Journal of Energy Bioscience 2024, Vol.15, No.3, 208-220 http://bioscipublisher.com/index.php/jeb 214 water resources (Zhao et al., 2020). Additionally, the intensive use of fertilizers in corn farming can lead to water quality issues, such as nitrate pollution, which poses risks to aquatic ecosystems and human health (Zhao et al., 2020; Lark et al., 2022). Effective water management practices are essential to mitigate these impacts and ensure the sustainability of corn ethanol production. 6.4 Strategies for improving sustainability in corn ethanol production To improve the sustainability of corn ethanol production, several strategies can be implemented. Technological advancements in farming practices, such as precision agriculture, can reduce the intensity of fertilizer and fossil fuel use, thereby lowering the carbon footprint of corn ethanol (Scully et al., 2022). Enhancing the efficiency of ethanol refineries and adopting renewable energy sources for ethanol production can also contribute to GHG reductions (Lee et al., 2021; Scully et al., 2022). Additionally, land management practices that increase SOC, such as reduced tillage, cover cropping, and organic matter addition, can mitigate the negative impacts of stover removal and improve soil health (Qin et al., 2018). Policy measures that promote these sustainable practices and incentivize technological innovations are crucial for achieving the environmental benefits of corn ethanol production (Hoekman and Broch, 2018; Lark et al., 2022). 7 Energy Application of Corn Ethanol 7.1 Ethanol as a transportation fuel Corn ethanol has been widely adopted as a transportation fuel due to its potential to reduce greenhouse gas (GHG) emissions and reliance on fossil fuels. The U.S. corn ethanol industry has seen significant growth, with production increasing from 1.6 to 15 billion gallons between 2000 and 2019, driven by supportive biofuel policies. This expansion has resulted in a 23% reduction in carbon intensity (CI) of corn ethanol, contributing to a total GHG emission reduction of 544 million metric tons of CO2 equivalent from 2005 to 2019 (Lee et al., 2021). Additionally, ethanol's role as a biofuel is underscored by its ability to displace petroleum gasoline, thereby reducing overall GHG emissions (Lee et al., 2021). 7.2 Blending with gasoline and its implications Ethanol is commonly blended with gasoline to create ethanol-gasoline mixtures such as E10 (10% ethanol) and E85 (85% ethanol). These blends have been shown to perform better than pure gasoline in terms of fossil fuel depletion and global warming potential. For instance, E10 and E85 blends reduce fossil fuel depletion by 6% and 64%-70%, respectively, and lower global warming potential by 1%-10% and 5%-113%, respectively (Liu et al., 2022). However, these blends also present challenges, such as increased ozone layer depletion, acidification, and eutrophication potential compared to gasoline (Liu et al., 2022). Additionally, dual-alcohol blends, which combine ethanol with other alcohols like methanol or iso-butanol, have been explored to optimize fuel properties and reduce evaporative emissions (Shirazi et al., 2019). 7.3 Comparison with other biofuels and fossil fuels Corn ethanol is often compared with other biofuels and fossil fuels in terms of energy efficiency and environmental impact. While corn ethanol requires 29% more fossil energy than the ethanol fuel produced, it is still more favorable compared to other biofuels like switchgrass and wood biomass, which require 50% and 57% more fossil energy, respectively (Doe et al., 2019). Brazilian sugarcane ethanol, on the other hand, is more efficient, offsetting up to 86% of CO2 emissions compared to oil use and providing a scalable solution to reduce CO2 emissions from the global transport sector (Jaiswal et al., 2017). Despite these benefits, some studies argue that corn ethanol's life-cycle GHG emissions are comparable to or even greater than those of gasoline, questioning its overall environmental advantage (Hill, 2022). 7.4 Future prospects and potential advancements The future of corn ethanol as an energy source lies in improving production efficiency and integrating sustainable practices. Innovations such as the use of energy cane juice in corn ethanol production can enhance fermentation efficiency and reduce resource consumption, making the process more sustainable (Sica et al., 2021). Additionally, advancements in biorefinery technologies that co-produce ethanol and high-value chemicals from lignocellulosic
RkJQdWJsaXNoZXIy MjQ4ODYzMg==