NEW YORK (TheStreet) -- Teekay Offshore Partners (TOO), Chesapeake Midstream Partners (CHKM), Plains Exploration & Production (PXP) and Williams Partners (WPZ) were top performers last week, while ReneSola (SOL), JA Solar (JASO) and Trina Solar (TSL) lost substantial ground.Last week, Teekay Offshore Partners topped the charts, jumping 4.3%, while Chesapeake Midstream Partners rose 4.2%. Plains Exploration & Production advanced 3.9% after analysts at Macquarie upgraded the stock to outperform from neutral and lifted its 12-month price target to $57 from $37. Williams Partners rose 3.7% following a positive assessment in a recent report by Bank of America/Merrill Lynch. Western Gas Partners ( WES) rose 3.2% after Bank of America raised the stock's target price to $38 from $37. Other movers were Quicksilver Resources ( KWK), up 2.9%; Niska Gas Storage ( NKA), up 2.9%; Targa Resources ( NGLS), up 2.8%; and BreitBurn Energy ( BBEP), up 2.8%. Cabot Oil & Gas ( COG) advanced 2.2% after an analyst upgrade. Canaccord Genuity analyst John Gerdes raised the stock to buy from hold. KeyBanc Capital Markets raised its price target for Cabot from $64 to $85. Enbridge Energy Management ( EEQ), Energy Transfer Partners ( ETP) and Oneok Partners ( OKS) ended the week with gains of more than 2%. Solar stocks lagged last week. ReneSola lost 16%, while JA Solar Holdings wiped out 12.1% and Trina Solar relinquished 11%. Whiting Petroleum ( WLL) declined 10.3% as analyst Daniel Pratt of Ticonderoga Securities downgraded the stock to neutral from buy. Forest Oil ( FST) shed 9% last week following a downgrade. Susquehanna's analyst Duane Grubert lowered the stock's rating from positive to neutral with a 12-month target price of $32 per share. Other movers on the downside were Petrobras Argentina ( PZE), down 8.6%; GT Solar International ( SOLR), down 8.4%; RPC ( RES), down 8.3%; Provident Energy Trust ( PVX), down 8.2%; and Berry Petroleum ( BRY), down 7.6%. Tesoro ( TSO) fell 7.2%, while Nexen ( NXY) lost 7%.