In an effort to help Honolulu achieve its clean-energy goals, the City Council this week passed a measure that requires many Oahu building owners to report and publicly publish data about their energy and water use.

The proposed requirement applies to buildings over 25,000 square feet. It exempts residential buildings with fewer than five units.

In addition to submitting annual reports that include information on matters ranging from greenhouse gas emissions to energy use by fuel type and water use, the building owners would also report their Energy Star score — a numeric rating about energy efficiency created by the U.S. Environmental Protection Agency. The score is determined, in part, by taking information about the building, such as its size and location, and calculating potential high- and low- performing scenarios.

The Council voted unanimously in favor of the bill Wednesday, and Mayor Rick Blangiardi has until July 21 to decide whether to sign the measure into law.

Blue Planet Foundation Executive Director Melissa Miyashiro said reporting energy use is a valuable first step to figuring out how to save energy.

“Through that information, then you can make decisions about what’s a positive, cost-effective way to reduce a building’s energy burden,” Miyashiro said. Also, she said, “building owners and managers can make strategic business decisions” about where and when to pursue clean-energy upgrades.

The city already requires its buildings to report this green information. The requirement prompted an initial 5% decrease in energy and water use, said Josh Stanbro, a policy fellow at Elemental Excelerator, which funds startups developing green technology. Stanbro was also executive director of the city’s Office of Climate Change, Sustainability and Resiliency under former Mayor Kirk Caldwell.

Noting that some buildings have been able to reach a 50% decrease, Stanbro said, “If you make it (reporting) visible … they can compare the building next to them.” And if a neighboring building is using considerably lower amount of energy or far fewer gallons of water, “They’re like, ‘Wait, why is mine so high?’” That, in turn, prompts questions such as, “‘Is there something that we can do?’ And usually, when they ask that question, the answer is yes.”

Stanbro said much of the new technology and innovation as well as the startups coming through Elemental Excelerator are focused on “how we use energy so that we’re just sipping and not guzzling from the energy cup.”

He pointed out that the proposed city requirement may be especially helpful in commercial buildings where not all workers have returned in-person due to the COVID-19 pandemic. “If there’s only two people on the floor, and they’re in this corner, we can just AC that area and do lighting in that area. And the system knows that. Or they can do certain floors at a time — or better yet, you set it (indoor temperature) to the ambient temperature outside so we’re only going to cool as much as we need to.”

Miyashiro said energy reporting focuses on buildings instead of single-family homes because buildings make up about 33% of energy use on the island.

“If you look at Oahu specifically, we don’t have a lot of land to kind of expand outward and build new energy- efficient buildings. So there’s going to be a lot of important conversation and a lot of important work on retrofitting existing buildings because so much of our infrastructure is already built,” she said.

“We also have to look at our existing building stock and figure out how we can reduce carbon emissions in those buildings. And then, in turn, it has the added benefit of saving money.”

If Blangiardi signs off on the proposal, buildings with at least 100,000 square feet must submit the first round of reporting by June 30. Buildings starting at 50,000 square feet — would have until June 30, 2024, to comply with the new law. And buildings over 25,000 square feet would have until June 30, 2025.

Those who miss the reporting deadline would have 60 days to comply with requirements after being notified of their noncompliance. After that they can be fined up to $1,000 and, after reaching that mark, fined up to $100 a day until they submit their report. The total fines cannot exceed $5,000 a year.

Building Industry Association of Hawaii President Daryl Takamiya said while he supports saving energy, he’s concerned that the reporting of information could lead to more building mandates, which could slow down the pace of construction or increase the cost of construction. Such an upshot, he said, could increase the cost of housing.

“That’s the direction that they’re going in,” Takamiya said. “The goal is terrific. And I completely understand that. It’s just how you go about doing it right, and trying to avoid the unexpected, unintended consequences of it.”

Takamiya said the BIA would have preferred that the bill offer incentives rather than penalties to comply.