Stocks traded in a narrow range on paper-thin volume Friday as Wall Street slowly regrouped after the largest electrical blackout in North American history.

The blue-chip Dow Jones industrial average (search) ended up 11.13 points, or 0.12 percent, at 9,321.69. The broader Standard & Poor's 500 Index (search) gained 0.17 of a point, or 0.02 percent, to 990.68. The technology-laced Nasdaq Composite Index (search) rose 1.66 points, or 0.10 percent, to finish at 1,702.00.

For the week, the Dow rose 1.42 percent, the S&P 500 gained 1.34 percent, and the Nasdaq advanced 3.53 percent.

Just 699.2 million shares traded on the Nasdaq, making it the lightest trading day so far this year. Volume was also extremely light on the New York Stock Exchange, with just 562.6 million shares changing hands, compared with an average daily volume of 1.45 billion.

The New York Stock Exchange and the Nasdaq opened normally at 9:30 a.m. EDT but the smaller American Stock Exchange (search) only managed to open for trade at 3:45 p.m. after a delay caused by problems with its air conditioning. The exchange took orders until 4:15 p.m.

Meanwhile, the Bond Market Association recommended an early close at 2 p.m. to give traders more time to get home. In coordination, the Chicago Mercantile Exchange ended trading by open outcry on interest rate futures at 2:15 p.m.

The blackout, which also affected other parts of the Northeast and southern Canada, started at 4:11 p.m. Thursday, soon after stock trading ended for the day. Parts of New York and its suburbs were still without electricity on Friday.

"Thank you, everybody, for making the effort to come in today," New York City mayor Michael Bloomberg told traders on the floor when he rang the opening bell at the NYSE.

NYSE Chairman Richard Grasso said he and other top executives stayed at the NYSE building in lower Manhattan overnight, along with 300 other NYSE traders and employees.

"It's very, very quiet. Virtually nothing's going on," said Tim Smalls, managing director at S.G. Cowen.

"We're one of the few lucky firms, and got our senior personnel in. But there are firms that are shut down and not operating. Everyone's running on a skeletal staff today," Smalls said.

Friday marked the expiration of August individual equity options and some stock-index options, which often leads to additional volatility in stock prices and the market.

"Normally you'd see a lot more volatility, since we also have options expiry today. But there's so many connectivity problems, most people decided to watch and wait instead of be actively trading today," said Jeff Swensen, a senior trader at John Hancock Advisers.

On the Nasdaq, shares of alternative energy companies posted some of the largest gains in the wake of the blackout.

Shares of American Superconductor Corp.(AMSC), which makes superconductor cables, jumped $3.95, or 42.64 percent, to $13.20. It was among the Nasdaq's most actively traded shares and the Nasdaq's No. 2 percentage gainer. Scientists hope such cables can pack more power on less wire, unclogging congested power grids.

Shares of American Power Conversion Corp.(APCC), which makes power protection systems, surged 11.26 percent, or $1.82, to $17.98. This stock also ranked among the Nasdaq's most active names.

Dell Inc. (DELL) rose, a day after the No. 1 personal computer company reported its fifth straight quarter of year-on-year profit improvement and said technology demand has stabilized, though not greatly improved. Dell shares added 95 cents, or 3.03 percent, to $32.34.

Kohl's Corp. (KSS) climbed $2.50, or 4.1 percent, to $63.54. The retailer reported its second-quarter earnings fell nearly 10 percent, hurt by rainy weather and an inventory bulge. But it still managed to beat its lowered estimates, and backed analysts' earnings estimates for the current quarter.

Protein Design Labs Inc. (PDLI) sank $3.77, or 26 percent, to $10.72. The company said it believes Genentech Inc. should pay it licensing fees for technology related to Genentech's new asthma drug Xolair, a potential major revenue generator, but Genentech does not agree.

The Consumer Price Index (search), the most widely used gauge of U.S. inflation, rose 0.2 percent in July, the same as in June, with energy prices up a solid 0.4 percent, the Labor Department said.

The University of Michigan (search) said it was delaying the release of its preliminary reading of August consumer sentiment until Tuesday, due to the blackout. The University of Michigan had been scheduled to release its index of consumer sentiment at 9:45 a.m.

A report shortly after the open showed that U.S. industrial output in July posted its biggest gain since January, boosted by a big gain in utilities output and a third straight monthly rise in factory activity.

The Russell 2000 index, which tracks smaller company stocks, closed up 0.70, or 0.2 percent, at 471.92.

Overseas, Japan's Nikkei stock average fell 0.5 percent. In afternoon trading in Europe, France's CAC-40 was up 0.5 percent, Britain's FTSE 100 rose 0.2 percent and Germany's DAX index fell 0.3 percent.

Reuters and the Associated Press contributed to this report.