Utilization of eucalyptus for bioelectricity production in brazil via fast pyrolysis: a techno-economic analysis

Authors: PIGHINELLI, ANNA - Embrapa; Schaffer, Mark; Boateng, Akwasi

Submitted to: Renewable Energy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/9/2017
Publication Date: 1/1/2018
Citation: Pighinelli, A.L., Schaffer, M.A., Boateng, A.A. 2018. Utilization of eucalyptus for bioelectricity production in brazil via fast pyrolysis: a techno-economic analysis. Renewable Energy. 119:590-597.

Interpretive Summary: Bio-oil is the liquid obtained from the thermal decomposition of biomass, also known as pyrolysis. This liquid has several applications including commodity chemicals, fuels and as a feedstock to electricity generation. The economic feasibility regarding the application of bio-oil to generate electricity was evaluated using models developed by using simulation software named Pro/II. In the study, two different scenarios based on eucalyptus wood pyrolysis were compared based on operational conditions in Brazil: single biomass to bio-oil facility (2000 metric ton of wood per day) and a distributed, where several small facilities with aggregate capacity similar to the single one both feeding into one centralized electricity generation facility. From the economic analysis, it was concluded that a selling price of US$0.23 (single) and US$0.37 (distributed) per kWh was necessary to ensure to the investor to make some profit out of the electricity selling. The single capacity facility is found to have better economic benefits compared to the aggregated plants of small sizes. The cost of eucalyptus wood, utilities and equipment had some influence on the unit production cost of bioelectricity. Based on the current price of electricity and other costs, pyrolysis of eucalyptus wood for bioelectricity is not competitive with fossil-based electricity. However, due to the constant increase in the electricity cost, cyclic crises in the wood sector in Brazil and concerns about the greenhouse gas (GHG) emissions in the world at large, the pyrolysis of eucalyptus wood for bioelectricity may become competitive with fossil-based electricity in the future.

Technical Abstract: In this study, a process model of a 2000 metric ton per day (MTPD) eucalyptus Tail Gas Reactive Pyrolysis (TGRP) and electricity generation plant was developed and simulated in SimSci Pro/II software for the purpose of evaluating its techno-economic viability in Brazil. Two scenarios were compared based on operational conditions in the country: a single biomass to bio-oil TGRP production facility and a distributed/satellite processing that consists of several small TGRP production facilities with aggregate capacity similar to the single one, both feeding into one centralized electricity generation plant. The selling price at the breakeven point of the electricity generated via TGRP was estimated to be US$0.11 and US$0.20 per kWh for the single and the distributed scenarios respectively, considering a 10-year payback period. The single capacity pyrolysis and electricity generation facility is found to have better economic benefits over the distributed plants of small sizes under the current conditions in Brazil. The results therefore indicate that pyrolysis of eucalyptus wood for electricity in a single facility is competitive with the current electricity cost in Brazil (range of US$0.08-0.13/kWh) while the distributed scenario is 54% higher. Considering auxiliary benefits such as climate change and carbon credits, plus the continuous increasing in the electricity market price in Brazil, even the distributed scenario can be competitive in the future.