Mark Halper reports a solar boom led investments in clean energy to the third highest quarter on record, to $41.7 billion for the 3 months ended June 30, according to London-based Bloomberg New Energy Finance.

Investments climbed 22% above the same quarter a year earlier, and were 27% higher than 2011’s first quarter.

Funding of solar thermal power plants contributed to much of the gain, the research company said.

It singled out the $2.2 billion BrightSource Energy raised for its 392-megawatt project in California’s Mojave Desert. Projects run by Juno Beach, Fla.-based NextEra Energy Resources, and by S. Africa’s Eskom Holdings Ltd. also received significant investments.

While clean energy investments surged, market gains fell. The WilderHill New Energy Global Innovation Index dropped by 13% in the same period, Bloomberg noted.

“The explanation is partly to do with ongoing investor worries, perhaps overdone, about future policy support, and partly to do with the fact that this is a highly competitive sector, in which costs are falling and high manufacturer margins are hard to sustain,” Bloomberg New Energy Financial Michael Liebreich said. As reported here, solar panel prices are free-falling.

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