A Hawaiian Electric Co. executive said the utility is considering offshore resources to get Oahu to 100 percent renewable energy use because the island can’t achieve the goal with the space it has.

Colton Ching, vice president of energy delivery at HECO, made the point at a meeting Tuesday with energy experts on the utility’s 30-year power plan. Building an offshore wind farm and a transmission line that would connect the renewable energy resources of neighbor islands with Oahu were two options HECO said it wants to consider in its renewable road map.

Ching said the utility will offer a more detailed analysis of the options in August when HECO files its final version of a 30-year power plan for the electrical utilities serving Oahu, Hawaii island and Maui County.

Plans for a cable to connect Oahu’s power grid to neighbor islands were met with opposition previously. Gerald Sumida, an attorney for Carlsmith Ball LLP who attended the Tuesday meeting, said HECO should consider the community response to the interisland power cable.

“I just raise the consideration that comes from immense criticism that other islands are being used to serve the purpose of Oahu, that raises substantial political implications,” Sumida said.

A 2009 proposal to build wind farms on Lanai and Molokai and send power to Oahu via a one-way cable was seen by some as Oahu tapping other islands for more energy. A 2013 proposal for a two-way transmission cable, which would link Maui and Oahu, hasn’t moved forward, but is still alive within the PUC.

Kyle Datta, general partner at Ulupono Initiative, questioned HECO’s assumption that Oahu can’t get to 100 percent renewable without off-island assistance. Datta said the utility should open up its scope of what is possible for the island.

On Monday federal officials heard concerns from residents about a plan for offshore wind farms to power Oahu. The residents wanted the officials to consider the wind farms’ effect on a cultural site and the impact on local fishermen.

In HECO’s plan to get the state to 100 percent renewable energy, the utility included installing a $340 million smart-grid system, building utility-scale wind and solar projects, increasing rooftop solar, using liquefied natural gas as a bridge fuel, pursuing energy storage and retiring old fossil fuel plants.

Richard Wallsgrove, program director at Blue Planet Foundation, said he had some concerns about the utility’s LNG analysis. When looking into LNG, HECO compared the price of the fuel with oil but not with other renewable resources.

“It seems to me that just comparing the risk between oil and LNG really leaves out all of the other resources,” he said.

Isaac Moriwake, an attorney with Earthjustice, said that he was disappointed the groups that attended HECO’s meeting weren’t provided a longer period of time to talk.

“We are out of time, and we have only been given 30 minutes,” Moriwake said. “Is this going to be a collaboration? Are we going to be able to have this dialogue? … At the very least we need more meetings.”

Roughly 30 minutes of the meeting was set aside for the groups to ask questions and provide feedback.