Despite a run-up in a few solar-energy stocks, there's still opportunity in the sector, Ben Kallo of R.W. Baird said Friday.
"SunPower, which is my favorite, is up over 400 percent this year," he said, noting that it had been a laggard all year.
"We've had a big move off the bottom. The past two years were terrible," he said. "A bubble was in 2007 when we were really focused on Europe. That was really the only market, Germany and Italy and Spain. Now, we have a global market, and it's a different business."
Kallo said that SunPower was in a competitive position, citing its profitable business, as well as its $1 billion of liquidity.
"SunPower is a business you can own long-term," he said. "First Solar, similar, but they're a one-trick pony, focused on the utility side of the business."
Still, the solar space was not in bubble territory, Kallo said. "We're in the third inning, maybe."
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Tim Seymour of EmergingMoney.com said that he owned SunPower and Trina Solar stock.
"SunPower, I love because of their exposure in emerging markets," he said.
Seymour also said that "some of these Chinese solar stocks have done this round-trip two times. So, Trina Solar was a $50 stock two different times in between trading down to $5."
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Seymour said that Chinese solar companies were now getting a handle on their previous oversupply issue.
"Profits are there, and valuations are not stretched," he said.