Bio-based succinic acid has the potential to become a platform chemical, i.e. a key building block for deriving both commodity and high-value chemicals, which makes it an attractive compound in a bio-based economy. A few companies and industrial consortia have begun to develop its industrial production on a large scale. A life cycle assessment of different bio-based succinic acid production processes, based on dextrose from corn, was performed to investigate their non-renewable energy use (NREU) and greenhouse gas (GHG) emissions, from cradle-to-factory gate in Europe. Three processes were studied, i.e. (i) low pH yeast fermentation with downstream processing (DSP) by direct crystallization, (ii) anaerobic fermentation to succinate salt at neutral pH (pH7) and subsequent DSP by electrodialysis, and (iii) a similar process producing ammonium sulfate as co-product in DSP. These processes are compared to the production of petrochemical maleic anhydride, succinic acid, and adipic acid. Low pH yeast fermentation to succinic acid with direct crystallization was found to have signifi cantly lower GHG emissions and NREU, compared to other fermentation routes and three petrochemical routes. However, the disparity in GHG emissions between this process and the electrodialysis process becomes less prominent if one considers a cleaner electricity mix than the current European production mix. Moreover, this study highlights that the allocation approach in corn wet milling and the succinic acid plant location strongly infl uence the results. Overall, the results suggest that low pH yeast fermentation with direct crystallization is the most benefi cial process to bio-based succinic acid from an environmental perspective.

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Several studies that have assessed the role of bioenergy in the energy system have primarily focused on electricity, heat, and road transport. However, sectors that have few alternatives to biomass, namely aviation and the chemical industry, are expected to become increasingly important. We have extended a bottom‐up energy systems model with fossil‐based and bio‐based chemicals and with renewable jet fuels to assess the deployment of biomass conversion technologies in the Netherlands until 2030. The model comprises detailed cost‐structures and mid‐term developments for the energy system with detailed cost‐supply curves for biomass, renewable energy technologies, and carbon capture and storage. The framework incorporates multi‐output processes, such as biorefineries, to address cross‐sectoral synergies. To capture the uncertainty in technical progress, technology development scenarios are used to assess cost‐optimal biomass utilization pathways over time. Slow technical progress (LowTech) leads to biomass applications for heating, first‐generation biofuels from hydrotreated oils, and bio‐based chemicals based on first‐generation fermentation systems. Enhanced technology development (HighTech) allows the production of second‐generation biofuels, large volumes of diverse bio‐based chemicals and renewable jet fuels. The required biomass may range from 230 PJ (LowTech) to 300 PJ (HighTech) in 2030, supplied primarily from imported resources. Both scenarios show that, under existing policies, CO2 emissions will only gradually be reduced to reach 1990 levels (140–145 Mt CO2). Further scenario analysis is recommended to assess model sensitivity and the necessary preconditions for future biomass conversion pathways and robust directions towards the required greenhouse‐gas mitigation pathways. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.

India’s biofuel programme relies on ethanol production from sugarcane molasses. However, there is limited insight on environmental impacts across the Indian ethanol production chain. This study closes this gap by assessing the environmental impacts of ethanol production from sugarcane molasses in Uttar Pradesh, India. A comparative analysis with south-central Brazilian sugarcane ethanol is also presented to compare the performance of sugarcane molasses-based ethanol with sugarcane juice-based ethanol. Methods The production process is assessed by a cradle-togate life cycle assessment. The multifunctionality problem is solved by applying two variants of system expansion and economic allocation. Environmental impacts are assessed with Impact 2002+ and results are presented at the midpoint level for greenhouse gas emissions, non-renewable energy use, freshwater eutrophication and water use. Furthermore, results include impacts on human health and ecosystem quality at the damage level. Sensitivity analysis is also performed on key contributing parameters such as pesticides, stillage treatment and irrigation water use. Results and discussion It is found that, compared to Brazilian ethanol, Indian ethanol causes lower or comparable greenhouse gas emissions (0.09–0.64 kgCO2eq/kgethanolIN, 0.46–0.63 kgCO2eq/kgethanolBR), non-renewable energy use (−0.3–6.3 MJ/kgethanolIN, 1–4MJ/kgethanolBR), human health impacts (3.6·10−6 DALY/kgethanolIN, 4·10−6 DALY/kgethanolBR) and ecosystem impairment (2.5 PDF·m2·year/kgethanolIN, 3.3 PDF·m2·year/kgethanolBR). One reason is that Indian ethanol is exclusively produced from molasses, a co-product of sugar production, resulting in allocation of the environmental burden. Additionally, Indian sugar mills and distilleries produce surplus electricity for which they receive credits for displacing grid electricity of relatively high CO2 emission intensity. When economic allocation is applied, the greenhouse gas emissions for Indian and Brazilian ethanol are comparable. Non-renewable energy use is higher for Indian ethanol, primarily due to energy requirements for irrigation. For water use and related impacts, Indian ethanol scores worse due groundwater irrigation, despite the dampening effect of allocation. The variation on greenhouse gas emissions and non-renewable energy use of Indian ills is much larger for high and low performance than the respective systems in Brazil. Conclusions Important measures can be taken across the production chain to improve the environmental performance of Indian ethanol production (e.g. avoiding the use of specific pesticides, avoiding the disposal of untreated stillage, transition to water efficient crops). However, to meet the targets of the Indian ethanol blending programme, displacement effects are likely to occur in countries which export ethanol. To assess such effects, a consequential study needs to be prepared

Bioenergy as well as bioenergy with carbon capture and storage are key options to embark on cost-efficient trajectories that realize climate targets. Most studies have not yet assessed the influence on these trajectories of emerging bioeconomy sectors such as biochemicals and renewable jet fuels (RJFs). To support a systems transition, there is also need to demonstrate the impact on the energy system of technology development, biomass and fossil fuel prices. We aim to close this gap by assessing least-cost pathways to 2030 for a number of scenarios applied to the energy system of the Netherlands, using a cost-minimization model. The type and magnitude of biomass deployment are highly influenced by technology development, fossil fuel prices and ambitions to mitigate climate change. Across all scenarios, biomass consumption ranges between 180 and 760 PJ and national emissions between 82 and 178 Mt CO 2 . High technology development leads to additional 100-270 PJ of biomass consumption and 8-20 Mt CO 2 emission reduction compared to low technology development counterparts. In high technology development scenarios, additional emission reduction is primarily achieved by bioenergy and carbon capture and storage. Traditional sectors, namely industrial biomass heat and biofuels, supply 61-87% of bioenergy, while wind turbines are the main supplier of renewable electricity. Low technology pathways show lower biochemical output by 50-75%, do not supply RJFs and do not utilize additional biomass compared to high technology development. In most scenarios the emission reduction targets for the Netherlands are not met, as additional reduction of 10-45 Mt CO 2 is needed. Stronger climate policy is required, especially in view of fluctuating fossil fuel prices, which are shown to be a key determinant of bioeconomy development. Nonetheless, high technology development is a no-regrets option to realize deep emission reduction as it also ensures stable growth for the bioeconomy even under unfavourable conditions.