Written by Te-Ping Chen.

Here at the Washington Convention Center, the atmosphere most closely approximates that of a highly charged airport—that is, one milling with thousands of youth, thrumming with a steady, expectant hum.

It’s the first full day of Powershift 2009, and over 11,000 have descended on downtown DC’s largest venue for a weekend of training, rallying, and climate action lobbying.

More youth keep coming in waves, many with the attitude of embarking on a journey: full Nalgenes, sleeping bags, and stuffed backpacks. They crowd the cavernous halls, lying belly-flat on the geometric-patterned carpeting, pursing their lips over a schedule that spans some 200 events, chatting curiously.

Since the Energy Action Coalition last brought together youth like this in 2007, the gathering’s size as near-tripled, and the demands have likewise grown. A 40% reduction in emissions by 2020. A ban on coal. Immediate action–with climate legislation delivered and signed by the year’s end.

At last night’s keynote, the crowd greeted green activists like Majora Carter with a rock star’s welcome, while participating White House officials received roaring ovations. "You’re the same age the greatest generation was when they answered the call," EPA administrator Lisa Jackson told the crowd. "We need you."

Youth are representing all 50 states, as well as Canada, China and the United Kingdom, where organizers are planning a similar event later this year. Most are in college, with a smattering of high school youth. One group arrived at 7am after driving all night from Florida; others have taken 17-hour train rides across country to make the trip. At schools like Middlebury, nearly 10% of the student body is in attendance.

Amairani Galvan, a 15-year-old high school student from Chicago, says she’s here along with six friends to speak out against two local coal plants that damage her neighbors’ health.

"You don’t see power plants in rich neighborhoods," says Galvan. "We want to shut them down." On Monday, she’ll participate in one of 370 lobbying meetings the EAC has organized on Capitol Hill.

Greenpeace funded Galvan and her friends’ trip, while Powershift is subsidizing travel for another 1,500 youth. Dozens of youth I’ve met have been funded by their schools to come, and groups from SEIU to 1Sky to the Wal-Mart Foundation are supporting the event. (Others are also donating to offset participants’ travel carbon emissions.)

EAC executive director Jessy Tolkan calls the $1 million conference an "investment." "We want these youth go back to their communities and quadruple their power," she says. "It’s a global issue, and we need global action. These youth will be able to say they were here at the beginning."