Makena Coffman

Who are Driving Electric Vehicles? An analysis of factors that affect EV adoption in Hawaii

May 30, 2018

This study uses data on EV registrations by zipcode in Hawaii to analyze a variety of demographic and transportation factors that might affect EV adoption. After controlling for population and gasoline prices, zip codes with higher income and educational attainment are associated with higher levels of EV adoption. Longer commute times also influence EV adoption […]

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Determinants of Residential Solar Photovoltaic Adoption

February 7, 2018

Hawaii is a leader in distributed solar photovoltaic (PV) adoption. It has the highest rate of PV-based electricity penetration in the U.S. and rivals global front runners. The policy impetus towards large-scale adoption of renewable energy comes from the Renewable Portfolio Standard, with a target of 40% net electricity sales from renewable sources by the […]

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A Scoping Study for Climate Action Planning in Kauaʻi

October 16, 2017

This report documents best practices for county-level climate action plans (CAPs), with considerations for Kaua‘i. A CAP is primarily a process by which a jurisdiction agrees upon greenhouse gas (GHG) reduction strategies and policies. This report is based on the gathering of studies and protocols addressing climate action planning and GHG mitigation best practices.

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The Role of Policy and Peers in EV Adoption

June 2, 2017

By Sherilyn Wee, Makena Coffman and Sumner LaCroix Electric vehicles (EVs) can be a cleaner means of transportation compared to cars with traditional gasoline engines. They have the added benefit of being able to provide support to the electric power grid—an increasingly important attribute in states like Hawaii with high levels of intermittent renewable energy. […]

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Estimating the Opportunity for Load-Shifting in Hawaii: An Analysis of Proposed Residential Time-of-Use Rates

August 2, 2016

Hawaii’s largest electric utility, Hawaiian Electric Company (HECO) and its subsidiaries recently proposed a Time of Use (TOU) pricing scheme for residential rates. The TOU scheme has three tiers of prices: daytime, on-peak, and nighttime. The proposed rates have the highest cost during the on-peak period from 5pm to 10pm. For Oahu, the lowest cost […]

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Electric Vehicle Greenhouse Gas Emission Assessment for Hawaii

July 28, 2016

This study estimates greenhouse gas (GHG) emissions of electric vehicles (EVs) compared to that of other popular and similar cars in Hawaii, by county over an assumption of 150,000 miles driven. The GHG benefits of EVs depend critically on the electricity system from which they derive their power. The analysis shows that EVs statewide are […]

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A Status Update on Federal GHG Emissions Reduction Policy for Hawaii

January 4, 2016

By Paul Bernstein, Makena Coffman and Sherilyn Wee In early August, President Obama announced and the U.S. Environmental Protection Agency (EPA) released the final details for the Clean Power Plan (CPP). These rules are designed to lower levels of carbon pollution from existing U.S. power plants – aiming to curb U.S. electric sector emissions by […]

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Research Driven Energy Policy

November 5, 2015

By Carl Bonham, Makena Coffman, and Michael Roberts Hawaii is in the midst of transforming its electricity system into one with a lot more renewable energy. It’s an exciting time, but also a challenging one that is forcing the State to make tough decisions amid many uncertainties. There appears to be confusion about who bears […]

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Electric Vehicle Lifecycle Cost Assessment for Hawaii

September 8, 2015

This study develops a model to estimate the total cost of ownership of electric vehicles (EVs) in comparison to similar internal combustion engine (ICEVs) and hybrid electric vehicles (HEVs). The model includes issues related to purchase/finance, insurance, maintenance, resale value, future fuel prices and access to solar photovoltaic (PV). It also estimates the impact of […]

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