WARWICK — The state’s first-ever interfaith conference on what religious communities can do to save the earth’s resources and prevent global warming drew a larger-than-expected crowd of clergy, educators and lay leaders to Bishop Hendricken High School Thursday in what some saw as a sign of the increased attention houses of worship are giving to environmental concerns.

Howie Brown, director of New England Power and Light, which was formed a year ago as an interfaith response to what some see as a coming ecological crisis, said organizers had not expected the standing-room-only crowd of more than 150 and that the spectrum would be so diverse, with participation by Protestants, Jews, Catholics, Greek Orthodox Christians, Mormons and Baha’is.

Some of the participants were drawn to the event by the reputation of the keynote speaker, the Rev. Margaret Bullitt-Jonas, an Episcopal priest from Amherst, Mass., who is part of Religious Witnesses for the Earth. But others were drawn by the workshops, including one featuring lay leaders talking about conservation in their congregations and efforts to get more people in the pews to “think green.”

In her keynote, Bullitt-Jonas said she didn’t think she had to go into detail about the effects of global warming. “You know that the scientific debate about the reality of global warming is over. You know that the world’s leading scientists agree that if we keep burning fossil fuels at the present rate, global warming caused by human activities could raise worldwide average temperatures between 5 and 11 degrees within this century.”

Faced with that sort of unprecedented challenge, raising the possibility that “conscious life on this planet may not survive,” she declared, “we need to root ourselves in the deep wisdom of our respective faith traditions and come together to discover how we can work together to protect this one planet, one sky, that we all share.”

In a workshop on “Cool Congregations,” Barney Heath, a member of the social action committee at Temple Emanu-El, in Providence, said it is not always easy convincing boards of congregations to adopt conservation recommendations, especially if they don’t see any immediate financial payoff.

But he said his congregation has come a long way. The temple has implemented all the recommendations that came from a RISE energy audit and has already begun to see savings. And to cut the use of plastic, the temple’s caterer has invested in 500 permanent plates.

Amy Tully and Katherine Gibson, members of the Green Team at St. Augustine’s Episcopal parish, on the campus of the University of Rhode Island, said that in trying to move a congregation, it is always helpful to start with something “small and visible,” such as converting to compact fluorescent light bulbs, and then later nudge them toward other steps, such as cutting down on heat and air conditioning.

But the two said the road has not always been easy. Said Tully: “We’re still struggling with Styrofoam at coffee hours because no one wants to stay late enough to wash the cups.”

And, they said, the overhead fans that had been installed as a conservation measure have drawn complaints from altar servers, who say the fans make the candles burn faster, causing wax to fall on the linens.

Beth Milhame, whose church, Channing Memorial Unitarian, in Newport, organized a community showing of Al Gore’s film, An Inconvenient Truth, said her church may have solved the cleaning problem by introducing plates made from potato and sugar. They’ll learn soon enough whether they decompose.

rdujardi@projo.com