HARTFORD >> U.S. Energy Secretary Ernest Moniz used a whirlwind trip to southern New England to voice his support for efforts to end capacity problems with natural gas transmission lines in New England.

Moniz visited Providence Monday morning and came to the Connecticut Department of Energy and Environmental Protection headquarters in the afternoon as energy industry officials discussed the need to bring more natural gas into the region. The two events were part of the federal agency’s Quadrennial Energy Review.

Moniz was joined by Gov. Dannel P. Malloy, as well as Connecticut’s U.S. Reps. John Larson, D-1, and Elizabeth Esty, D-5.

Moniz and other participants at the forum agreed that coming up with a solution to the lack of capacity in natural gas transmission lines will require a delicate balancing act. That’s because New England relies heavily on natural gas not only to heat homes, but also to run the region’s power plants which provide electricity.

But forum participants disagreed widely over the best way to address the problem.

Malloy has cast Connecticut’s lot with those who believe a large-scale expansion of the natural gas transmission network is in order. At end of last year, he joined with the five other governors in the region to call for expanding the natural gas infrastructure.

Katie Dykes, DEEP’s deputy commissioner in charge of energy, told participants in the forum that representatives of the six states “have been working very hard” since then to allocate the costs of a pipeline expansion between ratepayers across the region.

Other participants said such a broad-based expansion plan fails to take into account the ability of middle-class ratepayers to afford such infrastructure upgrades. They urged an approach that is less focused on pipeline expansion and more on use of existing liquefied natural gas supplies and energy conservation.

“We would strongly encourage DOE to take whatever steps it can to ensure that the region looks to innovative energy solutions that are the lowest-cost, most consumer-friendly, and climate-safe,” William Dornbos, Connecticut director for the group Environment Northeast, said. “Supply constraints do not always have to be solved through major capital investments in expensive physical infrastructure like interstate natural gas pipelines or electric transmission lines. Smarter energy management — using the energy resources we already have more efficiently and more flexibly — can also provide solutions to electric and natural gas supply issues.”

But Gordon van Welie, president and chief executive officer of ISO-New England, said the reliability of the electric power grid “would face dire consequences” if there was a short-term interruption in the ability to get natural gas from the existing transmission lines or if the region were temporarily unable to get power generated from its nuclear power plants.