Spark EnergyInc. saw the biggest growth in short interest amongtop 10 S&P Global Market Intelligence-covered power and natural gascompanies during the second half of June, with shorts surging 687 basis pointsto 10.62% of its shares held short.

Dynegy Inc.came in second on the list, adding 594 basis points of short interest to landat 12.32% of shares held short between June 15 and June 30. At the start of theperiod, Dynegy closeda $460 million tangible equity units offeringto help fund its purchaseof a 9,058-MW portfolio of fossil power plants in the U.S. from .

TerraFormPower Inc. secured the third spot, followed by andPattern Energy Group Inc.,respectively.

Turning to the list of short interest decliners, saw the steepest declinein short interest, with its short interest position dropping 124 basis pointsto 1.80% of outstanding shares.

TECO EnergyInc., which was acquiredby Emera Inc. onJuly 1, came insecond on the list and shed 96 basis points of short interest to land at 3.12%of shares held short.

Other companies featured on the list included , and ,respectively.

SolarCityCorp. remains the most-shorted stock among the power and naturalgas companies, with 27.74% of shares held short at June 30, up from 27.68% atJune 15. SolarCity was followed by TerraForm Power, Dynegy and Pattern EnergyGroup, respectively.

Among the S&P Global Market Intelligence-covered coalcompanies, bankruptPeabody Energy Corp.saw the largest short-interest drop as of June 30, with shorts falling 638basis points to 22.65% of its shares held short, also making it the mostshorted energy stock during the period.

Cloud PeakEnergy Inc. came in second on the list and shed 558 basis points ofshort interest to 20.43% of outstanding shares, followed by and ,respectively.