TransCanada Corp. sat atop the list of power companies in Canada and the U.S. in beating analyst estimates for first-quarter 2018 earnings.

The Calgary, Alberta-based company reported normalized earnings in U.S. dollars of 75 cents per share, beating the consensus estimate of 65 cents per share by 15.38%. The results for the quarter reflected the strong performance of TransCanada's legacy assets and growth projects, particularly its liquids pipeline business.

"We note C$7 billion of growth projects were placed into service over the last twelve months, which we see driving EPS expansion over the next year," CFRA Equity Research analysts said in a research note. CFRA has a "buy" recommendation on TransCanada shares.

Duke Energy Corp. came in second on the list, reporting earnings of $1.28 per share, compared with the S&P Capital IQ consensus normalized estimate of $1.14 per share.

UBS Investment Bank analyst Daniel Ford said Duke Energy is "off to a solid start" after handily exceeding expectations and also reiterating that no new equity is needed beyond $350 million per year.

"We've executed on the block equity trade and we'll continue with the [dividend reinvestment plan] and the [at-the-market programs], and we think that's the right amount of equity for us," said Duke Energy Executive Vice President and CFO Steven Young on equity needs to support the company's credit metrics.

PPL Corp. landed third after its first-quarter earnings benefited from strong results at its U.S. segments. PPL's earnings of 74 cents per share topped the consensus estimate of 66 cents per share.

But Macquarie Capital (USA) Inc. analysts remains bearish on PPL. The analysts reiterated their "underperform" rating on the company given a weak balance sheet, excessive dividend payout and a stepdown in U.K. earnings.

During the company's earnings call, executives again dismissed the idea of divesting its foreign business to raise equity and reduce exposure to unstable political and regulatory environment. "Divesting the U.K. [segment], either in part or whole, continues to be value destructive due to significant tax leakage and some other issues," said Chairman, President and CEO William Spence.

Meanwhile, Eversource Energy and FirstEnergy Corp. reported first-quarter earnings that were in line with analyst expectations. Earnings grew to 85 cents per share for Eversource Energy and to 67 cents per share for FirstEnergy.

California-headquartered utilities Sempra Energy, Edison International and PG&E Corp. occupied the last three spots of the list, after missing analyst estimates by 11.73%, 12.09% and 12.50%, respectively.

The first-quarter earnings calls of the these three utilities highlighted wildfire risks, as they pursue a comprehensive legislation to limit their liabilities and change the application of inverse condemnation in the state.