Economic performance and GHG emission intensity of sugarcane‐ and eucalyptus‐derived biofuels and biobased chemicals in Brazil

Abstract

Biomass feedstock can be used for the production of biofuels or biobased chemicals to reduce anthropogenic greenhouse gas (GHG) emissions. Earlier studies about the techno-economic performance of biofuel or biobased chemical production varied in biomass feedstock, conversion process, and other techno-economic assumptions. This made a fair comparison between different industrial processing pathways difficult. The aim of this study is to quantify uniformly the factorygate production costs and the GHG emission intensity of biobased ethanol, ethylene, 1,3-propanediol (PDO), and succinic acid, and to compare them with each other and their respective fossil equivalent products. Brazilian sugarcane and eucalyptus are used as biomass feedstock in this study. A uniform approach is applied to determine the production costs and GHG emission intensity of biobased products, taking into account feedstock supply, biobased product yield, capital investment, energy, labor, maintenance, and processing inputs. Economic performance and net avoided GHG emissions of biobased chemicals depend on various uncertain factors, so this study pays particular attention to uncertainty by means of a Monte Carlo analysis. A sensitivity analysis is also performed. As there is uncertainty associated with the parameters used for biobased product yield, feedstock cost, fixed capital investment, industrial scale, and energy costs, the results are presented in ranges. The 60% confidence interval ranges of the biobased product production costs are 0.64-1.10 US$ kg −1 ethanol, 1.18-2.05 US$ kg −1 ethylene, 1.37-2.40 US$ kg −1 1,3-PDO, and 951 Modeling and Analysis: Costs and GHG emissions of biobased value chains JGG Jonker et al.1.91-2.57 US$ kg −1 succinic acid. The cost ranges of all biobased products partly or completely overlap with the ranges of the production costs of the fossil equivalent products. The results show that sugarcane-based 1,3-PDO and to a lesser extent succinic acid have the highest potential benefit. The ranges of GHG emission reduction are 1.29-2.16, 3.37-4.12, 2.54-5.91, and 0.47-5.22 CO 2eq kg −1 biobased product for ethanol, ethylene, 1,3-PDO, and succinic acid respectively. Considering the potential GHG emission reduction and profit per hectare, the pathways using sugarcane score are generally better than eucalyptus feedstock due to the high yield of sugarcane in Brazil. Overall, it was not possible to choose a clear winner, (a) because the best performing biobased product strongly depends on the chosen metric, and (b) because of the large ranges found, especially for PDO and succinic acid, independent of the chosen metric. To quantify the performance better, more data are required regarding the biobased product yield, equipment costs, and energy consumption of biobased industrial pathways, but also about the production costs and GHG emission intensity of fossil-equivalent products. 952JGG Jonker et al.Modeling and Analysis: Costs and GHG emissions of biobased value chains

Are eucalyptus harvest residues a truly burden-free biomass source for bioenergy? A deeper look into biorefinery process design and Life Cycle Assessment

“…Considering the share attributed to forestry activities on EFR hydrous ethanol GWP (10.1%), this would correspond to 0.08 kgCO2eq.kgethanol -1 , or 0.2 kgCO2eq.kgethanol -1 , if EFR retrieval solutions are also accounted. These figures sit within the mentioned GWP range (Jonker et al, 2019), which suggests this variance is the result of the process data inserted in the LCI. Liang et al (2017) explored the use of conifer harvest residues as the raw material for ethanol production.…”

“…While this limits the options for benchmarking, comparisons can be drawn with ethanol produced from eucalyptus wood and other forest residual biomass. Jonker et al (2019) explored the potential for chemicals and fuel production from eucalyptus, which included bioethanol. The reported greenhouse gas (GHG) emissions ranges from 0.1 to 0.2 kgCO2eq -1 per kg of fuel, calculated in a cradle-to-gate approach, regionalized for Brazil.…”

System analysis of the bio‐based economy in Colombia: A bottom‐up energy system model and scenario analysis

“… * The lower, reference and upper ranges are based on the cost of eucalyptus reported by Jonker et al ., 104 Smeets and Faaij, 71 and Lap et al ., 26 respectively. …”

Technoeconomic evaluation and risk assessment of bioprocessess and bio-refineries

“…The selection of the most promising bio-based technologies among many different alternative options is a challenge in many areas of science and engineering (Bonatsos et al, 2020). Earlier techno-economic studies are intended to expose the technical and economic features of bioconversion technologies, but the assumptions that are used do not take into account the dynamic nature of these technologies (Jonker et al, 2019). As already mentioned in the introduction section, bio-based processes are strongly affected by a massive number of uncertainties that are associated with the process design and model development, or can be associated with bioproduct demand and prices, investment cost and process-inherent parameters.…”

“…The production of chemicals and energy from renewable raw materials faces two major challenges. The first challenge is to have a high contribution to anthropogenic greenhouse gas (GHG) emissions reduction and secondly, the production costs of bio-based products should be able to compete fossil reference products (Jonker et al, 2019). Representative examples of bio-based chemicals, which have been satisfactory produced in commercial scales, are industrial enzymes, ethanol-based biofuels, 1,3-propanediol and lactic acid.…”