Author and environmental activist Bill McKibben and his merry band of modern-day pranksters didn't get President Obama to put solar on the White House after all.

"Somber meeting at the @WhiteHouse," McKibben said in a tweet after this morning's meeting. "They don't want the panel, will continue 'deliberative process' re the roof. On we go!"

The crew drove from Unity College in Maine with a vintage solar panel that President Jimmy Carter installed during his presidency. It was removed by a subsequent administration, and that's how Unity got ahold of it.

Part of the mission was to promote Oct. 10, or 10/10/10, an effort launched by McKibben and students to stage a global work day in which teams pursue clean energy projects across the globe. 350.org is the website coordinating various projects.

The solar panel will not return to Maine.

"As for now, the Carter panel will stay in D.C., a symbol of a road not taken, yesterday and today," said a post on putsolaron.it. "The fantastic Unity College crew will head back up to Maine and start classes for the semester. And Bill McKibben will head home for a few days of rest, before hitting the road again to promote 10/10/10."