Toyota continues to be committed to the green revolution, developing next-generation environment-friendly vehicles and pouring money into renewable energy research. Toyota may be one step closer to its goal to commercializing cellulosic ethanol by 2020 with its development of a new super-yeast used to produce cellulosic ethanol.
Yeast is used to ferment plant sugars in the biofuel production process, but naturally occurring yeasts don’t break down plant sugars very well. As a result cellulosic ethanol production is costly compared to its yields.
A study by the National Academies published earlier this month found that cellulosic ethanol is currently not a commercially sustainable alternative to petroleum. To make cellulosic ethanol more sustainable and cost-competitive, the study calls for more research to be done into increasing the conversion yield from biomass to fuels.
And this is exactly what Toyota is doing. Its super-yeast is very efficient at breaking down plant sugar and has a high resistance to acetic acid, which inhibits fermentation. According to Toyota, its new yeast has the highest ethanol fermentation density levels in the world—approximately 47 g/liter—and is expected to improve bio-fuel yield and significantly reduce production costs.
This appears to be a promising step on the road toward a truly sustainable energy solution. And because Toyota’s cellulosic ethanol production relies on non-editable plant sources—and not corn—it believes it will have less impact on world food supplies.
The National Academies study was critical of corn-based ethanol, stating that corn ethanol production can increase greenhouse gas emissions and result in other environmental pollutants. It seems less clear how the use of non-editable crops like switchgrass impact the environment and what the economic fall-out will be if and when cellulosic ethanol is produced on a commercial-scale.
What do you think? Is there a sustainable future in biofuel?