New Possibilities with Bioethanol-Powered Electric Vehicles

Ms. Maki Hoshino

PROFILE

Maki Hoshino completed her master's degree in materials science and engineering at the Graduate School of Engineering of Hokkaido University in 1998. The same year she joined the Nissan Research Center (NRC) at Nissan Motor Co., Ltd., where she engaged in the development of catalysts to reformulate fuel and obtain hydrogen for use in fuel-cell vehicles and fuel-reforming engines. Since 2013 she has been involved in a new research theme toward the further promotion of electric vehicles.

Carbon neutral cycle

  • Sugarcane ->
  • 100% ethanol Ethanol-blended water ->
  • eBio Fuel-Cell?

The World’s First EV Equipped with a SOFC

Nissan announced the e-Bio Fuel-Cell in June 2016. It is a next-generation fuel-cell system that uses bioethanol (100% ethanol or ethanol-blended water) as fuel. This bioethanol is reformulated to hydrogen, which then reacts with oxygen in the atmosphere to produce the electricity that is provided to the vehicle battery and drives the motor. Nissan’s program to equip an electric vehicle (EV) with a solid oxide fuel cell (SOFC) as a power generation unit is the first in the world. The system has many positives. Bioethanol is inexpensive and is already easily available in such countries as Brazil and the United States. It is also relatively safe and thus does not require special infrastructure. The exhaust gas is clean, and running costs are low, on a par with battery EVs. Dramatically increased cruising distance of up to about 600 km is also possible with a single fueling.

The addition of this e-Bio Fuel-Cell and the e-Power which uses an engine as a generator and drives the vehicle with an electric power train, to the Nissan LEAF and other battery EVs will greatly expand the possibilities of these vehicles.

Catalyst development for the reformer that lies at the core of this groundbreaking system is spearheaded by Maki Hoshino. “As long as I'm working in a laboratory, I thought I'd like to be involved in developing technologies and vehicles that are the first of their kind in the world. Today I'm thrilled to have been able to realize that wish,” she says with a smile.

wenty Years in Development Captivated
by Catalyst Research

Soon after joining the company Hoshino was assigned to the research and development team for fuel-cell vehicles, which at that time had just started up. The following year Nissan launched the R’nessa, a reformed methanol fuel-cell vehicle, and she got a taste of the sense of achievement that comes with the public release of research results. Hoshino has since been involved for many years in catalyst development for fuel-cell and gasoline engine vehicles, including the development of catalysts that produce hydrogen from gasoline or bioethanol as demanded by the times. Befitting a researcher who has followed a course of research focused solely on catalysts, her fascination continues.

“I’m still not tired of it,” she says. “Catalysts promote chemical reactions that adsorb or bind certain molecules. But even when we repeat the same experiment, we may not obtain the same reaction because of trivial things like trace impurities in the catalyst or experimental conditions. People who work with mechanical systems have a hard time understanding my fascination with things that cannot be expressed mathematically, but those times when results differ from predictions or hypotheses are actually opportunities. There is serendipity in that chance events can become triggers for major discoveries or later developments. I guess you could say I’m obsessed with catalysts because this kind of unpredictability is so interesting.”

Becoming a Mother Brings Changes
as a Researcher

The development of battery EVs accelerated in the 2000s, and in 2010 Nissan launched a mass-produced electric vehicle, the Nissan LEAF. Even while most attention was on battery EVs, Hoshino’s desire to take advantage of catalyst technology so that liquid fuel could be used remained unchanged. This stemmed from her belief that “if you can resolve the issues in front of you one at a time, even if that takes time, sooner or later you can achieve a practical application.” The use of liquid fuels would mean that energy could be provided with the same refueling time as current gasoline vehicles, and cruising distance could be dramatically increased. Hoshino feels that the time is sure to come when such EVs will be needed.

Around that time Hoshino got married and started a family, which brought huge changes to her lifestyle. She took maternity and childcare leave and afterward worked for a time on a shortened work schedule balancing work and childcare. Female employees before her had continued working while using these systems, so she thought continuing to work would be possible. But at the same time she felt some uncertainty. “Before taking leave I had been working full-time,” she explains, “about 10 hours a day with the inclusion of overtime. Soon after returning to the workplace I was working only about five hours a day, so I thought carefully about how I could produce results while working only half the number of hours.”

Just when she had nearly decided to return to full-time work early, partly because she didn’t want to be a burden on her coworkers, her boss told her, “The important thing is not for you to push yourself to do more work than you can handle now but to pace yourself so that you can continue working later.” That comment changed her way of thinking. She was also encouraged by coworkers who told her that childrearing is a significant contribution to society.

“Thanks to the warm environment,” Hoshino says, “I was able to get on a good spiral of both childcare and work that took me through that time. I am now able to approach my work from two perspectives, as a mother and as a researcher. The ability to use time effectively, eliminating things that are unproductive as much as possible, may be a result of that time.”

Never Give Up雄ou're Sure to Find a Way

Since giving birth, Hoshino’s desire to leave a good environment for the future has grown stronger. What can we do to make a “stress-free car” with as few points of compromise as possible for both users and developers? Many ideas were put forward to answer this question, and the one that was settled on was development of the proposed “e-Bio Fuel-Cell.”

The e-Bio Fuel-Cell with a dramatically longer cruising range on energy provided in a refueling time similar to that of a gasoline vehicle was an idea that Hoshino agreed with. If the bioethanol comes from sugar cane as a raw material, the carbon dioxide absorbed by plants as they grow would offset CO2 emitted by the vehicle as it is driven, achieving a carbon-neutral cycle. Bioethanol is also easy to handle, so no major infrastructure investments would be needed. The ethanol-blended water being investigated is 55% water and 45% ethanol, close to the balance in some alcoholic drinks. Since bioethanol is easy to handle, the possibilities for new fuel supply also expand.

In the past, the demand for ethanol did not grow because of perceived competition with the food supply. Today, though, there are proposed technologies that can produce both sugar and ethanol at higher levels than before using special enzymes in wild species of sugar cane. On isolated islands and other places where energy is difficult to obtain, the use of the e-Bio Fuel-Cell could contribute to both local production and consumption of energy and to regional development. New links between automobiles and society may be on the horizon.

“Not giving up is very important in producing results in research,” Hoshino declares. “If you continue seeking answers to research questions without compromising, you can open your own path to the future.”

Today Hoshino continues her devotion to research and development from the perspectives of a mother, woman and researcher with the aim of creating new automobiles and automobile societies, including future evolution of the e-Bio Fuel-Cell.

Based on an interview carried out in June 2016.

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