pv magazine: SunPower is pivoting towards more conventional cell technologies and shingled cell modules. Why do you make this change?
Josh Moore: The Performance Series panel delivers a strong value proposition to customers who have available space to meet their solar energy production needs with a lower efficiency panel. By using front contact cells, SunPower is leveraging the commodity cell market and providing our customers with a superior panel design. This also allows SunPower to quickly scale module manufacturing to meet growing market demand.

For large solar plants, how much is the LCOE reduced compared to your modules with back contact cells? Is there still an advantage when using the back-contact cells, and for which applications do you still recommend those?
SunPower E-Series and X-Series solar panels remain the right choice for customers who want the highest efficiency and quality for which SunPower is known. Often, we recommend those products for space-constrained projects. P-Series serves customers who want reliability and performance at competitive cost. Both offer long term performance, based on SunPower’s 30+ years innovating solar technologies.

In your P-Series you can use different p-type cells, standard, PERC or heterojunction. Which is the most cost efficient at the moment, and do you think this will change?
One of the benefits of the P-Series technology is flexibility of using almost all front contact cell technologies. At the moment, p-type multi and mono PERC cells provide the best economics.

What is/was the main technological challenge for developing shingled modules? What is particularly innovative?
One of the key challenges to developing any new solar panel technology is ensuring a robust and reliable design that will survive in a variety of harsh climates for 25 years. SunPower P-Series panels were recently recognized as a Top Performer in the DNV-GL Module Reliability Scorecard, proving this new panel is at the top of its class.

By using shingled modules, you increase the module efficiency, but at the same time you’re “wasting” cell area. Why is it nevertheless a cost advantage compared to standard cells?
By designing out several weak points typically found in a conventional module, like the copper busbars and solder joints, we have also reduced the cost of the module. In a shingled cell module, there is a small portion of the cells that are not exposed to sunlight, but that portion is used to create the contact to the neighboring cell. By increasing the module efficiency relative to a three or four busbar module, the rest of the module bill of materials and manufacturing cost is leveraged down, resulting in a lower cost design.

How much P-Series modules you have already sold and what is your production capacity?
We haven’t publicly discussed the sales volume. We are pleased with the ramp of our P-Series modules and we remain on track to reach 600 MW capacity by the end of the year.