First Solar falls 10.3% to a 52-week low of $172; borrowing costs explain only part of the solar selloff

First Solar shares fell 10.32% on Thursday to close at $172.16, down from $191.97, according to Nasdaq.com data. The stock traded as low as $170.80, below its previous 52-week low of $182.99, and about 6.36 million shares changed hands, close to three times its average volume of about 2.2 million. The drop took First Solar's market value to about $18.5 billion.

Seeking Alpha and 24/7 Wall St. both framed the day as a solar selloff driven by high borrowing costs, which matter to an industry that pays for nearly everything up front and earns it back over decades. That is a real pressure. It does not fully explain Thursday.

The selloff was not even

If rates alone were driving it, you would expect the two tracker makers, which sell into the same utility-scale projects as First Solar, to move much closer to it. Nextracker fell 2.25% and Array rose. Sunrun, the name most directly tied to consumer financing, fell hard, which does fit the rate story. First Solar fell the most of any of them. 24/7 Wall St. itself said the immediate catalyst for First Solar "remains unclear." We found no company announcement or SEC filing from First Solar on Thursday.

The stock was already sliding. It closed at $209.03 on September 11, so it is down about 17.6% in two weeks and about 46% below its 52-week high of $320.95. On September 16 it fell 5.6% after First Solar withdrew a Section 337 patent complaint at the U.S. International Trade Commission against makers of TOPCon panels, a step 24/7 Wall St. reported the company called procedural. Traders have been weighing what that means for competition from imported panels.

What the rate move does to a solar project

The rate pressure is still worth putting in numbers. The 10-year Treasury yield closed Thursday at 5.18%, up from 3.97% at the end of February, according to the Treasury's daily curve. Project loans are priced off rates like that, plus a spread.

As an illustration: on $100 million of 20-year amortizing debt, annual payments are about $8.72 million at 6% and about $9.44 million at 7%. One percentage point adds roughly $720,000 a year, or 8%, to debt service, and the project's power price has to cover it. For utility-scale solar, where there is no fuel bill to trim, that is how higher rates reach panel orders: developers either get a higher power price from the buyer or delay the project. The same logic hits a commercial rooftop job for a warehouse owner or a farm financing panels over 20 years.

What traders are watching

Whether Thursday's volume marks forced selling or a change in how investors see First Solar's position against imported panels is the open question. Treasury yields and any company comment on the patent withdrawal are the two things most likely to answer it. Chart: 10-year T-note.

Sources: Nasdaq.com, Seeking Alpha, 24/7 Wall St., U.S. Treasury. Debt-service figures are illustrative arithmetic by The Company Chronicle. This is market information, not investment advice.