A major part of the energy group at Washington-based law firm Dickstein Shapiro has joined Crowell & Moring, one of the District’s largest firms, as it looks to beef up its energy and environmental team as federal and state regulators mount a major push to create more renewable energy sources.

A trio of energy attorneys — partner Richard Lehfeldt and senior counsel Irving Yoskowitz in Washington, and counsel Laura Szabo in New York — announced their move to Crowell last week. The move comes on the heels of six other senior energy specialists leaving Dickstein for Crowell earlier this month: the group’s leader Larry Eisenstat, Patrick Lynch, Jonathan Odell, Patricia Alexander, Deborah Carpentier and Diana Jeschke, all in Washington.

The move brings together two important components of an energy and environmental practice — the group from Dickstein focused more on electricity, water and large infrastructure, while Crowell’s team specialized more in gas and environmental law, Lehfeldt said.

Energy and environmental lawyers advise on a range of work that deals with both regulatory law, such as setting rates for electricity, and corporate law, such as the buying and selling power plants.

A slew of recent and upcoming state and federal regulations governing emissions stands to make energy and environmental law a booming area for years to come. The U.S. Environmental Protection Agency is considering rules for greenhouse gas emissions, which could mean a glut of old power plants would have to be shut down — making way for new cleaner-burning plants to be built. And some states, like California, are setting ambitious targets to have a certain percentage of their electricity come from renewable sources like wind and solar energy.

“We believe the country is going to enter a serious wave of new development and construction in the power sector,” Lehfeldt said. “It’s necessary, and we think inevitable, and that’s what we do for a living.”