The work was financed by millions of ordinary ratepayers. Steven R. Herling, a senior official at PJM Interconnection, a regional authority for the grid, said the need to feed the mushrooming data centers in Northern Virginia was the “tipping point” for the project in an otherwise down economy.

Data centers in the area now consume almost 500 million watts of electricity, said Jim Norvelle, a spokesman for Dominion Virginia Power, the major utility there. Dominion estimates that the load could rise to more than a billion watts over the next five years.

Data centers are among utilities’ most prized customers. Many utilities around the country recruit the facilities for their almost unvarying round-the-clock loads. Large, steady consumption is profitable for utilities because it allows them to plan their own power purchases in advance and market their services at night, when demand by other customers plummets.

Mr. Bramfitt, the former utility executive, said he feared that this dynamic was encouraging a wasteful industry to cling to its pedal-to-the-metal habits. Even with all the energy and hardware pouring into the field, others believe it will be a challenge for current methods of storing and processing data to keep up with the digital tsunami.

Some industry experts believe a solution lies in the cloud: centralizing computing among large and well-operated data centers. Those data centers would rely heavily on a technology called virtualization, which in effect allows servers to merge their identities into large, flexible computing resources that can be doled out as needed to users, wherever they are.

One advocate of that approach is Mr. Koomey, the Stanford data center expert. But he said that many companies that try to manage their own data centers, either in-house or in rental spaces, are still unfamiliar with or distrustful of the new cloud technology. Unfortunately, those companies account for the great majority of energy usage by data centers, Mr. Koomey said.

Others express deep skepticism of the cloud, saying that the sometimes mystical-sounding belief in its possibilities is belied by the physicality of the infrastructure needed to support it.