Comparative life cycle assessment of three biohydrogen pathways.
A life cycle assessment was performed to quantify and compare the energetic and environmental performances of hydrogen from wheat straw (WS-H(2)), sweet sorghum stalk (SSS-H(2)), and steam potato peels (SPP-H(2)). Inventory data were derived from a pilot plant. Impacts were assessed using the impact 2002+ method. When co-product was not considered, the greenhouse gas (GHG) emissions were 5.60 kg CO(2eq) kg(-1) H(2) for WS-H(2), 5.32 kg CO(2eq) kg(-1) H(2) for SSS-H(2), and 5.18 kg CO(2eq) kg(-1) H(2) for SPP-H(2). BioH(2) pathways reduced GHG emissions by 52-56% compared to diesel and by 54-57% compared to steam methane reforming production of H(2). The energy ratios (ER) were also comparable: 1.08 for WS-H(2), 1.14 for SSS-H(2) and 1.17 for SPP-H(2). A shift from SPP-H(2) to WS-H(2) would therefore not affect the ER and GHG emissions of these BioH(2) pathways. When co-product was considered, a shift from SPP-H(2) to WS-H(2) or SSS-H(2) decreased the ER, while increasing the GHG emissions significantly. Co-product yield should be considered when selecting BioH(2) feedstocks.
University of Antwerp, Department of Biology, Wilrijk, Belgium. sylvestre.njakoudjomo@ua.ac.be
Sylvestre Njakou
SN
Djomo
Dagnija
D
Blumberga
D056804:Biofuels / Q000032:analysis*; D003198:Computer Simulation; D004735:Energy Transfer; D017752:Greenhouse Effect; D006859:Hydrogen / Q000737:chemistry*; D008956:Models, Chemical; D035261:Plant Components, Aerial / Q000737:chemistry*; D011198:Solanum tuberosum / Q000737:chemistry*; D045868:Sorghum / Q000737:chemistry*; D013227:Steam; D014908:Triticum / Q000737:chemistry*
D056804:Biofuels; D013227:Steam; D006859:Hydrogen