Second-quarter earnings for S&P 500 members of the Zacks Utilities sector have been satisfactory so far. The sector is off to a solid start to the second-quarter earnings season, with NextEra Energy NEE and American Electric Power Company AEP beating estimates by 5.9% and 3.5%, respectively. For the quarter, the sector is expected to witness growth of 5.7% and 6.7% in earnings and revenues, respectively, per our latest Earnings Trends report.Utilities have been benefiting from new electric rates, customer additions, cost management, implementation of energy efficiency programs, ongoing investments to improve resilience of the electric infrastructure against extreme weather conditions and their transition toward cost-effective alternate sources of fuel to produce electricity.Factors to NoteUtilities across the United States have been making the most of economic improvement, as the nation continues to recover from the pandemic impact. Rollout of vaccines and increasing medical knowledge to deal with COVID-19 are gradually bringing life back to normal, despite threat from the new variant of the virus. Improving economic activities increased demand from the commercial and industrial (C&I) group in the second quarter. Stable demand from the residential space has been supporting the utilities.Utilities continued with their investments to strengthen transmission and distribution lines, expanded infrastructure, ensured proper maintenance of the existing infrastructure that aids in providing 24x7 services to customers as well as boosted earnings. The continuation of near-zero interest rates has been assisting capital-intensive companies to get funds at low costs to carry on with infrastructure strengthening work.Per the U.S. Energy Information Administration (“EIA”), electricity consumption in the United States will increase 2.8% in 2021, after falling 3.9% in 2020, primarily due to gradual improvement in economic conditions. The utilities are likely to have benefited from an increase in the demand for utility services in the second quarter driven by a boost in C&I activities. Per EIA, in 2021, electricity demand from industrial and commercial customers is likely to improve 5.1% and 2.1%, respectively, from 2020 levels.Let’s focus on a few utility companies that are scheduled to release second-quarter 2021 earnings on Jul 29.Xcel Energy XEL is slated to release quarterly results before the market opens. The company’s second-quarter results are expected to benefit from higher demand from increasing electric and natural gas customer volumes. New rates and cost management are likely to have acted as tailwinds. (Read more: What's in the Cards for Xcel Energy in Q2 Earnings?)Per the Zacks quantitative model, the combination of a positive Earnings ESP and a Zacks Rank #1 (Strong Buy), 2 (Buy) or 3 (Hold) increases the odds of an earnings beat. You can see the complete list of today’s Zacks #1 Rank stocks here.Our proven model predicts an earnings beat for Xcel Energy this time around. It has an Earnings ESP of +0.45% and a Zacks Rank of 3. You can uncover the best stocks to buy or sell before they're reported with our Earnings ESP Filter.Xcel Energy Inc. Price and EPS Surprise Xcel Energy Inc. price-eps-surprise | Xcel Energy Inc. QuoteThe Southern Company SO is set to release quarterly results before market open. Second-quarter earnings are likely to have benefited from its expanding customer base. Yet, rising operating costs may have been a concern. (Read more: Southern Company Queued for Q2 Earnings: Things to Note)The company currently has an Earnings ESP of 0.00% and a Zacks Rank of 3.Southern Company The Price and EPS Surprise Southern Company The price-eps-surprise | Southern Company The QuoteEdison International EIX is scheduled to report quarterly results after market close. Second-quarter earnings are likely to have benefited from above-average temperatures, which must have spurred electricity demand among the utility’s customers in the region. (Read more: What's in Store for Edison International in Q2 Earnings?)The company currently has an Earnings ESP of -1.66% and a Zacks Rank of 3.Edison International Price and EPS Surprise Edison International price-eps-surprise | Edison International QuoteCMS Energy CMS is set to release quarterly results before market open. Improving economic activities in its service territories are likely to have boosted demand in the second quarter from all customer groups. (Read more: CMS Energy to Report Q2 Earnings: What's in the Cards?)The company currently has an Earnings ESP of + 4.17% and a Zacks Rank of 4 (Sell).CMS Energy Corporation Price and EPS Surprise CMS Energy Corporation price-eps-surprise | CMS Energy Corporation QuoteEversource Energy ES is slated to release quarterly results before the market opens. The company’s second-quarter results are expected to benefit from contribution from the acquired Columbia Gas of Massachusetts assets. Its second-quarter earnings are likely to have benefited from electric transmission system investment. (Read more: Eversource Energy to Post Q2 Earnings: What's in Store?)The company currently has an Earnings ESP of -0.06% and a Zacks Rank of 4.Eversource Energy Price and EPS Surprise Eversource Energy price-eps-surprise | Eversource Energy Quote Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. You know this company from its past glory days, but few would expect that it's poised for a monster turnaround. Fresh from a successful repositioning and flush with A-list celeb endorsements, it could rival or surpass other recent Zacks' Stocks Set to Double like Boston Beer Company which shot up +143.0% in a little more than 9 months and Nvidia which boomed +175.9% in one year.Free: See Our Top Stock and 4 Runners Up >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Xcel Energy Inc. (XEL): Free Stock Analysis Report NextEra Energy, Inc. (NEE): Free Stock Analysis Report Southern Company The (SO): Free Stock Analysis Report Edison International (EIX): Free Stock Analysis Report American Electric Power Company, Inc. (AEP): Free Stock Analysis Report CMS Energy Corporation (CMS): Free Stock Analysis Report Eversource Energy (ES): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research