Exelon (NYSE:EXC) reported earnings yesterday, beating top-line estimates, but just missing the mark on profit. With plummeting power prices, and a rapidly changing energy world, investors need to know if Exelon can still cut it in quarters to come. Here's what you need to know.

Number crunching
Exelon's Q2 sales clocked in at $5.88 billion, a solid $120 million above Mr. Market's estimates for the utility. With GAAP earnings up a seasonally adjusted 3.1%, it seems that the utility's merger with Constellation Energy last year might finally be paying off.

But even as Exelon expanded its top line, the company missed slightly on bottom-line estimates. Adjusted EPS clocked in at $0.53, $0.01 below analyst estimates, and 13% below Q2 2012's Non-GAAP EPS.

Looking back over the past five years, sales have increased 31.5%, while adjusted EPS has tumbled 72% (with nearly 100% of the profit drop occurring in the last year).

EXC Revenue TTM data by YCharts 

Exelon stock fell 2.8% yesterday, which was most likely due to the realization that low power prices are having a significant effect on this utility's earnings. Around 65% of Exelon's generation fleet relies on PJM auctions, and its coal markets took a major hit last quarter. The utility announced additional $350 million and $400 million reductions off its 2014 and 2015 sales as electricity stays cheap. While prices are out of the utility's control, diversification of risk is an important element to consider.

Another big question moving forward is whether Exelon can continue to cut costs as its squeezes economies of scale out of its Constellation merger. According to its latest report, Exelon is on track to snag $550 million in synergy savings by 2014, and expects to keep saving that same amount annually.

Investors should also look to Duke Energy's (NYSE:DUK) upcoming earnings to decide whether its Progress Energy partnership is paying off. The deal theoretically boosted Duke's assets 56%, and revenue 79%, but diminished demand has put a cramp on utilities' "bigger is better" philosophy.

At 3.9%, Exelon's dividend is an attraction for most income investors. The company recently cut its distribution 40%, clearing up capital to invest and grow elsewhere, "even when prices move against us," noted CEO Chris Cane during the earnings call. Shareholders shouldn't be worried about another cut anytime soon, but pure dividend investors with low risk tolerance should take a look at some other players, as well. With a 4.7% annual yield, PPL's (NYSE:PPL) British-American split gives it geographic diversity, and it continues to set itself up for smooth regulatory waters, with a recently submitted eight-year power plan.

Can Exelon excel?
Exelon stock came out swinging at the start of 2013, rising around 30%. Year to date, shares now stand a paltry 2.9% higher, double digits below the S&P 500's (SNPINDEX:^GSPC) 18.2% gain.

EXC data by YCharts 

But now more than ever before, tough times ahead are built in to Exelon stock prices. With a solid dividend and stable business model, Exelon stock remains a value buy for any income investor. If this quarter is any evidence, rocky power prices will affect this nuclear-centric deregulated utility more than many of its competitors -- but for those patient enough to wait, an (eventual) economic recovery could reward Exelon stock investors handsomely.