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Abstract: Hydrogen is produced via steam methane reforming (SMR) for bitumen upgrading which results in significant greenhouse gas (GHG) emissions. Wind energy based hydrogen can reduce the GHG footprint of the bitumen upgrading industry. This paper is aimed at developing a detailed data-intensive techno-economic model for assessment of hydrogen production from wind energy via the electrolysis of water. The proposed wind/hydrogen plant is based on an expansion of an existing wind farm with unit wind turbine size of 1.8 MW and with a dual functionality of hydrogen production and electricity generation. An electrolyser size of 240 kW (50 Nm3 H2/h) and 360 kW (90 Nm3 H2/h) proved to be the optimal sizes for constant and variable flow rate electrolysers, respectively. The electrolyser sizes aforementioned yielded a minimum hydrogen production price at base case conditions of $10.15/kg H2 and $7.55/kg H2. The inclusion of a Feed-in-Tariff (FIT) of $0.13/kWh renders the production price of hydrogen equal to SMR i.e. $0.96/kg H2, with an internal rate of return (IRR) of 24%. The minimum hydrogen delivery cost was $4.96/kg H2 at base case conditions. The life cycle CO2 emissions is 6.35 kg CO2/kg H2 including hydrogen delivery to the upgrader via compressed gas trucks. [Copyright &y& Elsevier]

Abstract: Biomass can be used for the production of fuels, and chemicals with reduced life cycle (greenhouse gas) emissions. Currently, these fuels and chemicals are produced mainly from natural gas and other fossil fuels. In Western Canada, forest residue biomass is gasified for the production of syngas which is further synthesized to produce different fuels and chemicals. Two types of gasifiers: the atmospheric pressure gasifier (commercially known as SilvaGas) and the pressurized gasifier (commercially known as RENUGAS) are considered for syngas production. The production costs of methanol, (dimethyl ether), (Fischer-Tropsch) fuels, and ammonia are $0.29/kg, $0.47/kg, $0.97/kg, and $2.09/kg, respectively, for a SilvaGas-based gasification plant with a capacity of 2000 dry tonnes/day. The cost of producing methanol, DME, F-T fuels, and ammonia in a RENUGAS-based plant are $0.45/kg, $0.69/kg, $1.53/kg, and $2.72/kg, respectively, for a plant capacity of 2000 dry tonnes/day. The minimum cost of producing methanol, DME, F-T fuels, and ammonia are $0.28/kg, $0.44/kg, $0.94/kg, and $2.06/kg at plant capacities of 3000, 3500, 4000, and 3000 dry tonnes/day, respectively, using the SilvaGas-based gasification process. Biomass-based fuels and chemicals are expensive compared to fuels and chemicals derived from fossil fuels, and carbon credits can help them become competitive. [Copyright &y& Elsevier]

Abstract: The environmental performance of production and distribution of densified form of lignocellulosic biomass (i.e., agri-residue based pellets) in Western Canada in terms of energy and greenhouse gas (GHG) emission was assessed. The results show that energy usage and resulted emissions are highest in field activities especially if emission and energy are attributed to straw in farming stage where nitrogen fertilizer is the highest contributor. Significant reduction of energy use (64%) and emission (65%) are possible if the organic fertilizer is used in farming. Adopting the zero tillage option instead of conventional practice results in energy saving (10%) and emission reduction (8%). From the scenario analyses it is also evident that using biomass as an energy source during drying or no drying in pellet production stage or using alternate mode (i.e., truck and train) of transport for pellet delivery result in less than 5% reduction of the energy use and emissions compared to the base case. Agri-pellet has the potential to offset substantial amount of GHG emission compared to other fuel sources including wood pellets. The energy and emission of production chain of agri-pellets may vary between countries but overall trend compared to other fuel sources would be similar. [Copyright &y& Elsevier]