Yet moves to create a "smart" and more secure grid are still very much a work in progress, and come at a substantial cost. Regulated U.S. utilities already spent about $70 billion on capital expenditures in 2013, according to a recent study by Moody's Investor Service. Moves to sink money into an enhanced grid that can withstand unique 21st century-challenges may cause that price tag to swell.
"The electric utility industry is facing significant financial pressure as capital spending rises with requirements to upgrade aging infrastructure," said management consulting firm Deloitte & Touche in its 2013 outlook on power and utilities.
"Capital expenditures in the U.S. over the next 20 years are expected to cumulatively total well over $3 trillion," the firm added—with the bulk of that expected to be allocated to nonsecurity related initiatives.
While power companies have ramped up investments in the grid, observers say those efforts fall short of what's needed in the long term, especially since electricity regulation is fragmented across states.
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"The electric industry, largely motivated by the 2003 blackout, has undergone a huge effort to ensure the reliability of the electric grid," said Joel DeJesus, an attorney at Schiff Hardin and former official at the North American Electric Reliability Council, an industry group that focuses on regulatory policy.
"The industry is doing all it can do, but cybersecurity issues are constantly evolving," DeJesus said. "There is no 100 percent guarantee that [power] assets will be fully protected."
—By CNBC's Javier E. David