Power up with bio-ethanol

Nissan has developed a stationary system fuelled by bio-ethanol that’s capable of high-efficiency power generation. 

Trials have begun at the company’s Tochigi plant in Japan aimed at improving power generation capacity toward full-scale operations from 2030.

In 2016, Nissan became the first automotive company in the world to create a vehicular propulsion system powered by a solid-oxide fuel cell (SOFC) run by bio-ethanol. It’s now applying this SOFC development experience to stationary power-generation systems.

SOFCs can be easily paired with reformers that operate at high temperatures and can generate electricity using hydrogen obtained by reforming various types of fuels that react with oxygen, including ethanol, natural gas and LP gas. 

Operations at high temperatures promote high catalytic activity, enabling the SOFC to achieve a high-power generation efficiency of 70 per cent when compared to 60 per cent for polymer electrolyte fuel cells.

Looking ahead, the development of a metal-supported cell, which is a component of the SOFC stack, will help to enhance cell strength. Start-up and shutdown times can be shortened, and load-following operations performed in response to sudden fluctuations in output demand. 

This will enable effective SOFC operation in the future when it is anticipated the system will be used in conjunction with renewable energy.

The stationary generation system will be fuelled by bio-ethanol made from sorghum. This component will commence from 2025.

Although sorghum bio-ethanol emits carbon dioxide (CO2) during SOFC power generation, that CO2 is absorbed from the atmosphere during the sorghum growth process. This contributes to realising a carbon-neutral cycle whereby CO2 increases are effectively reduced to zero.

“There are major changes occurring in the transition from the internal combustion engine to electric vehicles,” says Kazuhiko Murata, Nissan’s corporate vice-president of powertrains.

“Nissan is taking up technological development challenges in new areas and SOFC power generation is one of our strengths. We will continue to contribute to the promotion of electrification and efforts toward carbon neutrality.”

The company say it is committed to achieving carbon neutrality across its operations and product life cycle by 2050.

The goal is to fully electrify plant equipment by 2050. To achieve carbon neutrality at production facilities, all electricity used will be generated from renewable energy sources or with on-site fuel cells that use alternative fuels.

Sorghum characteristics

• It’s an annual herbaceous plant of the grass family that grows quickly and can be harvested in about three months, enabling multiple harvests every year when grown in suitable conditions.

• Given its adaptability to cold and dry regions, it can be grown in a wide range of regions and different soils.

• The stem is used as a raw material for ethanol and the grain is used for food, meaning there’s no competition with food production.

• Stem waste after pressing can also be used in biomass power generation.