Germany
Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany
Jul 2017
Publication
“Linking the power and transport sectors—Part 1” describes the general principle of “sector coupling” (SC) develops a working definition intended of the concept to be of utility to the international scientific community contains a literature review that provides an overview of relevant scientific papers on this topic and conducts a rudimentary analysis of the linking of the power and transport sectors on a worldwide EU and German level. The aim of this follow-on paper is to outline an approach to the modelling of SC. Therefore a study of Germany as a case study was conducted. This study assumes a high share of renewable energy sources (RES) contributing to the grid and significant proportion of fuel cell vehicles (FCVs) in the year 2050 along with a dedicated hydrogen pipeline grid to meet hydrogen demand. To construct a model of this nature the model environment “METIS” (models for energy transformation and integration systems) we developed will be described in more detail in this paper. Within this framework a detailed model of the power and transport sector in Germany will be presented in this paper and the rationale behind its assumptions described. Furthermore an intensive result analysis for the power surplus utilization of electrolysis hydrogen pipeline and economic considerations has been conducted to show the potential outcomes of modelling SC. It is hoped that this will serve as a basis for researchers to apply this framework in future to models and analysis with an international focus.
New Control Strategy for Heating Portable Fuel Cell Power Systems for Energy-Efficient and Reliable Operation
Dec 2022
Publication
Using hydrogen fuel cells for power systems temperature conditions are important for efficient and reliable operations especially in low-temperature environments. A heating system with an electrical energy buffer is therefore required for reliable operation. There is a research gap in finding an appropriate control strategy regarding energy efficiency and reliable operations for different environmental conditions. This paper investigates heating strategies for the subfreezing start of a fuel cell for portable applications at an early development stage to enable frontloading in product engineering. The strategies were investigated by simulation and experiment. A prototype for such a system was built and tested for subfreezing start-ups and non-subfreezing start-ups. This was done by heating the fuel cell system with different control strategies to test their efficiency. It was found that operating strategies to heat up the fuel cell system can ensure a more reliable and energy efficient operation. The heating strategy needs to be adjusted according to the ambient conditions as this influences the required heating energy efficiency and reliable operation of the system. A differentiation in the control strategy between subfreezing and non-subfreezing temperatures is recommended due to reliability reasons.
Risk Assessment and Mitigation Evaluation for Hydrogen Vehicles in Private Garages. Experiments and Modelling
Sep 2021
Publication
Governments and local authorities introduce new incentives and regulations for cleaner mobility as part of their environmental strategies to address energy challenges. Fuel cell electric vehicles (FCEVs) are becoming increasingly important and will extend beyond captive fleets reaching private users. Research on hydrogen safety issues is currently led in several projects in order to highlight and manage risks of FCEVs in confined spaces such as tunnels underground parkings repair garages etc. But what about private garages - that involve specific geometries volumes congestion ventilation? This study has been carried out in the framework of PRHyVATE JIP project which aims at better understanding hydrogen build-up and distribution in a private garage. The investigation went through different rates and modes of ventilation. As first step an HAZID (Hazard Identification) has been realized for a generic FCEV. This preliminary work allowed to select and prioritize accidental release scenarios to be explored experimentally with helium in a 40-m3 garage. Several configurations of release ventilation modes and congestion – in transient regime and at steady state – have been tested. Then analytical and numerical calculation approaches have been applied and adjusted to develop a simplified methodology. This methodology takes into account natural ventilation for assessment of hydrogen accumulation and mitigation means optimization. Finally a global risk evaluation – including ignition of a flammable hydrogen-air mixture – has been performed to account for the mostly feared events and to evaluate their consequences in a private garage. Thus preliminary recommendations good practices and safety features for safely parking FCEVs in private garages can be proposed.
Cryogenic and Ambient Gaseous Hydrogen Blowdown with Discharge Line Effects
Sep 2021
Publication
The present work performed within the PRESLHY EC-project presents a simplified 1-d transient modelling methodology to account for discharge line effects during blowdown. The current formulation includes friction extra resistance area change and heat transfer through the discharge line walls and is able to calculate the mass flow rate and distribution of all physical variables along the discharge line. Choked flow at any time during the transient is calculated using the Possible Impossible Flow (PIF) algorithm. Hydrogen single phase physical properties and vapour-liquid equilibrium are calculated using the Helmholtz Free Energy (HFE) formulation. Homogeneous Equilibrium Mixture (HEM) model is used for two-phase physical properties. Validation is performed against the new experiments with compressed gaseous hydrogen performed at the DISCHA facility in the framework of PRESLHY (200 bar ambient and cryogenic initial tank temperature 77 K and 4 nozzle diameters 0.5 1 2 and 4 mm) and an older experiment at 900 bar ambient temperature and 2 mm nozzle. Predictions are compared against measured data from the experiments and the relative importance of line heat transfer compared to flow resistance is analysed.
Hydrogen-Assisted Cracking in GMA Welding of High-Strength Structural Steel—A New Look into This Issue at Narrow Groove
Jun 2021
Publication
Modern arc processes such as the modified spray arc (Mod. SA) have been developed for gas metal arc welding of high-strength structural steels with which even narrow weld seams can be welded. High-strength joints are subjected to increasingly stringent requirements in terms of welding processing and the resulting component performance. In the present work this challenge is to be met by clarifying the influences on hydrogen-assisted cracking (HAC) in a high-strength structural steel S960QL. Adapted samples analogous to the self-restraint TEKKEN test are used and analyzed with respect to crack formation microstructure diffusible hydrogen concentration and residual stresses. The variation of the seam opening angle of the test seams is between 30° and 60°. To prevent HAC the effectiveness of a dehydrogenation heat treatment (DHT) from the welding heat is investigated. As a result the weld metals produced at reduced weld opening angle show slightly higher hydrogen concentrations on average. In addition increased micro- as well as macro-crack formation can be observed on these weld metal samples. On all samples without DHT cracks in the root notch occur due to HAC which can be prevented by DHT immediately after welding.
Alkaline Water Electrolysis Powered by Renewable Energy: A Review
Feb 2020
Publication
Alkaline water electrolysis is a key technology for large-scale hydrogen production powered by renewable energy. As conventional electrolyzers are designed for operation at fixed process conditions the implementation of fluctuating and highly intermittent renewable energy is challenging. This contribution shows the recent state of system descriptions for alkaline water electrolysis and renewable energies such as solar and wind power. Each component of a hydrogen energy system needs to be optimized to increase the operation time and system efficiency. Only in this way can hydrogen produced by electrolysis processes be competitive with the conventional path based on fossil energy sources. Conventional alkaline water electrolyzers show a limited part-load range due to an increased gas impurity at low power availability. As explosive mixtures of hydrogen and oxygen must be prevented a safety shutdown is performed when reaching specific gas contamination. Furthermore the cell voltage should be optimized to maintain a high efficiency. While photovoltaic panels can be directly coupled to alkaline water electrolyzers wind turbines require suitable converters with additional losses. By combining alkaline water electrolysis with hydrogen storage tanks and fuel cells power grid stabilization can be performed. As a consequence the conventional spinning reserve can be reduced which additionally lowers the carbon dioxide emissions.
Hydrogen Embrittlement Mechanism in Fatigue Behavior of Austenitic and Martensitic Stainless Steels
May 2018
Publication
In the present study the influence of hydrogen on the fatigue behavior of the high strength martensitic stainless steel X3CrNiMo13-4 and the metastable austenitic stainless steels X2Crni19-11 with various nickel contents was examined in the low and high cycle fatigue regime. The focus of the investigations were the changes in the mechanisms of short crack propagation. Experiments in laboratory air with uncharged and precharged specimen and uncharged specimen in pressurized hydrogen were carried out. The aim of the ongoing investigation was to determine and quantitatively describe the predominant processes of hydrogen embrittlement and their influence on the short fatigue crack morphology and crack growth rate. In addition simulations were carried out on the short fatigue crack growth in order to develop a detailed insight into the hydrogen embrittlement mechanisms relevant for cyclic loading conditions. It was found that a lower nickel content and a higher martensite content of the samples led to a higher susceptibility to hydrogen embrittlement. In addition crack propagation and crack path could be simulated well with the simulation model.
Fundamentals, Materials, and Machine Learning of Polymer Electrolyte Membrane Fuel Cell Technology
Jun 2020
Publication
Polymer electrolyte membrane (PEM) fuel cells are electrochemical devices that directly convert the chemical energy stored in fuel into electrical energy with a practical conversion efficiency as high as 65%. In the past years significant progress has been made in PEM fuel cell commercialization. By 2019 there were over 19000 fuel cell electric vehicles (FCEV) and 340 hydrogen refueling stations (HRF) in the U.S. (~8000 and 44 respectively) Japan (~3600 and 112 respectively) South Korea (~5000 and 34 respectively) Europe (~2500 and 140 respectively) and China (~110 and 12 respectively). Japan South Korea and China plan to build approximately 3000 HRF stations by 2030. In 2019 Hyundai Nexo and Toyota Mirai accounted for approximately 63% and 32% of the total sales with a driving range of 380 and 312 miles and a mile per gallon (MPGe) of 65 and 67 respectively. Fundamentals of PEM fuel cells play a crucial role in the technological advancement to improve fuel cell performance/durability and reduce cost. Several key aspects for fuel cell design operational control and material development such as durability electrocatalyst materials water and thermal management dynamic operation and cold start are briefly explained in this work. Machine learning and artificial intelligence (AI) have received increasing attention in material/energy development. This review also discusses their applications and potential in the development of fundamental knowledge and correlations material selection and improvement cell design and optimization system control power management and monitoring of operation health for PEM fuel cells along with main physics in PEM fuel cells for physics-informed machine learning. The objective of this review is three fold: (1) to present the most recent status of PEM fuel cell applications in the portable stationary and transportation sectors; (2) to describe the important fundamentals for the further advancement of fuel cell technology in terms of design and control optimization cost reduction and durability improvement; and (3) to explain machine learning physics-informed deep learning and AI methods and describe their significant potentials in PEM fuel cell research and development (R&D).
Boosting the H2 Production Efficiency via Photocatalytic Organic Reforming: The Role of Additional Hole Scavenging System
Nov 2021
Publication
The simultaneous photocatalytic H2 evolution with environmental remediation over semiconducting metal oxides is a fascinating process for sustainable fuel production. However most of the previously reported photocatalytic reforming showed nonstoichiometric amounts of the evolved H2 when organic substrates were used. To explain the reasons for this phenomenon a careful analysis of the products and intermediates in gas and aqueous phases upon the photocatalytic hydrogen evolution from oxalic acid using Pt/TiO2 was performed. A quadrupole mass spectrometer (QMS) was used for the continuous flow monitoring of the evolved gases while high performance ion chromatography (HPIC) isotopic labeling and electron paramagnetic resonance (EPR) were employed to understand the reactions in the solution. The entire consumption of oxalic acid led to a ~30% lower H2 amount than theoretically expected. Due to the contribution of the photoKolbe reaction mechanism a tiny amount of formic acid was produced then disappeared shortly after the complete consumption of oxalic acid. Nevertheless a much lower concentration of formic acid was generated compared to the nonstoichiometric difference between the formed H2 and the consumed oxalic acid. Isotopic labeling measurements showed that the evolved H2 HD and/or D2 matched those of the solvent; however using D2O decreased the reaction rate. Interestingly the presence of KI as an additional hole scavenger with oxalic acid had a considerable impact on the reaction mechanism and thus the hydrogen yield as indicated by the QMS and the EPR measurements. The added KI promoted H2 evolution to reach the theoretically predictable amount and inhibited the formation of intermediates without affecting the oxalic acid degradation rate. The proposed mechanism by which KI boosts the photocatalytic performance is of great importance in enhancing the overall energy efficiency for hydrogen production via photocatalytic organic reforming.
Impacts of Greenhouse Gas Neutrality Strategies on Gas Infrastructure and Costs: Implications from Case Studies Based on French and German GHG-neutral Scenarios
Sep 2022
Publication
The European Union’s target to reach greenhouse gas neutrality by 2050 calls for a sharp decrease in the consumption of natural gas. This study assesses impacts of greenhouse gas neutrality on the gas system taking France and Germany as two case studies which illustrate a wide range of potential developments within the European Union. Based on a review of French and German GHG-neutral scenarios it explores impacts on gas infrastructure and estimates the changes in end-user methane price considering a business-as-usual and an optimised infrastructure pathway. Our results show that gas supply and demand radically change by mid-century across various scenarios. Moreover the analysis suggests that deep transformations of the gas infrastructure are required and that according to the existing pricing mechanisms the end-user price of methane will increase driven by the switch to low-carbon gases and intensified by infrastructure costs.
Hydrogen-powered Aviation in Germany: A Macroeconomic Perspective and Methodological Approach of Fuel Supply Chain Integration into an Economy-wide Dataset
Oct 2022
Publication
The hydrogen (H2) momentum affects the aviation sector. However a macroeconomic consideration is currently missing. To address this research gap the paper derives a methodology for evaluating macroeconomic effects of H2 in aviation and applies this approach to Germany. Three goals are addressed: (1) Construction of a German macroeconomic database. (2) Translation of H2 supply chains to the system of national accounts. (3) Implementation of H2-powered aviation into the macroeconomic data framework. The article presents an economy-wide database for analyzing H2-powered aviation. Subsequently the paper highlights three H2 supply pathways provides an exemplary techno-economic cost break-down for ten H2 components and translates them into the data framework. Eight relevant macroeconomic sectors for H2-powered aviation are identified and quantified. Overall the paper contributes on a suitable foundation to apply the macroeconomic dataset to and conduct macroeconomic analyses on H2-powered aviation. Finally the article highlights further research potential on job effects related to future H2 demand.
Methane Cracking as a Bridge Technology to the Hydrogen Economy
Nov 2016
Publication
Shifting the fossil fuel dominated energy system to a sustainable hydrogen economy could mitigate climate change through reduction of greenhouse gas emissions. Because it is estimated that fossil fuels will remain a significant part of our energy system until mid-century bridge technologies which use fossil fuels in an environmentally cleaner way offer an opportunity to reduce the warming impact of continued fossil fuel utilization. Methane cracking is a potential bridge technology during the transition to a sustainable hydrogen economy since it produces hydrogen with zero emissions of carbon dioxide. However methane feedstock obtained from natural gas releases fugitive emissions of methane a potent greenhouse gas that may offset methane cracking benefits. In this work a model exploring the impact of methane cracking implementation in a hydrogen economy is presented and the impact on global emissions of carbon dioxide and methane is explored. The results indicate that the hydrogen economy has the potential to reduce global carbon dioxide equivalent emissions between 0 and 27% when methane leakage from natural gas is relatively low methane cracking is employed to produce hydrogen and a hydrogen fuel cell is applied. This wide range is a result of differences between the scenarios and the CH4 leakage rates used in the scenarios. On the other hand when methane leakage from natural gas is relatively high methane steam reforming is employed to produce hydrogen and an internal combustion engine is applied the hydrogen economy leads to a net increase in global carbon dioxide equivalent emissions between 19 and 27%.
Assessment of Fossil-free Steelmaking Based on Direct Reduction Applying High-temperature Electrolysis
Jun 2021
Publication
Preventing humanity from serious impact of climate crisis requires carbon neutrality across all economic sectors including steel industry. Although fossil-free steelmaking routes receiving increasing attention fundamental process aspects especially approaches towards the improvement of efficiency and flexibility are so far not comprehensively studied. In this paper optimized process concepts allowing for a gradual transition towards fossil-free steelmaking based on the coupling of direct reduction process electric arc furnace and electrolysis are presented. Both a high-temperature and low-temperature electrolysis were modeled and possibilities for the integration into existing infrastructure are discussed. Various schemes for heat integration especially when using high-temperature electrolysis are highlighted and quantified. It is demonstrated that the considered direct reduction-based process concepts allow for a high degree of flexibility in terms of feed gas composition when partially using natural gas as a bridge technology. This allows for an implementation in the near future as well as the possibility of supplying power grid services in a renewable energy system. Furthermore it is shown that an emission reduction potential of up to 97.8% can be achieved with a hydrogen-based process route and 99% with a syngas-based process route respectively provided that renewable electricity is used.
Carbon-Negative Hydrogen Production (HyBECCS) from Organic Waste Materials in Germany: How to Estimate Bioenergy and Greenhouse Gas Mitigation Potential
Nov 2021
Publication
Hydrogen derived from biomass feedstock (biohydrogen) can play a significant role in Germany’s hydrogen economy. However the bioenergy potential and environmental benefits of biohydrogen production are still largely unknown. Additionally there are no uniform evaluation methods present for these emerging technologies. Therefore this paper presents a methodological approach for the evaluation of bioenergy potentials and the attainable environmental impacts of these processes in terms of their carbon footprints. A procedure for determining bioenergy potentials is presented which provides information on the amount of usable energy after conversion when applied. Therefore it elaborates a four-step methodical conduct dealing with available waste materials uncertainties of early-stage processes and calculation aspects. The bioenergy to be generated can result in carbon emission savings by substituting fossil energy carriers as well as in negative emissions by applying biohydrogen production with carbon capture and storage (HyBECCS). Hence a procedure for determining the negative emissions potential is also presented. Moreover the developed approach can also serve as a guideline for decision makers in research industry and politics and might also serve as a basis for further investigations such as implementation strategies or quantification of the benefits of biohydrogen production from organic waste material in Germany
Direct Evidence for Solid-like Hydrogen in a Nanoporous Carbon Hydrogen Storage Material at Supercritical Temperatures
Jul 2015
Publication
Here we report direct physical evidence that confinement of molecular hydrogen (H2) in an optimized nanoporous carbon results in accumulation of hydrogen with characteristics commensurate with solid H2 at temperatures up to 67 K above the liquid vapor critical temperature of bulk H2. This extreme densification is attributed to confinement of H2 molecules in the optimally sized micropores and occurs at pressures as low as 0.02 MPa. The quantities of contained solid-like H2 increased with pressure and were directly evaluated using in situ inelastic neutron scattering and confirmed by analysis of gas sorption isotherms. The demonstration of the existence of solid-like H2 challenges the existing assumption that supercritical hydrogen confined in nanopores has an upper limit of liquid H2 density. Thus this insight offers opportunities for the development of more accurate models for the evaluation and design of nanoporous materials for high capacity adsorptive hydrogen storage.
Cost-optimized Design Point and Operating Strategy of Polymer Electrolyte Membrane Electrolyzers
Nov 2022
Publication
Green hydrogen is a key solution for reducing CO2 emissions in various industrial applications but high production costs continue to hinder its market penetration today. Better competitiveness is linked to lower investment costs and higher efficiency of the conversion technologies among which polymer electrolyte membrane electrolysis seems to be attractive. Although new manufacturing techniques and materials can help achieve these goals a less frequently investigated approach is the optimization of the design point and operating strategy of electrolyzers. This means in particular that the questions of how often a system should be operated and which cell voltage should be applied must be answered. As existing techno-economic models feature gaps which means that these questions cannot be adequately answered a modified model is introduced here. In this model different technical parameters are implemented and correlated to each other in order to simulate the lowest possible levelized cost of hydrogen and extract the required designs and strategies from this. In each case investigated the recommended cost-based cell voltage that should be applied to the system is surprisingly low compared to the assumptions made in previous publications. Depending on the case the cell voltage is in a range between 1.6 V and 1.8 V with an annual operation of 2000e8000 h. The wide range of results clearly indicate how individual the design and operation must be but with efficiency gains of several percent the effect of optimization will be indispensable in the future.
The Role of Hydrogen in a Greenhouse Gas-neutral Energy Supply System in Germany
Sep 2022
Publication
Hydrogen is widely considered to play a pivotal role in successfully transforming the German energy system but the German government’s current “National Hydrogen Strategy” does not specify how hydrogen utilization production storage or distribution will be implemented. Addressing key uncertainties for the German energy system’s path to greenhouse gas-neutrality this paper examines hydrogen in different scenarios. This analysis aims to support the concretization of the German hydrogen strategy. Applying a European energy supply model with strong interactions between the conversion sector and the hydrogen system the analysis focuses on the requirements for geological hydrogen storages and their utilization over the course of a year the positioning of electrolyzers within Germany and the contributions of hydrogen transport networks to balancing supply and demand. Regarding seasonal hydrogen storages the results show that hydrogen storage facilities in the range of 42 TWhH2 to 104 TWhH2 are beneficial to shift high electricity generation volumes from onshore wind in spring and fall to winter periods with lower renewable supply and increased electricity and heat demands. In 2050 the scenario results show electrolyzer capacities between 41 GWel and 75 GWel in Germany. Electrolyzer sites were found to follow the low-cost renewable energy potential and are concentrated on the North Sea and Baltic Sea coasts with their high wind yields. With respect to a hydrogen transport infrastructure there were two robust findings: One a domestic German hydrogen transport network connecting electrolytic hydrogen production sites in northern Germany with hydrogen demand hubs in western and southern Germany is economically efficient. Two connecting Germany to a European hydrogen transport network with interconnection capacities between 18 GWH2 and 58 GWH2 is cost-efficient to meet Germany’s substantial hydrogen demand.
Methanol as a Renewable Energy Carrier: An Assessment of Production and Transportation Costs for Selected Global Locations
Jun 2021
Publication
The importing of renewable energy will be one part of the process of defossilizing the energy systems of countries and regions which are currently heavily dependent on the import of fossil-based energy carriers. This study investigates the possibility of importing renewable methanol comprised of hydrogen and carbon dioxide. Based on a methanol synthesis simulation model the net production costs of methanol are derived as a function of hydrogen and carbon dioxide expenses. These findings enable a comparison of the import costs of methanol and hydrogen. For this the hydrogen production and distribution costs for 2030 as reported in a recent study for four different origin/destination country combinations are considered. With the predicted hydrogen production costs of 1.35–2 €/kg and additional shipping costs methanol can be imported for 370–600 €/t if renewable or process-related carbon dioxide is available at costs of 100 €/t or below in the hydrogen-producing country. Compared to the current fossil market price of approximately 400 €/t renewable methanol could therefore become cost-competitive. Within the range of carbon dioxide prices of 30–100 €/t both hydrogen and methanol exhibit comparable energy-specific import costs of 18–30 €/GJ. Hence the additional costs for upgrading hydrogen to methanol are balanced out by the lower shipping costs of methanol compared to hydrogen. Lastly a comparison for producing methanol in the hydrogen’s origin or destination country indicates that carbon dioxide in the destination country must be 181–228 €/t less expensive than that in the origin country to balance out the more expensive shipping costs for hydrogen.
Spatially-resolved Analysis of the Challenges and Opportunities of Power-to-Gas (PtG) in Baden-Württemberg until 2040
Mar 2017
Publication
The increasing penetration of renewable energies will make new storage technologies indispensable in the future. Power-to-Gas (PtG) is one long-term storage technology that exploits the existing gas infrastructure. However this technology faces technical economic environmental challenges and questions. This contribution presents the final results of a large research project which attempted to address and provide answers to some of these questions for Baden-Württemberg (south west Germany). Three energy scenarios out to 2040 were defined one oriented towards the Integrated Energy and Climate Protection Concept of the Federal State Government and two alternatives. Timely-resolved load profiles for gas and electricity for 2015 2020 2030 and 2040 have been generated at the level of individual municipalities. The profiles include residential and industrial electrical load gas required for heating (conventional and current-controlled CHP) as well as gas and electricity demand for mobility. The installation of rooftop PV-plants and wind power plants is projected based on bottom up cost-potential analyses which account for some social acceptance barriers. Residential load profiles are derived for each municipality. In times with negative residual load the PtG technology could be used to convert electricity into hydrogen or methane. The detailed analysis of four structurally-different model regions delivered quite different results. While in large cities no negative residual load is likely due to the continuously high demand and strong networks rural areas with high potentials for renewables could encounter several thousand hours of negative residual load. A cost-effective operation of PtG would only be possible under favorable conditions including high full load hours a strong reduction in costs and a technical improvement of efficiency. Whilst these conditions are not expected to appear in the short to mid-term but may occur in the long term in energy systems with very high shares of renewable energy sources
Carbon-negative Hydrogen from Biomass Using Gas Switching Integrated Gasification: Techno-economic Assessment
Sep 2022
Publication
Ambitious decarbonization pathways to limit the global temperature rise to well below 2 ◦C will require largescale CO2 removal from the atmosphere. One promising avenue for achieving this goal is hydrogen production from biomass with CO2 capture. The present study investigates the techno-economic prospects of a novel biomass-to-hydrogen process configuration based on the gas switching integrated gasification (GSIG) concept. GSIG applies the gas switching combustion principle to indirectly combust off-gas fuel from the pressure swing adsorption unit in tubular reactors integrated into the gasifier to improve efficiency and CO2 capture. In this study these efficiency gains facilitated a 5% reduction in the levelized cost of hydrogen (LCOH) relative to conventional O2-blown fluidized bed gasification with pre-combustion CO2 capture even though the larger and more complex gasifier cancelled out the capital cost savings from avoiding the air separation and CO2 capture units. The economic assessment also demonstrated that advanced gas treatment using a tar cracker instead of a direct water wash can further reduce the LCOH by 12% and that the CO2 prices in excess of 100 €/ton consistent with ambitious decarbonization pathways will make this negative-emission technology economically highly attractive. Based on these results further research into the GSIG concept to facilitate more efficient utilization of limited biomass resources can be recommended.
No more items...