Exchange traded funds tracking solar and clean energy stocks rallied more than 3% Tuesday after GT Solar International (NasdaqGS: SOLR) boosted its fiscal first-quarter outlook and raised its backlog expectations for the full year.

GT Solar shares were up more than 4%. The stock is held in Market Vectors Solar Energy (NYSEArca: KWT), iShares S&P Global Clean Energy (NasdaqGM: ICLN), Guggenheim Solar ETF (NYSEArca: TAN) and PowerShares Wilderhill Clean Energy (NYSEArca: PBW).

Guggenheim Solar ETF was down about 9% year to date heading into Tuesday’s action.

The earnings season for the solar sector “appears to be one of the more volatile periods in some time,” said analysts at Brean Murray.

The group faced a setback recently due to a weak forecast from LDK Solar (NYSE: LDK). [LDK, Trina Rain on Solar Energy ETFs]

Guggenheim Solar ETF

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