The following energy companies were mentioned by analysts during the week of September 24 to 30. This information, to be used for the purpose of evaluating potential investments, was distilled from a daily list of analyst upgrades, downgrades and initiations compiled byaAnalyst Ratings Network.Evolution Petroleum Corp.a (NYSE:EPM) acquires and develops properties that produce oil and natural gas in the US, with total proven reserves of 12,768 million barrels of oil equivalent. Evolution Petroleum posted record recurring results for 2013, announcing in September that full-year revenues increased 19 percent and earnings per share were up 36 percent. Evolution Petroleum isanow covered by analysts at Northland Capital Partners. They set an "outperform" rating and a $14.50 price target on the stock. 28.4 percent upside. Laredo Petroleum Holdings Inc.a (NYSE:LPI) is focused on oil and natural gas exploration in the Permian region of the United States. In May 2013 Laredo sold its assets in the Anadarko Basin to EnerVest for $438 million. Lardo Petroleum Holdings isanow covered by analysts at Northland Capital Partners. They set an "outperform" rating and a $36.00 price target on the stock. 22.0 percent upside. Patterson-UTI Energy Inc.a (NASDAQ:PTEN) and its subsidiaries have over 300 land-based drilling rigs in the United States and Canada.aPatterson-UTI Energy is now covered by analysts at Bank of America Corp.. They set a "buy" rating and a $27.00 price target on the stock. 23.7 percent upside. Diamond Offshore Drilling Inc.a (NYSE:DO) has a fleet of offshore drilling rigs consisting of 30 semisubmersibles, 7 jack-ups and one drillship. Earlier this year Diamond Offshore Drilling announced anaagreementawith Hyundai Heavy Industries Co, Ltd. (KRX:009540) to build a new submersible drilling rig for approximately $755 million. The company was upgraded by analysts at Guggenheim from a "neutral" rating to a "buy" rating. They now have an $80.00 price target on the stock, up previously from $73.00. 28.8 percent upside. Consol Energy Inc.a (NYSE:CNX) is the leading energy producer in the Appalachian Basin of the United States, Consol Energy says on its website. The company produces both natural gas and high-BTU coal. Consol Energyawas upgraded by analysts at Goldman Sachs Group Inc. from a "neutral" rating to a "buy" rating. They now have a $43.00 price target on the stock, up previously from $35.00. 27.3 percent upside. China Petroleum and ChemicalaCorp (Sinopec) (NYSE:SNP)ais a Chinese state-owned petroleum and petrochemicals group. It is the fifth largest company in the world by revenue. In August of this year Sinopec purchased a US$3.1 billion stake in an Egyptian oil and gas operation from US-based Apache Corp. (NYSE:APA). Sinopec was upgraded by analysts at Zacks from an "underperform" rating to an "outperform" rating. They now have a $96.00 price target on the stock. 20.5 percent upside. Trilogy Energya (TSX:TET) is focused on tight gas reservoirs where horizontal drilling technology can be used to add low-cost reserves and grow production. In the first quarter of 2013, Trilogy averaged 36,110 barrels of oil a day (boed), with liquids comprising 46 percent of the total. Its 2013 guidance is 40,000 to 42,000 boed. aTrilogy Energyawas upgraded by analysts at RBC Capital from a "sector perform" rating to an "outperform" rating. They now have a C$33.00 price target on the stock. 27.2 percent upside. Miller Energy Resources Inc.a (NYSE:MILL) is a natural gas exploration and production company, focused on the Cook Inlet of Alaska and the Appalachian Basin. Miller Energy Resources has proven oil reserves of 8.61 million barrels of oil equivalent. The companyais now covered by analysts at Imperial Capital. They set an "outperform" rating and a $9.50 price target on the stock. 32.7 percent upside. Marathon Oil Corp.a(NYSE:MRO) is involved in exploration, production, oil sands and integrated gas operations in the US, Canada, Africa, the Middle East, Norway, Poland and the UK.aMarathon Oil Corpawas upgraded by analysts at Argus from a "hold" rating to a "buy" rating. They now have a $42.00 price target on the stock, up previously from $34.90. 20.3 percent upside. Paramount Resourcesa (TSX:POU) explores for, develops and transports petroleum and natural gas. It hasafour operating units: the Kaybob region of Alberta; Grand Prairie; the Northern area including Northwest Alberta, the Northwest Territories and Northeast British Columbia; and the Southern area which includes production from southern Alberta. Paramount Resourcesawas upgraded by analysts at Scotiabank from a "sector perform" rating to an "outperform" rating. They now have a C$45.00 price target on the stock. 30.4 percent upside.