Marcos D.B. Watanabe

Brazilian Soybean Production: Emergy Analysis with an Expanded Scope.

This article offers the results of emergy analysis used to evaluate four different soybean production systems in Brazil that were divided into two main categories: biological models (organic and ecological farms) and industrial models (green-revolution chemical farms and herbicide with no-tillage farms). The biological models show better environmental, economical, and social performance indicators; however, at the national level, discussion of transgenic soybean seed release considers only industrial models without any mention of biological models. Classic emergy analysis shows biological options are the better alternatives but does not explain why decisions taken by farmers and government in Brazil were in opposition to these options. New research is proposed to identify and quantify the external forces that strongly interfere in the definition of public policy for soybean production. New parameters are proposed to enrich emergy methodology: Renewability of each input was considered in emergy calculations and negative externalities were included as additional services.

Hybrid Input-Output Life Cycle Assessment of First- and Second-Generation Ethanol Production Technologies in Brazil

A hybrid approach combining life cycle assessment and input‐output analysis was used to demonstrate the economic and environmental benefits of current and future improvements in agricultural and industrial technologies for ethanol production in Brazilian biorefineries. In this article, three main scenarios were evaluated: first‐generation ethanol production with the average current technology; the improved current technology; and the integration of improved first‐ and second‐generation ethanol production. For the improved first‐generation scenario, a US

Techno-economic analysis and climate change impacts of sugarcane biorefineries considering different time horizons

1 million increase in ethanol demand can give rise to US

Sustainability Assessment Methodologies

2.5 million of total economic activity in the Brazilian economy when direct and indirect purchases of inputs are considered. This value is slightly higher than the economic activity (US

Social life cycle assessment of first and second-generation ethanol production technologies in Brazil

1.8 million) for an energy equivalent amount of gasoline. The integration of first‐ and second‐generation technologies significantly reduces the total greenhouse gas emissions of ethanol production: 14.6 versus 86.4 grams of carbon dioxide equivalent per megajoule (g CO‐eq/MJ) for gasoline. Moreover, emissions of ethanol can be negative (–10.5 g CO‐eq/MJ) when the system boundary is expanded to account for surplus bioelectricity by displacement of natural gas thermal electricity generation considering electricity produced in first‐generation optimized biorefineries.

Use of VSB to Plan Research Programs and Public Policies

BackgroundEthanol production from lignocellulosic feedstocks (also known as 2nd generation or 2G ethanol process) presents a great potential for reducing both ethanol production costs and climate change impacts since agricultural residues and dedicated energy crops are used as feedstock. This study aimed at the quantification of the economic and environmental impacts considering the current and future scenarios of sugarcane biorefineries taking into account not only the improvements of the industrial process but also of biomass production systems. Technology assumptions and scenarios setup were supported by main companies and stakeholders, involved in the lignocellulosic ethanol production chain from Brazil and abroad. For instance, scenarios considered higher efficiencies and lower residence times for pretreatment, enzymatic hydrolysis, and fermentation (including pentoses fermentation); higher sugarcane yields; and introduction of energy cane (a high fiber variety of cane).ResultsEthanol production costs were estimated for different time horizons. In the short term, 2G ethanol presents higher costs compared to 1st generation (1G) ethanol. However, in the long term, 2G ethanol is more competitive, presenting remarkable lower production cost than 1G ethanol, even considering some uncertainties regarding technology and market aspects. In addition, environmental assessment showed that both 1G (in the medium and long term) and 2G ethanol can reduce climate change impacts by more than 80% when compared to gasoline.ConclusionsThis work showed the great potential of 2G ethanol production in terms of economic and environmental aspects. These results can support new research programs and public policies designed to stimulate both production and consumption of 2G ethanol in Brazil, accelerating the path along the learning curve. Some examples of mechanisms include: incentives to the establishment of local equipment and enzyme suppliers; and specific funding programs for the development and use of energy cane.

Use of the VSB to Assess Biorefinery Strategies

This chapter presents some of the most useful techniques applied in the VSB to support both the sustainability assessment and decision making regarding many products and process based on biomass, especially those using sugarcane as feedstock.

Ecosystem services and biogeochemical cycles on a global scale: valuation of water, carbon and nitrogen processes

PurposeThe main goal of this study is to suggest quantitative social metrics to evaluate different sugarcane biorefinery systems in Brazil by exploring a novel hybrid approach integrating social life cycle assessment and input-output analysis.MethodsSocial life cycle assessment is the main methodology for evaluating social aspects based on a life-cycle approach. Using this framework, a hybrid model integrating social life cycle assessment and input-output analysis was introduced to evaluate different social effects of biorefinery scenarios considering workers as the stakeholder category. Job creation, occupational accidents, wage profile, education profile, and gender profile were selected as the main inventory indicators. A case study of three scenarios considering variations in agricultural and industrial technologies (including sugarcane straw recovery and second-generation ethanol production, for instance) was carried out for evaluating present first-generation (1G-basic, 1G-optimized) and future first- and second-generation ethanol production (1G2G).Results and discussionThe 1G-basic scenario leads to higher job creation levels over the supply chain mainly because of the influence of agricultural stage whose workers are mostly employed in sugarcane manual operations. On the other hand, 1G-optimized and 1G2G present supply chains are more reliant on the manufacturing, trade, and services sectors whose workers are associated with a lower level of occupational accidents, higher average wages, higher education level, and more participation of women in the work force.ConclusionsThe use of a novel hybrid approach integrating social life cycle assessment (SLCA) and input-output analysis (IOA) was useful to quantitatively distinguish the social effects over different present and future sugarcane biorefinery supply chains. As a consequence, this approach is very useful to support decision-making processes aiming to improve the sustainability of sugarcane biorefineries taking social aspects into account.

Dynamic emergy accounting of water and carbon ecosystem services: A model to simulate the impacts of land-use change

The VSB comprises a useful framework for assessing research programs, and define and evaluate the effects of public policies. This chapter describes two cases regarding the use of VSB for R&D evaluation—enzyme development and use of energy cane as a new feedstock for sugarcane biorefinery—and a public policy formulation for biogas production and use in the biorefinery context.

De promessa a realidade: como o etanol celulósico pode revolucionar a indústria da cana-de-açúcar: uma avaliação do potencial competitivo e sugestões de política pública

The VSB has been used to assess several configurations of sugarcane biorefineries, including first- and second-generation facilities with alternative features, such as harvesting extension with other crops and integrated production of sugar, ethanol, electricity, and chemicals like n-butanol, as well as thermochemical routes. In this chapter, in-depth examples of selected routes are provided in order to illustrate the different methods that can be applied for the sustainability impact assessment, as well as some results obtained with the VSB