Cruise ships docked in Charleston soon could be plugging into a shoreside power outlet, a welcome development for groups that have complained about fumes from the idling vessels.

State Reps. Jim Merrill and Leon Stavrinakis announced a plan Friday to authorize up to $5 million to install the necessary equipment at the State Ports Authority passenger terminal at Union Pier.

Merrill, R-Charleston, and Stavrinakis, D-Charleston, both serve on the House Ways and Means Committee. They expect their proposal to be included in this year’s budget.

“With this new technology, Charleston will be a national leader in both economic growth and environmental innovation,” Stavrinakis said in a statement. “Shoreside power will ultimately bring more tourism dollars to Charleston while cleaning up our air at the same time.”

Shoreside power has been mentioned as one way to bring together the feuding sides in a long-running dispute about the future of the cruise industry in Charleston.

Merrill said the shoreside power could ease the tensions.

“It definitely should take away one concern that is expressed, and what we want to do is find a solution,” he said. “We see the ports authority’s position of requiring shore power on every ship puts them at an economical disadvantage, and it doesn’t work on all ships, but for those that have it, this gives them the option.”

The SPA applauded the efforts by Merrill and Stavrinakis on Friday, but it stopped short of fully endorsing shoreside power for cruise ships.

“While we understand that shoreside power has been the focus of conversations to date, the industry is also pursuing other more modern technologies that provide equal or greater benefits,” the maritime agency said in a statement. “We anticipate utilizing the industry’s most modern and efficient technologies at the new passenger terminal at Union Pier and applying these proposed funds, if appropriated, to implement these practices.”

Environmentalists and neighborhood groups have complained about pollution in the historic district coming from cruise ships idling their engines at Union Pier. Most complaints target the Carnival Fantasy, which is based in Charleston year round.

On Friday, the groups said they support what the lawmakers are proposing.

“We commend this effort for attempting to address the serious health and environmental effects of cruise ship diesel soot, and hope efforts are made to explore the other means of reducing cruise impacts on the historic peninsula,” said Carrie Agnew, executive director of the Charleston Communities for Cruise Control. “We have always and continue to support shore power at the new terminal, wherever it is ultimately built.”

Dana Beach, executive director of the Coastal Conservation League, said it would be “a huge step forward.”

“We have said consistently that shore-side power is the only way we can completely protect the health of residents from the emissions from cruise ships,” Beach said Friday.

Last year, his Charleston-based group released a study that concluded hooking a cruise ship to shoreside power source would cut toxic emissions by 19 percent to 90 percent, depending on the type of fuel the vessel burns.

The SPA took a close look at shoreside power while planning a new $35 million cruise terminal it wants to open at Union Pier. It concluded it was too costly.

In 2011, the SPA estimated it would have invest $5.6 million to provide shoreside power,. Carnival Cruise Lines would have to spend about another $1.5 million to retrofit the Fantasy, the cruise ship that calls on Charleston most often.

The SPA wants to redevelop a warehouse at the north end of Union Pier to replace its current cruise terminal at the south end of the terminal. The new building could handle larger ships and more passengers.

Lawsuits have stalled those plans.

In addition to shoreside power, groups like Charleston Communities for Cruise Control and the Coastal Conservation League have argued for limits on ship visits and passengers.