There's a broadening consensus that a hefty chunk of whatever Congress is planning to spend on an economic-stimulus package should go toward infrastructure. Ideally that would mean "green" projects like efficiency upgrades or transit, rather than just building more highways (though it's certainly worth fixing up existing roads and bridges). Obama's certainly thinking along these lines; as he explained to Rachel Maddow the other day, Congress should focus on updating the nation's electrical grid. But why would we want to do a thing like that? Over at Good's website, Ben Jervey has written a "dummy's guide to the 'smart grid'" that's as good a short intro as you'll find on this subject:

Last month I listened to a panel of energy experts explain to the New York City Council’s Infrastructure Task Force that Gotham’s grid simply couldn’t handle a proposed new supply of electricity flowing in from rooftop solar and offshore wind. Why? Because our current grid is dumb and wildly inefficient.

A blind system of transmission lines and converters, today’s grid funnels electricity one-way—from big centralized power plants to our factories, streetlights, shops, and homes. The utilities can’t detect fluctuations in energy demand; so, to ensure there are no shortages, the power plants run at full tilt, burning greenhouse gas-emitting fossil fuels around the clock. Not to mention, there is a lot of juice lost from coal-fired plant to the socket–5 to 10 percent due to “line loss” in the transmission wires alone. It’s also dreadfully vulnerable to disruptions, whether a break in the system—like a heavy branch taking down a roadside line—or an influx of power from an unexpected source. That’s bad news anyone who wants to plug his solar panels and sell electricity back to the grid.

The Internet of electricity—Al Gore coined the term “electranet” in an op-ed for Newsweek a couple years back—a smart grid would be networks, microprocessors and digital sensing technologies, a “web” of clever, hi-tech components that will be as flexible as it is intelligent. (The Wall Street Journal recently drew up a handy interactive model of such a system.) Supercomputers will let the utilities predict and manage system-wide demand and capacity, with batteries and other storage mechanisms ensuring that there’s always enough power to handle consumers’ needs.

Power from distributed carbon-free sources such as rooftop solar, wind turbines, and combined heat and power systems will feed into the grid without causing breakdowns, so customers will be able to buy electricity for their homes and businesses, as well as sell power they generate back. “Smart meters” in buildings and homes will show the real-time cost of energy and assure that those that energy contributed to the grid—whether from a suburban family with photovoltaic panels on its roof or a Great Plains rancher with a wind turbine—receive payment. These distributed energy sources will require power to travel less distance, eliminating some electricity waste or “line loss.” Finally, internal building controls will adjust power demand, and new substations will take feedback from sensors along the transmission lines to better route electricity flow.

Okay, but how about a price tag? The Energy Department says it would cost the equivalent of "one medium pizza per household per month, spread over 10 to 15 years," though a modernized grid would also save the country "tens of billions of dollars" each year through "reduced interruptions, reduced congestion and reduced need to build expensive plants and lines." (Among other things, a smart grid that managed demand wisely would allow us to shutter a number of the country's "peaking plants"—usually inefficient, expensive, dirty gas turbines—that run just a few hours each year, for those rare times when demand goes through the roof. About 14 percent of the country's 2,600 power plants basically just sit around for this purpose.)

We'll also, as both Obama and Jervey note, need a smart grid to accommodate a future full of electric cars and plug-ins—the cars would essentially act as a distributed storage system, powering up during the night, when, say, wind turbines are spinning but no one needs the electricity. Not a bad investment all around—and precisely the sort of project that calls for federal action, since, as The New York Times reported recently, many state governments don't want to invest in grid upgrades that would only benefit, say, wind farms in neighboring state. (Of course, states also tend to jealously protect their authority over their local grids, so this will require more than just money.)

--Bradford Plumer