As Central Maui Landfill grows, a private company touts turning county’s waste into renewable natural gas

With the Central Maui Landfill’s limited capacity expanding and 400,000 tons of Lahaina fire debris on its way, a company is proposing a $225 million, privately funded project to convert solid waste from homes and businesses into renewable natural gas. 

E&K Aloha ‘Aina — which includes business partners Keoni Gomes, a Maui contractor with a background in civil engineering, and Erfan Ibrahim, a Berkeley-educated nuclear engineer — is spearheading the project, which would be located on a parcel of land at the corner of Pūlehu and Hansen roads, just a mile and a half away from the landfill. 

“What we’re trying to do is take something that has already been used and extracting the energy from that product that would normally just go to a landfill,” Gomes said. “Especially here in Maui, where all we’re doing is landfilling. There’s hardly any recycling or recapturing of energy. … The bulk of the waste in Maui is going to the landfill.”

The project calls for taking waste from the landfill to the site where automated systems would tear open the trash bags and cut, crush and shred the waste into a manageable size, according to a draft environmental assessment for the project that was released Monday.

Artificial intelligence would then be used to sort through the waste and remove recyclable materials like glass and hazardous substances, with the final product checked by workers. 

The material then would be dried and compressed into small briquettes that would be fed into a gasifier, a device that converts solid material into gas, which would then be purified and refined to create renewable natural gas. 

Natural gas is a fossil fuel that can be found in layers of rock, deposits of crude oil or pockets beneath the ocean floor, according to the U.S. Energy Information Administration. In the United States, it’s mostly used for generating electricity and space heating. About 60% of U.S. homes use natural gas for heating, cooking and drying clothes.

Gomes said E&K’s natural gas would be renewable because it’s turning an already used waste product into a fuel that can be put to use again. According to the U.S. Department of Energy, it’s “fully interchangeable with conventional natural gas.”

Maui currently doesn’t have a gasification facility, and there’s a reason — the island doesn’t have the needed number of people or the infrastructure of pipelines islandwide to support it. But Hawai‘i Gas does have a pipeline system in Kahului, and some homes and businesses have tanks, but overall it’s not enough to consume the fuel the E&K facility would make, Gomes said. So, it would have to be used in a limited capacity on Maui or shipped to O‘ahu for use. 

“I think it would become more of a standard to use renewable energy once it’s available,” Gomes said. “We’d love for it to stay on Maui. That’s the whole goal. In the short term, I understand that there’s a lot of work that needs to be done. But I think in the long term, it’ll be very, very feasible and probably economically beneficial to the public to utilize what we produce.”

The plant is expected to be operational in 2029 if all goes according to plan. The project requires approval of its environmental assessment, construction permits, and an amendment to a state Land Use Commission permit to allow waste-to-fuel activities.

E&K would lease a 12.8-acre plot of land currently owned by Gomes’ family, though he said they are not involved in the project. 

The project would be privately funded. Gomes said he could not disclose the names of the funders, but did say they were not from Maui. Some are in Hawai‘i and others on the Mainland, with the possibility of international investors. 

E&K’s proposal comes at a time when the Central Maui Landfill is taking on the first loads of debris from the August 2023 Lahaina wildfire that are currently stored at a temporary site in Olowalu. 

Even before the convoy of trucks started the debris transfer earlier this month, the Central Maui Landfill built in the 1980s was struggling with capacity issues. It is the disposal site for most of the trash on the island.

“One of the problems that we’ve had for awhile in Maui is figuring out where to take our waste,” Gomes said. “Over the years we determined that the Central Maui Landfill, although they recently added a lot of capacity, truly cannot sustain in the long term the amount of waste that is being taken in.”

In fiscal year 2022, just before the fire, the Central Maui Landfill took in 295,939 tons of waste, about 96% of all materials disposed of countywide that year, according to the county’s Integrated Solid Waste Management Plan, which was updated last year. The plan says the landfill is expected to reach capacity in 2033, though the timeline could be extended if more sections are added. 

But not all of the county’s waste stays in its four landfills. In fiscal year 2019, for example, the county produced 352,865 tons of waste, with 63% going to landfills and the other 37% recycled or diverted. 

In December, the Maui County Council approved Mayor Richard Bissen’s proposal to buy 79 acres for $4 million to expand the landfill and use 14 acres as a permanent disposal site for debris from the wildfire. 

Gomes said his project wouldn’t take any fire debris due to its sensitivity of containing the remains of the thousands of homes destroyed in Lahaina. This debris is being handled separately. Instead, the goal is to take the typical rubbish from homes, businesses, resorts and hotels.

In the first year of operation, E&K expects the plant’s capacity to be 96,500 metric tons of solid waste and 1,930 metric tons of mixed plastic waste. The plan is to grow capacity in the coming years to eventually take on all of the solid waste that the landfill currently processes.

The proposal already has backing at the state and county level. 

Gov. Josh Green said in a letter of support in December that the privately funded project would mitigate the need for public funding to expand the Central Maui Landfill or build more landfills.

“I look forward to seeing this plant built and commissioned as soon as possible to address the critical waste problem in Maui County,” he said.

The Maui County Department of Environmental Management supports the project as well. Director Shayne Agawa said in a letter of support in December that the department plans to plans to put out a request for proposals for “a comprehensive solid waste solution for Maui County” in the near future.

“Moving forward with your venture has the potential to put you in a good position, if you had interest, to compete for a role in that future solid waste solution,” Agawa said. 

Both Green and Agawa agreed that a waste-to-fuel project is better than a waste-to-energy project. A waste-to-energy project uses the waste as fuel to create energy such as electricity or heat. It requires more approvals, and it’s uncertain who would use it, “as Hawaiian Electric has been reluctant to partner due to the required energy rate, which has been at a premium to other energy sources, including renewables,” Agawa said. A waste-to-fuel project “does not rely on the electric utility for success and can instead delivery renewable natural gas to various off takers to displace traditional fossil fuel use.”

Maui County Council Member Gabe Johnson, who chairs the council’s Agriculture, Diversification, Environment and Public Transportation Committee, also said he was supportive of the project, though “of course we need to sort out the details.”

“I think we need to look at the statewide goal to make us 100% renewable energy users by 2045,” Johnson said via text. “When the department of environmental management has more details to share I look forward to hearing about it in my ADEPT committee.”

Doug McLeod, manager of DKK Energy Services and former Maui County energy commissioner, said “the selling feature” of renewable natural gas is that it doesn’t emit as much emissions as conventional natural gas. But he cautioned that even if it is renewable, that doesn’t mean it won’t have an impact on the environment. It contains hydrocarbons, and when those are burned, they release carbon.

“It probably would help make Maui more resilient in the sense of we have a situation where fuel resupply couldn’t come into the island,” McLeod said. “But at a sort of countrywide or planetary level, it’s still basically burning stuff, sending it into the atmosphere. And this is a very expensive way to get a product that is little better in terms of emissions than natural gas.”

A project like this would also likely require a lot of water, McLeod said. E&K says it plans to drill its own well to use for the facility.

“If there’s not enough water on Maui for the people today, is adding another major industrial use that would export some of the product, does that make sense?” McLeod said.

For now, natural gas “is not a product that’s getting any meaningful amount of use on Maui.” But, McLeod said, the technology works, and he could see the renewable natural gas being used for facilities such as Hawaiian Electric’s aging units at Mā‘alaea or its future 40-megawatt renewable energy project in Puʻunēnē.

When asked if it was worth investing in a product like this amid the push toward cleaner energy, Gomes said that renewable fuels have less of an environmental impact, and that the plant will take products that would normally sit in a landfill for decades and put them to use.

Gomes added that the process of creating the gas is “not incineration, so you’re not burning it.” He said that gasification involves a lot of pressure and some heat to basically change the molecules into gas from a solid state. The facility also will be enclosed, and the company plans to use advanced technology already being deployed in Europe to limit emissions.

As for whether the benefits offset the impacts, especially when the product could go off island, Gomes said “the long-term goal is for Maui to reap the benefits of the renewable energy that we’re producing.”

“But in order for that to happen … infrastructure needs to be built,” he said.

For Gomes, resiliency is a big selling point at a time when analysts worry oil and gas prices could spike if Iran moved to close the Strait of Hormuz, a key shipping path for the global oil supply, in retaliation for the U.S. bombing its nuclear facilities.

“We have conflicts here and there that cause oil prices to fluctuate, and most of the time not in our favor,” Gomes said. “So reducing our dependency on outside products, such as fuel, will ultimately make Hawai‘i a more stable economical environment for everybody.”

Comments on the project are open through July 23 and can be sent to Maui County, the approving agency, at environmental.mgmt@co.maui.hi.us.