After announcing 30% tariffs on all imported c-Si solar panels in January, the U.S. Trade Representative (USTR) will officially exclude certain products from the import duties starting Sept. 19, 2018.

Officially excluded from the 30% solar panel tariffs:

45-W off-grid solar panels

4-W solar panels

60-W panels

120-W flexible and semi-flexible panels used for motor vehicles and boats

90-W frameless solar panels in colors other than black or blue

IBC and busbar-less solar cells

IBC and busbar-less solar panels

modules using only U.S.-made solar cells

The obvious winner in this situation is SunPower, which, although a U.S. company, manufactures/assembles its interdigitated back contact (IBC) modules in the Philippines and Mexico.

“With today’s decision that SunPower’s highly differentiated IBC cells and modules are excluded from tariffs, we are able to turn the page,” said SunPower Chairman and CEO Tom Werner. “SunPower can now fully focus our resources to deliver the best solar solutions to our customers, develop the next wave of solar technology through American research and development and invest in American solar manufacturing.”

The January solar tariff decision kicked off a trade battle between the United States and mainly China that had its latest development just yesterday with new 10% duties on imported Chinese goods, including solar inverters and AC modules. The initial 30% tariffs on solar panels affect imports from all foreign countries, and Chinese solar panels were hit with an additional 25% tariff last month.

USTR received over 50 requests for exemption from the 30% panel tariffs, some more serious than others. SunPower provided the most documentation to support exemption of its IBC solar cells used in high-efficiency modules. BayWa r.e. Solar Systems jointly filed with LG Electronics USA to request exclusion of all IBC solar modules, since LG and SunPower’s IBC modules were “functionally identical.”

The difference between SunPower and LG’s IBC modules (as stated by LG in USTR documents) is that SunPower uses copper plating to connect the interdigitated metal fingers while LG uses copper ribbons.

The official exclusion is for IBC panels with “more than 100 interdigitated fingers of tin-coated solid copper adhered to the back of the cell.” The phrase “tin-coated solid copper” is copied from SunPower’s exclusion request document. The “solid copper” reference may be why SunPower receives the tariff exclusion while LG does not.

SunPower announced in April it would acquire Oregon-based SolarWorld, in what seemed to be an increased effort to show the U.S. government that it is all-in on American manufacturing. The acquisition should be completed before the end of the year. Although its high efficiency panels are now excluded from the tariffs, SunPower still plans to produce its own modules in the Oregon plant, which was previously rated at over 500-MW capacity.

“SunPower’s 33 years of technology innovation and solar industry leadership are an integral part of the story around America’s energy evolution,” Werner said. “We appreciate the Administration’s thorough review and consideration on this matter and believe this outcome supports common goals of technology innovation, economic prosperity, energy independence and U.S. competitiveness in the global marketplace.”

LG also announced it would build its own 500-MW solar panel facility in Alabama to avoid some of the tariffs. LG is a South Korean company but has a significant presence in the U.S. residential and commercial markets.

We’ve been covering the affects of the solar panel tariffs since the beginning. Check out our recent news reports here, including an extended feature on foreign manufacturers setting up shop in the United States.

This story was updated 09/21/18 with more accurate information on LG and SunPower’s IBC module manufacturing processes.