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SolarCity sparked a “war” of high-efficiency solar panels

solarcity_copper_ridge_schoolEarlier this month SolarCity announced details of a new high-efficiency solar panel it plans on producing at its 1 GW module factory under-construction in Buffalo, NY. The company claimed that the module’s 22.04% efficiency was enough to make it the “most efficient rooftop solar module” ever made.  The claim apparently sparked a “war” of high-efficiency solar panels because in the week following the announcement two other solar panel makers claimed to have surpassed SolarCity’s record. A few days after SolarCity’s announcement, Panasonic claimed to have developed a new record-breaking solar module with 22.5% efficiency.

SolarCity’s claim has been verified by Renewable Energy Test Center, while Panasonic’s by the Japanese National Institute of Advanced Industrial Science and Technology. We might have an “every radio station is the number 1 radio station” situation here.

The confusion might be due to SolarCity claiming the best “rooftop solar panel” and Panasonic talking about a “commercial-sized” solar module. Also it would be fair to mention that Panasonic is only talking about a “prototype module”, while SolarCity announced that it will start production at its 100 MW pilot plant in Fremont by the end of the month and they already confirmed a cost of about $0.55 per watt for 355 watts panels.

A few days after Panasonic’s announcement, SunPower came out with a blog post claiming its X-Series solar panel is the “most efficient solar panels commercially available today”. The X-Series with a verified 21.5% efficiency was indeed the most efficient panel before SolarCity’s announcement earlier this month of 22.04%.

SunPower’s X-Series still has a nameplate value of 21.5%, but it now claims that “in some cases [they] are finding that these panels are exceeding 22 percent efficiency, as verified by the U.S. Department of Energy’s National Renewable Energy Laboratory”.

Until all those products hit the market it will be difficult to declare a winner, but consumers should appreciate these competing announcements nonetheless. The price of solar modules has been falling over recent years, but efficiency has been stuck between 15 and 18 percent for residential panels for quite some time now.  We might be witnessing early signs of an upcoming push toward the 20’s percentile of efficiency which will be great for distributed residential solar. The cost of installation will go down and consumers will be able to install more power on smaller roofs.

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  1. Zach - 7 years ago

    Meh. I think SunPower’s response is simply because SolarCity made a claim it wouldn’t have made if it had the same product. In other words, SolarCity theoretically took the #1 spot from SunPower, but not really. And may be the wording is just unclear at the start of your last paragraph, but the X-Series modules have been on the market for over 2 years (no need to wait for them to hit the market):

    Definitely some kudos to SolarCity (and I’m a shareholder, so am happy — but note that I’m also a shareholder of SunPower). But I think I’d be irritated if I were in SunPower’s shoes and would have done the same.

    As far as Panasonic’s press release, I imagine it was planned anyway, and Panasonic simply took the opportunity to announce it now, since SolarCity typically gets press for every little thing, and Panasonic could get more eyeballs by trumping SolarCity a few days later. It probably planned to announce the product once commercially available, but since SolarCity jumped the gun…

    I wouldn’t call any of that a war, but maybe some feel like it is. SunPower & Panasonic have been trading places at the top for years. SolarCity made a brave move by acquiring Silevo. Still waiting to see if it really rewards the company as much as intended.

    Plenty more to say on the differences between these products, but I need to get back to work. 😀

    • Fred Lambert - 7 years ago

      The question is why doesn’t SunPower get its nameplate efficiency rate updated then?


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