Electric vehicles could significantly reduce CO2 emissions by 2050

  • Courtesy Kauai EV

    A charging station in Waimea opened in 2019 to help those with electric vehicles who want to cruise to Waimea Canyon and beyond.

MANOA — A faculty member at the University of Hawai‘i at Manoa predicts electric vehicles’ renewable-energy goals will be met, but a Kaua‘i EV expert disputes the goal end date.

Adoption of electric vehicles and faster generation of renewable energy by 2050 will result in 99% less fossil fuel consumed and 93% less CO2 emissions from passenger and freight vehicles on O‘ahu, wrote Katherine McKenzie, of UH-Manoa’s School of Ocean and Earth Science and Technology’s Katherine McKenzie.

McKenzie’s scenario was published in World Electric Vehicle Journal on June 18. McKenzie created mathematical models of four scenarios based on projections for the switch to electric passenger and freight vehicles and renewable-power generation.

She quantified the impacts of fossil-fuel use and CO2 emissions on O‘ahu and found that scenarios with a slower transition to EVs result in billions more gallons of gasoline consumed, and tens of millions more tons of CO2 emitted.

In 2020, average passenger EVs were found to consume the equivalent of 66 gallons of gasoline, seven times less fossil fuel than their gasoline-powered counterparts, which used 455 gallons. Average EVs also cut emissions in half, two metric tons of CO2 versus four metric tons.

“Continuing to purchase anything powered by petroleum locks in emissions and energy insecurity for years to come, at a time when decarbonization is a climate imperative,” said McKenzie. “A shift is needed to energy-efficient modes of travel —such as bicycling, walking and transit, along with reducing vehicle miles traveled by ‘smart’ city planning and remote work, for example.”

These scenarios are intended as examples to assist government, regulatory, public and commercial decision-makers and other stakeholders to better understand future uncertainties, develop strategies and inform the development of policy.

McKenzie will present results from this study at the online conference “Utility Planning for Electric Vehicles on the Grid,” “EVs on the Grid: Impacts, Challenges &System Stability Risks,” in collaboration with Hawaiian Electric Industries, on Tuesday, July 13.

Kaua‘i Electric Vehicle President Sonja Kass agrees with UH’s conclusions to a certain extent. Switching Hawai‘i’s transportation system to electric, powered by renewable resources, will reduce transportation-related emissions to nearly zero, she said.

“I have read many studies and articles that all say the same thing: we absolutely need to move away from burning fossil fuels,” Kass said.

“A few other things have to be considered, though. The production of EVs needs to be powered by renewable energies, and manufacturers need to recycle batteries at the end of their useful life. Tesla is a great example that both can be done economically. I disagree with 2050 though,” as the date to achieve the EV goal. “This is way too late. The switch needs to be happening sooner. In the EU 15% of new cars sold are electric. Some countries are at 70%.”

Noel Morin, president of the Hawai‘i Electric Vehicle Association, said McKenzie’s findings confirm the merits of electric vehicles in helping the state reduce emissions and Hawai‘i’s fossil-fuel dependency and how their efficiency advantages will contribute to pocketbook savings for the community.

“We have a long way to go before we can fully decarbonize,” Morin said.

“I think the progress towards electrification of transportation will continue to accelerate as a result of several converging factors — increasing affordability of long-range EVs; automakers announcing plans to stop the production of gas vehicles and introducing electric trucks and vans; and the passage of laws encouraging adoption of EVs and expansion of public charging infrastructure.”

Morin concluded, “Of course, the challenge is that we must target decarbonization of our energy and transportation much sooner than 2050. The consequences of global warming are with us today, and are becoming increasingly disastrous and deadly,” he said. “We must act with urgency.”


Stephanie Shinno, education and business reporter, can be reached at 245-0424 or sshinno@thegardenisland.com.

  1. RGLadder37 July 9, 2021 12:44 am Reply

    The electric cars must be relearned to fix it. The gas cars are easy because it has been around longer. That is the problem. EPA or some coalition’s agenda is to have people buy electric. But like I said, harder to learn and fix it. I don’t see anybody buying electric.

  2. mark July 9, 2021 7:18 am Reply

    We the public need to know when and where there will be charging stations. Also thinking individuals will need photo voltaic systems at their homes in order to have an electric vehicle. Once again– it is all about the infrastructure!!

  3. EddieG July 9, 2021 12:33 pm Reply

    I enjoy reading articles on our energy future. I am more a fan of Hydrogen than batteries which require the mining for lithium. Silver Peak in Nevada only supplies 2% of the nation’s needs, making our global supply chain at risk of interruption, political or from other reasons. Hydrogen being the most abundant element on earth and the Universe can be created by using renewable energy as well. Electrolysis splits the hydrogen from water. Toyota, one of the leaders in this technology is developing the “Woven City” to demonstrate the future. Years ago I did a speech on the need for a national water and hydrogen grid, where excess water is distributed through canals and pipelines. Moving water is free energy. Produced locally along the grid the infrastructure needs will be met, creating refueling points which are much faster than recharging batteries.

  4. Ngunjiri July 16, 2021 8:34 am Reply

    The transition must not only be energy and zero-carbon but also just. As we develop the electric car we must develop its complementary infrastructure such as charging and also develop human capacity around their technology. By so doing we can have a massive rollout and absorption.

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