Charleston City Council's resolution about shoreside power for cruise ships isn't as definitive as most advocates have demanded. Installation is not yet on the horizon.

But the resolution passed Tuesday reflects a small step in the right direction, and a major change in the conversation regarding the subject.

A few years ago, shoreside power for cruise ships at the port of Charleston wasn't even on the State Ports Authority's agenda. Officials had concluded it was too expensive, and their focus was on building a new terminal.

Judging from Tuesday's council meeting, air quality issues related to cruise ships will no longer be an after-thought.

SPA President and CEO Jim Newsome said the new terminal will have shoreside power capabilities if needed.

A bill in the Legislature would provide $5 million toward the installation.

And City Council, which previously has shunned opportunities to regulate the cruise ship industry, agreed by a 10-2 margin to support shoreside power "as and when needed."

At present, cruise ships - Carnival's Fantasy in particular - run a diesel engine the entire time they are at dock in order to power on-board systems like air-conditioning. Neighbors, physicians and environmentalists have complained about soot and harmful toxins emitted because of that practice, and rallied to push the SPA to install shoreside power so cruise ships can plug into the electrical grid while docked.

The SPA is satisfied with Carnival's plans to add scrubbers to the Fantasy. The feds have agreed to let the cruise line use them on some ships instead of upgrading to cleaner fuel now required of cruise ships. Scrubbers are designed to reduce sulfur dioxide and trap soot.

But shore power is far more effective at reducing air pollution for ships at berth.

Indeed, the Cruise Line Industry Association says it is "working with ports and local governments to reduce waste and emissions by implementing shoreside electrical power to eliminate engine emissions while in port. Currently, this infrastructure is available at approximately a dozen berths in North America, and we strongly support extending it to other ports."

The initial resolution was put on the agenda by Councilman Dudley Gregorie, who has been a proponent of shoreside power, and amended by Mayor Joe Riley to affirm what the SPA and Carnival already are doing and give the SPA time to study the matter as it readies plans for a new terminal.

It is nevertheless encouraging that Council showed an open mind toward shore power, and that dialogue on the subject was productive, even if the final product leaves a lot of room for the SPA to sidestep the issue.

At least residents and people who work at or near the port have assurance that cruise ship air emissions will be studied and addressed. Since the debate began two years ago, it's become increasingly clear that shoreside power is the superior option for this historic city.

Expect the pressure to continue for its installation.