NEW YORK ( Karvy) -- GT Solar ( SOLR), LDK Solar ( LDK) and Yingli Green Energy ( YGE) emerged as top gainers last week, while InterOil ( IOC), McMoRan Exploration ( MMR) and TransAtlantic Petroleum ( TAT) led the losers' list.

GT Solar gained 9.8%, topping the list of energy gainers. During the week, the company announced a new DSS650 Multicrystalline Ingot Growth System. Tom Gutierrez, GT Solar's president and CEO, said in a press release, "GT Solar continues to actively invest in advanced technologies that deliver value to our customers. Our field-tested DSS650 sets a new standard for cost-effective, high volume, multicrystalline silicon ingot growth systems greater than 600 kilograms, which help PV manufacturers lower their production costs and improve their competitive position." Meanwhile, the company has received a $33.3 million order for sapphire crystallization from South Korea-based OCI.

Other solar stocks LDK Solar, Yingli, Trina Solar ( TSL) and First Solar ( FSLR) advanced around 6.8%, 6.7%, 4.3% and 4.1%, respectively.

EnCana ( ECA) rose 5%. During the week, Western Gas Partners ( WES), a subsidiary of Anadarko Petroleum ( APC), agreed to purchase Encana's Ft. Lupton processing plant in the DJ Basin of northeastern Colorado for $303.3 million.

Nexen ( NXY) advanced around 3.8%, after FirstEnergy Capital raised the stock to market perform. Analysts at Haywood Securities, however, downgraded the stock to sector perform. Meanwhile, Nexen announced it will sell its 65% stake in chemical company Canexus for C$477.1 million ($481 million) to a syndicate of underwriters.

French oil giant Total ( NXY) rose around 3.6% last week. Total Capital Canada and Total Capital, units of Total, sold around $2 billion of notes in a three-part offering. In the penultimate week, Total acquired interests in four exploration licenses in Argentina, in partnership with YPF ( YPF), to appraise the shale gas potential of these assets.

Cabot Oil & Gas ( COG) gained 3% after Morgan Stanley upgraded the stock to overweight with a $45 price target, implying a 15.1% upside from the current level.

Energy giants Exxon Mobil ( COG), Royal Dutch Shell ( RDS.A), Sunoco ( SUN) and Chevron ( CVX) posted gains of 3%, 2%, 1.9% and 1.7% last week, respectively.

Eni ( E) and El Paso ( EP) were up 2.9% and 2.8% during the week, respectively. RBS upgraded Eni to buy from hold, while Citi raised El Paso to buy from hold.

Occidental Petroleum ( OXY) surged around 1.6% after signing an agreement with the Abu Dhabi government to develop the Shah natural gas field.

Other winners include Precision Drilling ( PDS), Noble Energy ( NBL), EOG Resources ( EOG) and Penn West Energy Trust ( PWE), up 4.7%, 4%, 3.9% and 3.5%, respectively.

InterOil was the top loser, down 10.4%, falling below its 50-day moving average on concerns of potential project delays. McMoRan Exploration lost 10.1% after fourth-quarter losses widened due to charges and write-downs.

Teekay LNG Partners ( TGP) and Petrohawk Energy ( HK) shed 6.8% and 6.7% last week, respectively. Citi cut Teekay to hold from buy. Tudor Pickering downgraded Petrohawk to hold from buy.

Rosetta Resources ( ROSE) declined 5.8% after Howard Weil cut the stock to market perform while cutting the rating to trim from hold.

DCP Midstream Partners ( DPM) dipped 5.3%, despite receiving an upgrade to buy at Citi. During the week, DCP signed a long-term gas gathering, processing agreement with Pioneer Natural Resources ( PXD), Reliance Eagleford Upstream and Newpek.

Among other losers were Petrobras Energia Participaciones ( PZE), SandRidge Energy ( SD), Swift Energy ( SFY), Cheniere Energy Partners ( CQP) and Cobalt International Energy ( CIE) dropping around 7.4%, 7%, 6.2%, 6.1% and 6.1%, respectively.
This commentary comes from an independent investor or market observer as part of TheStreet guest contributor program. The views expressed are those of the author and do not necessarily represent the views of TheStreet or its management.