Potential to increase biofuels output from a gasification-based biorefinery using external hydrogen supply (enhancement) was investigated. Up to 2.6 or 3.1-fold increase in biofuel output could be ...attained for gasoline or methane production over reference plant configurations, respectively. Such enhanced process designs become economically attractive over non-enhanced designs when the average cost of low-carbon hydrogen falls below 2.2–2.8 €/kg, depending on the process configuration. If all sustainably available wastes and residues in the European Union (197 Mt/a) were collected and converted only to biofuels, using maximal hydrogen enhancement, the daily production would amount to 1.8–2.8 million oil equivalent barrels. This total supply of hydrogen enhanced biofuels could displace up to 41–63 per cent of the EU (European Union)'s road transport fuel demand in 2030, again depending on the choice of process design.
•Up to 2.6 or 3.1-fold increase in biofuel output attained via hydrogen enhancement.•Enhanced processes economically attractive when cost of hydrogen below 2.2–2.8 €/kg.•Hydrogen enhanced biofuels could displace 41–63% of the EU's road transport fuels in 2030.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Large-scale systems suitable for the production of synthetic natural gas (SNG), methanol or gasoline (MTG) are examined using a self-consistent design, simulation and cost analysis framework. Three ...basic production routes are considered: (1) production from biomass via gasification; (2) from carbon dioxide and electricity via water electrolysis; (3) from biomass and electricity via hybrid process combining elements from routes (1) and (2). Process designs are developed based on technologies that are either commercially available or successfully demonstrated at precommercial scale. The prospective economics of future facilities coproducing fuels and district heat are evaluated from the perspective of a synthetic fuel producer. The levelised production costs range from 18–37 €/GJ for natural gas, 21–40 €/GJ for methanol and 23–48 €/GJ for gasoline, depending on the production route. For a given end-product, the lowest costs are associated with thermochemical plant configurations, followed by hybrid and electrochemical plants.
•Production of synthetic fuels from biomass residues, CO2 and electricity is investigated.•Different process configurations are compared based on their mass and energy balances.•Prospective economics are evaluated under alternative feedstock price assumptions.•Thermochemical plants have the lowest and electrochemical plants the highest costs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We compare different approaches for the preparation of carbon monoxide-rich synthesis gas (syngas) for Fischer–Tropsch (FT) synthesis from carbon dioxide (CO2) using a self-consistent design and ...process simulation framework. Three alternative methods for suppling heat to the syngas preparation step are investigated, namely: allothermal from combustion (COMB), autothermal from partial oxidation (POX) and autothermal from electric resistance (ER) heating. In addition, two alternative design approaches for the syngas preparation step are investigated, namely: once-through (OT) and recycle (RC). The combination of these alternatives gives six basic configurations, each characterized by distinctive plant designs that have been individually modelled and analyzed. Carbon efficiencies (from CO2 to FT syncrude) are 50–55% for the OT designs and 65–89% for the RC designs, depending on the heat supply method. Thermal efficiencies (from electricity to FT syncrude) are 33–41% for configurations when using low temperature electrolyzer, and 48–59% when using high temperature electrolyzer. Of the RC designs, both the highest carbon efficiency and thermal efficiency was observed for the ER configuration, followed by POX and COMB configurations.
•We study GHG emissions of hydrogen enhanced synthetic biofuels from solid biomass.•We provide a review for the newly proposed EU sustainability criteria.•The carbon intensity of electricity used to ...produce hydrogen is a defining factor.•To pass future GHG criteria electricity with under 110gCO2/kWh emission is needed.•We also study the effect of adding an emission factor for the wood feedstock.
The European Commission has proposed a minimum share of 3.6% for advanced biofuels in transport in 2030. Satisfying this target using synthetic biofuels would require 48–62Mt/a of forest residue feedstock. If all biofuel plants were maximally enhanced with additional hydrogen input, the biomass demand would be reduced by 35Mt to 16–24Mt/a. As sustainable biomass is a limited resource, such drastic improvements in the efficiency of biomass use have a favourable impact on biomass availability. In this work we assume electrolysis of water as the source of hydrogen and investigate the GHG emission balances of hydrogen enhanced biofuels using the calculation method provided in the European Union’s sustainability criteria for biofuels. The required 70% emission saving compared to fossil fuels is achieved when the carbon intensity of electricity remains under 84–110gCO2/kWh, depending on the process configuration. In addition, we study the possibility that an emission factor could be allocated to the wood biomass, referring to recent discussions on climate impacts of forest bioenergy. Without hydrogen enhancement, the emission factor needs to remain below 13gCO2/MJwood to meet the 70% requirement, while for hydrogen-enhanced configurations it could increase to 36gCO2/MJwood, under the assumption of zero emission electricity.
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We develop a framework for comparing carbon-neutral synthetic fuels (CNSFs) with battery electric vehicles (BEVs) as alternatives to reducing CO2 emissions from light-duty vehicles. CNSFs can be ...divided into fuels produced from biomass via gasification and electrofuels produced from CO2 and water using electricity. We develop CNSF cost estimates for first-of-a-kind plants operating at commercial scale. Although already competitive over short distances, we find that longer-range BEVs are likely to remain more expensive than CNSFs even if low (∼$125/kWh) battery costs are achieved, and all three options would require carbon prices in excess of $130/tCO2 or oil prices in excess of $100/bbl to become commercially viable relative to petroleum. The viability of electrofuels ultimately depends on access to low-cost, ultra-low-carbon power systems or sources of zero-carbon electricity with high annual availability. Priorities should include deploying a portfolio of CNSF technologies to help appraise decarbonization pathways, economies of scale, and learning by doing.
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•Costs estimates for decarbonized synthetic fuels produced by first-of-a-kind plants•Side-by-side analysis of advanced biofuels, electrofuels, and battery electric vehicles•All three options require CO2 prices >$130/tCO2 or oil prices >$100/bbl
Global energy demand for transport more than doubled from 45 EJ in 1973 to 110 EJ in 2014, increasing its share of total final consumption from 23% to 28%. As a result, sectoral CO2 emissions have more than doubled since petroleum products dominate (96% of transportation sector energy consumption in 2016). To be consistent with Paris Agreement targets, under the International Energy Agency (IEA) baseline projection, demand would need to fall from 160 EJ in 2050 to 102 EJ, or roughly current levels, but would need to be substantially less carbon-intensive. Decarbonizing transport will require a combination of sustainable fuels (advanced biofuels and electrofuels produced from electricity and CO2) and new powertrains (battery electric vehicles or BEVs). The greatest reductions will need to come from decarbonizing road transport, which is seen as the easiest sector for BEVs and the most challenging for synthetic fuels.
Battery electric vehicles (BEVs) are often seen as best suited to reduce emissions from light-duty vehicles, whereas synthetic fuels (whether advanced biofuels or so-called electrofuels) are touted as drop-in substitutes for more costly end uses such as aviation or heavy-goods vehicles. We provide a side-by-side comparison of biofuels, electrofuels, and BEVs using the data from recent projects to explore the conditions needed for these different options to become viable in decarbonizing passenger transport.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We study the role of solar heat in decarbonization of a Nordic district heating (DH) network, where most of the annual heat demand is satisfied with bioenergy. We use actual data from a Finnish ...municipality to create a dynamic model of the heating system with Apros® simulation software. With the help of modelling, we examine various decarbonization scenarios for the existing heating system, using different combinations solar thermal collectors, thermal energy storage (TES) and limitations on how and when solar heat can access the system. According to results, zero emissions during the summer can be achieved with annual solar share of 13.2% and at 44 €/MWh levelized cost of heat (LCoH), if the integration is supported by TES and a careful planning of solar heat integration. Our results show that a simple approach of pursuing for a maximal solar share does not necessarily lead to a reduction in carbon emission or in LCoH. In fact, aiming at higher solar shares of 15–25% in our case system, actually increase greenhouse gas emissions compared to the base case. This highlights the importance of focusing on emissions reductions instead of simple addition of renewable energy when DH utilities plan for solar heat investments.
•Decarbonization of a Nordic district heating network with solar heat and bioenergy.•Simulation of different combinations of bioenergy, solar heat and energy storage.•Zero emissions during summer with solar share of 13.2% and heat cost of 44 €/MWh.•Solar heat integration requires energy storage and detailed integration strategy.•Higher 15–25% solar shares increase emissions without limitation on solar heat use.
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The potential to increase biofuel output from a fast pyrolysis-based biorefinery through hydrogen enhancement is assessed for thermal fast pyrolysis (TFP) and catalytic pyrolysis (CAT) processes ...featuring bio-oil upgrade into gasoline, diesel and heavy hydrocarbon fractions. Results show that utilizing pyrolysis process off-gases to produce synthetic natural gas with an external hydrogen source could provide up to 48.2% (TFP) and 61.2% (CAT) reductions in biomass resource utilization. These savings are enabled by significantly improved carbon efficiency of the hydrogen enhanced designs, with efficiencies increasing from 40.5% to 66.3% for TFP and from 28.9% to 58.6% for CAT. Although the CAT process has a lower biofuel yield than the TFP process, it has a higher potential for hydrogen enhancement and achieves a higher biofuel output than TFP when fully enhanced with external hydrogen. The trade-off to the improved biofuel yield (higher carbon efficiency) is the substantial need for electricity to produce hydrogen via electrolysis, as for every megajoule (MJ) of biomass feedstock, 0.65–0.66 MJ of electricity is needed for the electrolyser.
•Thermal catalytic pyrolysis biorefinery concepts with hydrogen enhancement were assessed.•Increased carbon efficiency from hydrogen enhancement grants up to 61% biomass resource savings.•Catalytic pyrolysis provides higher enhancement potential and higher biofuel output.•The need for low-carbon electricity totals 0.65–0.66 MJ per MJ biomass feedstock.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A process model for pressurised fluidised-bed gasification of biomass was developed using Aspen Plus simulation software. Eight main blocks were used to model the fluidised-bed gasifier, complemented ...with FORTRAN subroutines nested in the programme to simulate hydrocarbon and NH3 formation as well as carbon conversion. The model was validated with experimental data derived from a PDU-scale test rig operated with various types of biomass. The model was shown to be suitable for simulating the gasification of pine sawdust, pine and eucalyptus chips as well as forest residues, but not for pine bark or wheat straw.
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