It’s not your father’s Senate Energy panel anymore.

With former Chairman Pete Domenici (R-N.M.) retired and its jurisdictional issues driving the national debate, the Energy and Natural Resources Committee is going through rapid changes, lobbyists say, requiring a new approach to its leadership and a command of complex industries far beyond the traditional sectors.

“It’s no longer just a one or two calculus equation — it’s a four or five variable equation— one energy lobbyist observed. “We’re no longer just measuring the oil sector and the price of gas.—

Although the panel is still dominated by lawmakers from sparsely populated but resource-rich states such as New Mexico and Alaska, lobbyists say Chairman Jeff Bingaman’s (D-N.M.) consensus-style management and wonky nature continue to keep lobbyists guessing.

Hired guns also say Bingaman, who assumed the committee’s gavel most recently last Congress, is also stressing environmental and consumer considerations in legislation, a far cry perhaps from the panel’s former “parochial— approach.

Scott Segal, a partner at Bracewell & Giuliani, said his job now entails “finding common ground between the producer and the consumer of energy.— He added that Domenici was a “traditionalist,— whereas Bingaman “has always been a little more laid-back,— more prone to building alliances than the “Old Bull— Domenici.

“In the last several years, there’s been a lot more concentration on the need to develop new and innovative ways to approach energy policy — and that’s on a national platform,— Segal said. “As energy policy has become a national concern, the ability to frame arguments that reflect both difficulty in producing energy as well as the effects on price and supply.—

He added: “Twenty-five years ago, you might have said, This is why producers need x, y or z.’—

Despite changes at the top, Segal also said both parties continue to work well together on the panel, typically setting aside partisan differences for the sake of the powerful interests back home. Members and staff alike, he said, tend to be well-versed in the panel’s arcane subject matter and just “want to get stuff done.—

“It’s definitely a committee that values substantive expertise … oftentimes Senators that serve on that committee have a regional affinity for the issue that they’re dealing with,— Segal said, adding that “the committee has a very workable relationship between the Democratic and Republican sides.—

“The issues are more regional than partisan,— he said.

The committee’s roster includes ranking member Lisa Murkowski (R-Alaska) and Sens. Byron Dorgan (D-N.D.), Tim Johnson (D-S.D.), John Barrasso (R-Wyo.), Sam Brownback (R-Kan.) and James Risch (R-Idaho).

Jonathan Jones, a partner at Peck, Madigan, Jones & Stewart, said the panel’s staff “is quite accessible,— adding that they, too, are keeping up with the steep learning curve that new Democratic priorities require.

The staff has “become just as knowledgeable on the renewable issues, which have become more national issues,— Jones said. “I have always found that they’re able to sit down and work out a solution for you.—

But Bingaman is not without his critics. His relaxed attitude — staffers are said to call him “Jeff— rather than “Senator— — and academic tendencies make him hard to read, complicating the handicapping process for clients. Even more, a handshake with the Senate Energy chairman may not mean what it used to.

“Bingaman seems to be more focused on the deal than what needs to be done — he’ll say one thing but then [later] it will seem like he never said them,— an energy lobbyist said. “Domenici would make a concession and then try to work around the concession. Bingaman will make a concession and then walk away from it.—