3.7. SUMMARY
Sustainability of energy and water in bio‐based systems needs to be collectively considered in a nexus approach. Bio‐based systems are important for attaining sustainable development goals, since they produce fuels and chemicals from renewable feedstock that can substitute petroleum‐based fuels and chemicals. In doing so, bio‐based systems can reduce the dependence on non‐renewable fossil fuels, provide energy and food security, and reduce environmental impacts caused by petroleum‐based fuels and chemicals. However, a large amount of water consumption in bio‐based systems, in both biomass production and processing phases, constitutes a bottleneck in the expansion of bio‐based systems. Therefore, measures for reducing water use in bio‐based systems through efficient irrigation technologies, correct irrigation timing, and recycling of wastewater in biomass processing are being developed.
Bio‐based systems that can sustain itself on energy supplied by renewable sources such as waste biomass from the process itself and other renewable sources of energy, such as wind and water, can play an important role in achieving the SDGs. Reasonable assessments of the water‐energy nexus in bio‐based systems are fundamental in understanding the effects of resource pressure, the interconnection of both resources, and the delicate balances required to develop sustainable bio‐based systems, and hence contribute to the SDGs. In addition, assessment of bio‐based systems in comparison to petroleum‐based systems is important to evaluate their environmental impacts and ensure the sustainability of the bio‐based systems. Water and energy intensity, efficiency and productivity are some of the indicators that can guide us towards more sustainable bio‐based technologies and help attain the SDGs 6, 7, 12, and 13.
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