Steven Chu has left the building

At the DOE, the Nobel Prize-winning physicist oversaw expanded federal support for low-carbon energy, and defended it against GOP attacks when some of the efforts stumbled.

Chu announced his intention to leave the DOE in early February. Click here for more E2-Wire coverage of Chu’s sometimes rocky tenure at the department.

He was the longest-serving secretary in DOE history.

Deputy Energy Secretary Daniel Poneman has stepped into Chu’s shoes on an acting basis while senators get around to confirming Ernest MonizErnest MonizOvernight Energy: Trump signs climate order | Greens vow to fight back What we learned from Rick Perry's confirmation hearing Overnight Energy: Rough hearing for Tillerson MORE, the nominee to replace Chu.

Moniz, a Massachusetts Institute of Technology physicist, is likely to win full Senate approval soon after sailing through the Energy and Natural Resources Committee in a bipartisan 21-1 vote last week.

Poneman’s first day as acting secretary will include a Capitol Hill event with the directors of DOE’s various “Energy Innovation Hubs” that were established under Chu. Rep. Chaka Fattah (D-Pa.) is hosting the event.

The department put together a retrospective of Chu’s tenure here.