. announced the launch of ten new models of photovoltaic (PV) modules – five for the European market and five for North America and Asia. The new lineup comprises modules with outputs of 210, 220, 225, 230 and 235W. Shipments will begin on January 15, 2010.

The new high-output modules use lead-free solder and incorporate PV cells with four bus bars. Using the new cells in combination with an increased module size achieves a power output of up to 235W per module. Larger output means that fewer modules are needed to build a system, helping to reduce total system cost.

By increasing the number of bus bars from two to four, the internal resistance in each PV cell has been reduced, increasing individual cell output by 3% compared to those used in Mitsubishi Electric’s previous models. To use four bus bars, however, each bus bar needs to be narrowed so that the cell can collect enough sunlight, which makes it difficult to connect each cell in the interconnecting wire soldering process with automated equipment. Mitsubishi Electric has overcome this difficulty by developing a high-quality graphic sensing technology that increases the accuracy in cell alignment.

By increasing the number of cells used in each module from 50 to 60 in addition to the use of four-bus-bar cells, module output power increased by up to 24% per module compared to Mitsubishi Electric’s 190W module. As a result, the number of modules needed to build a system can be reduced, saving on installation parts and labor costs.

The newly designed frame can endure force of approximately double that of Mitsubishi Electric’s previous models. Even with their larger size, the new models have passed the IEC static load test of 5400Pa, which is a standard for PV module performance established by the International Electrotechnical Commission. The new frame has also been designed to facilitate a wider variation of installation methods.

Mitsubishi Electric has developed a 4-layer junction box based on the company’s current triple-layer junction box design, increasing the module’s overall safety and reliability. UL V-0 certified potting material, a metal barrier cover, and a plastic resin cover were used to cover the electrified area inside the junction box. In the new design, a 4th layer, an extremely heat-resistant and flame-retardant sheet, was added to the inside of the metal cover.

Like previous Mitsubishi Electric PV modules, the new models continue to use only 100-percent lead-free solder, for less environmental impact than traditional PV modules.