Economic and environmental impact marginal analysis of biorefinery products for policy targets

A simple biofuel production system can be first examined for its policy 8 compliance in terms of GHG emission reduction target relative to fossil-based 9 counterparts. More integrated and optimised biorefinery systems with polygeneration 10 can then be evolved with the aid of graphical analysis of marginal emission savings 11 vs. additional economic margins. This bottom-up approach helps to achieve greater 12 GHG emission cut by integrated systems design and thereby setting a more stringent 13 benchmark to support policies towards achieving climate change mitigation goals. 14 The combined Economic Value and Environmental Impact analysis is a multi-level 15 methodology that can be used to represent biorefinery system performances as an 16 aggregate of differential economic and environmental impact margins of biorefinery 17 products. The methodology is extended in this paper to support process integration 18 strategies that allow achieving policy compliance of biorefinery products in terms of 19 GHG emission savings. An economic and environmental impact profile of the 20 products is introduced for a graphical visualisation of economic costs and values as 21 well as deficits and surpluses in environmental impact savings. The effectiveness of 22 the extended methodology has been demonstrated using a Jatropha-based biorefinery 23 system converting Jatropha seed into biodiesel, glycerol and cake, as a case study. 24