Hawaii residents traditionally built with cooling in mind. Windows were placed to maximize cross ventilation and jalousies let in the breeze. 

But with global temperatures rising rapidly – the world just had its hottest July ever – and decreasing trade winds, Hawaii’s residents are relying more and more on what used to be a rare luxury: air conditioning. 

“As a kid growing up in Ewa Beach, we never needed air conditioning,” said Shannon Tangonan, a spokeswoman for Hawaiian Electric Co. “Now, you really do need it. It’s almost unbearable. We go as long as we can without turning on that AC, but come noon, one o’clock, it gets to the point where it’s like, OK, turn on the AC.” 

In 1970, only 14% of Oahu’s residential utility customers, and 2% of those on the neighbor islands, had AC, according to surveys by HECO.

Today, AC is part of life for 68% of Oahu’s residential HECO customers, more than half of those on Maui, Molokai and Lanai and 32% of those on the Big Island. That doesn’t include businesses or the 1,000 Hawaii classrooms that have put in AC in recent years. 

The spike is part of a global trend. As the world warms and becomes more developed, the demand for air conditioning in hotter regions like Hawaii is expected to skyrocket. While the comfort of cooling may improve quality of life, experts project the soaring energy demands will have major monetary and environmental impacts. Ironically, increased air conditioning usage threatens to exacerbate global warming. 

“It’s this vicious cycle that’s going to drive up our greenhouse gas emissions unless we’re smart about it,” said Jeff Mikulina, executive director of the Blue Planet Foundation, a Hawaii nonprofit that advocates for clean energy.

The trend is occurring as Hawaii pursues a state mandate to produce all of its electricity with renewable energy by 2045. Increasing AC usage is an obstacle to weaning ourselves off of coal, said Brian Kealoha, executive director of Hawaii Energy, a ratepayer-funded energy efficiency and conservation program.

“As we think about how we get to our 100% clean energy goal, part of how we were going to get there was a reduction of our usage,” he said. “But with air conditioning now, in a lot of cases, we’re increasing that overall usage.” 

An Energy ‘Blind Spot’

Air conditioning worsens climate change in two ways. 

For one, leaks of refrigerants from individual AC units release potent heat-trapping chemicals called hydrofluorocarbons. In 2016, nearly 200 parties from around the world signed on to the Kigali Agreement to phase down these pollutants. The United States was not among them. President Donald Trump has resisted joining the effort despite bipartisan support. 

Then there are the energy implications. Global energy demand from air conditioners is expected to triple by 2050, according to a 2018 report from The International Energy Agency, a group that advocates for reliable, affordable and sustainable energy solutions. The global stock of air conditioners in buildings is about 1.6 billion today, the report says, but it is expected to balloon to 5.6 billion by 2050.

That’s 10 new ACs sold every second for the next 30 years, the report says.

“Growing electricity demand for air conditioning is one of the most critical blind spots in today’s energy debate,” IEA Director Fatih Birol said last year.

To meet growing power demands from AC, the IEA reported some areas will need to build new power plants. According to HECO, that won’t be the case in Hawaii. Oahu is preparing for the closure in 2022 of its only coal-fired power plant in Kapolei. 

“We definitely have the supply,” Tangonan said. “That’s not an issue.”

Hawaii’s challenge will be meeting energy demands and the state’s renewable energy goals at the same time. For HECO, it will be a “careful balancing act,” Tangonan said.

More AC units means more energy demand, she said, and hotter days mean those units work harder to keep spaces cool.

“The year-over-year increase in demand will require reliable resources,” she said. “The wind is not always blowing. The sun is not always shining. We have to make sure we have a lot of battery storage and that we’re developing a real diverse portfolio of resources.”

Currently, HECO doesn’t have much storage, Tangonan said, but it has approved seven project proposals from solar energy storage providers.

“The goal is to move off of imported oil,” she said. 

Local energy leaders say they are focused on promoting energy efficiency and minimizing usage.

“It would be the end of the world, literally, if everyone (globally) got air conditioning,” Mikulina said. “The ideal is building homes that don’t require the use of AC.”

County officials on the islands have approved or are reviewing requirements on new buildings that would make them more energy-efficient and align with a 2015 state energy code update. The state code, modeled after the national International Energy Conservation Code, applies only to new construction or structures undergoing significant renovations, Hawaii Chief Energy Officer Carilyn Shon said in an emailed statement. States and municipalities adopting the national code have the option of tailoring it to their needs.

“For example, if an existing home were to undergo a roof replacement the homeowner would have the option of following the national energy code, which requires insulating the roof, or follow the Hawaii amendment, which requires reflective roof coatings, attic ventilation or radiant barriers,” Shon said in the statement. She declined multiple interview requests.

Circular Impact

For some Hawaii workers, the rise of air conditioning is a welcome development. Connor Emerson, a 24-year-old student at Honolulu Community College, said he noticed higher temperatures and saw a career opportunity.

“I know there’s a demand for it,” he said. “There aren’t enough technicians to meet the customers’ needs, so I figured it was a good trade. Always job security. It’s not like construction where there are peak seasons.”

In summer, it’s a guarantee that there will be even more installations and repair calls, said Emerson, who is working part-time at Innovative Air Conditioning.

For some businesses, the wait time for customers’ AC installation is two or three weeks, said Emerson’s teacher, Steven Chow.

“They’re backed up,” Chow said. “And (customers) are like, ‘Well, we can’t wait that long. Can you get it in sooner?’ And they end up trying to call somebody else, and it’s the same thing everywhere else.”

Many consumers tend to rush to stores when temperatures tick up and they can’t take it anymore, Kealoha said. It’s a move that costs them more in the long run.

“You’re buying whatever they have on sale,” he said. “For us, that’s a big challenge because portable units or window air conditioners are not very efficient.”

Less efficiency means higher utility bills, Kealoha said. Split systems that are Energy Star-rated – meaning they’re approved by the U.S. Environmental Protection Agency – require a greater up-front investment but use less energy and save users money over time, Kealoha said. 

If heat in Hawaii were to become unbearable and AC became a necessity for health and safety, as it has in places like Phoenix, property owners could be faced with the expensive prospect of sealing their homes for AC. In a state known for its high cost of living and comparatively low wages, many people would not be able to afford a home cooling renovation. 

Officials said they haven’t explored what it would mean if a large number of Hawaii homes needed to be retrofitted for AC. The question of whether low-income residents would be able to get public assistance to cool their houses hasn’t been studied, they said.

“Oftentimes when bad things happen, people with little resources are the ones that suffer the most and that would be no different here,” said Gavin Thornton, executive director of the Hawaii Appleseed Center for Law and Economic Justice.

Ultimately, Hawaii Energy is working to increase the number of efficient air conditioning units on the market and encouraging customers to limit their usage, especially during peak times, Kealoha said. Doing so will help move Hawaii into a greener future.

“There is a circular impact of what’s happening here,” he said. “Carbon emissions raise the temperature, it gets hotter, and you use more AC and more energy. Until we move to 100% renewable, the cycle starts to feed upon itself.”

This story is part of Covering Climate Now, a global collaboration of more than 250 news outlets to strengthen coverage of the climate story.