Co-production Of Hydrogen Research Articles

Activation of pentose phosphate pathway in Escherichia coli for the co-production of hydrogen and ethanol from glucose

Activation of pentose phosphate pathway in Escherichia coli for the co-production of hydrogen and ethanol from glucose

Co-production of hydrogen and ethanol by pfkA-deficient Escherichia coli with activated pentose-phosphate pathway: reduction of pyruvate accumulation.

BackgroundFermentative hydrogen (H2) production suffers from low carbon-to-H2 yield, to which problem, co-production of ethanol and H2 has been proposed as a solution. For improved co-production of H2 and ethanol, we developed Escherichia coli BW25113 ΔhycA ΔhyaAB ΔhybBC ΔldhA ΔfrdAB Δpta-ackA ΔpfkA (SH8*) and overexpressed Zwf and Gnd, the key enzymes in the pentose-phosphate (PP) pathway (SH8*_ZG). However, the amount of accumulated pyruvate, which was significant (typically 0.20 mol mol−1 glucose), reduced the co-production yield.ResultsIn this study, as a means of reducing pyruvate accumulation and improving co-production of H2 and ethanol, we developed and studied E. coli SH9*_ZG with functional acetate production pathway for conversion of acetyl-CoA to acetate (pta-ackA+). Our results indicated that the presence of the acetate pathway completely eliminated pyruvate accumulation and substantially improved the co-production of H2 and ethanol, enabling yields of 1.88 and 1.40 mol, respectively, from 1 mol glucose. These yields, significantly, are close to the theoretical maximums of 1.67 mol H2 and 1.67 mol ethanol. To better understand the glycolytic flux distribution, glycolytic flux prediction and RT-PCR analyses were performed.ConclusionThe presence of the acetate pathway along with activation of the PP pathway eliminated pyruvate accumulation, thereby significantly improving co-production of H2 and ethanol. Our strategy is applicable to anaerobic production of biofuels and biochemicals, both of which processes demand high NAD(P)H.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-016-0510-5) contains supplementary material, which is available to authorized users.

Co-production of hydrogen and carbon nanotubes on nickel foam via methane catalytic decomposition

The co-production of COx-free hydrogen and carbon nanotubes (CNTs) was achieved on 3-dimensional (3D) macroporous nickel foam (NF) via methane catalytic decomposition (MCD) over nano-Ni catalysts using chemical vapor deposition (CVD) technique. By a simple coating of a NiO–Al2O3 binary mixture sol followed by a drying–calcination–reduction treatment, NF supported composite catalysts (denoted as NiyAlOx/NF) with Al2O3 transition-layer incorporated with well-dispersed nano-Ni catalysts were successfully prepared. The effects of Ni loading, calcination temperature and reaction temperature on the performance for simultaneous production of COx-free hydrogen and CNTs were investigated in detail. Catalysts before and after MCD were characterized by XRD, TPR, SEM, TEM, TG and Raman spectroscopy technology. Results show that increasing Ni loading, lowering calcination temperature and optimizing MCD reaction temperature resulted in high production efficiency of COx-free H2 and carbon, but broader diameter distribution of CNTs. Through detailed parameter optimization, the catalyst with a Ni/Al molar ratio of 0.1, calcination temperature of 550°C and MCD temperature of 650°C was favorable to simultaneously produce COx-free hydrogen with a growth rate as high as 10.3% and CNTs with uniform size on NF.

Perovskite-type oxides LaFe1−xCoxO3 for chemical looping steam methane reforming to syngas and hydrogen co-production

Chemical looping steam methane reforming is a novel technology for syngas and hydrogen production. It’s very important to find suitable oxygen carriers with good reactivity and high agglomeration resistance for this process. In the present work, the perovskite-type oxides LaFe1−xCoxO3 with x=0.1, 0.3, 0.5, 0.7, 1.0 were used as oxygen carriers. The influence of Co doping on the characteristics and the stabilities of these perovskite-type oxides were investigated by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H2-TPR), Brunauer–Emmett–Teller (BET) surface area and fixed-bed experiments. All the as-prepared samples with various Co substitutions exhibited crystalline perovskite structure similar to LaFeO3. The surface adsorbed oxygen which is beneficial to the complete oxidation of CH4 increased as the Co substitution increase. From the point of view of the oxygen-donation ability, resistance to carbon formation, as well as hydrogen generation capacity, the optimal degree of Co substitution is x=0.3. Despite slight sintering, the perovskite-type oxide LaFe0.7Co0.3O3 showed very good regenerability during the twenty redox reactions. In the methane reduction stage, syngas with H2/CO molar ratio close to 2:1 was obtained in the twenty cycles with 85% of CH4 conversion, 43% of CO selectivity, and 50% of H2 selectivity. While in the steam oxidation stage, a steadily hydrogen productivity at about 4mmol/g oxygen carriers was generated.

Co-production of hydrogen and ethanol from glucose by modification of glycolytic pathways in Escherichia coli - from Embden-Meyerhof-Parnas pathway to pentose phosphate pathway.

Hydrogen (H2) production from glucose by dark fermentation suffers from the low yield. As a solution to this problem, co-production of H2 and ethanol, both of which are good biofuels, has been suggested. To this end, using Escherichia coli, activation of pentose phosphate (PP) pathway, which can generate more NADPH than the Embden-Meyhof-Parnas (EMP) pathway, was attempted. Overexpression of two key enzymes in the branch nodes of the glycolytic pathway, Zwf and Gnd, significantly improved the co-production of H2 and ethanol with concomitant reduction of pyruvate secretion. Gene expression analysis and metabolic flux analysis (MFA) showed that, upon overexpression of Zwf and Gnd, glucose assimilation through the PP pathway, compared with that of the EMP or Entner-Doudoroff (ED) pathway, was greatly enhanced. The maximum co-production yields were 1.32 mol H2 mol(-1) glucose and 1.38 mol ethanol mol(-1) glucose, respectively. It is noteworthy that the glycolysis and the amount of NAD(P)H formed under anaerobic conditions could be altered by modifying (the activity of) several key enzymes. Our strategy could be applied for the development of industrial strains for biological production of reduced chemicals and biofuels which suffers from lack of reduced co-factors.

Enhanced Activity of CeO2–ZrO2 Solid Solutions for Chemical-Looping Reforming of Methane via Tuning the Macroporous Structure

Chemical-looping reforming of methane (CLRM) offers a potentially effective approach for the coproduction of syngas and pure hydrogen. Macroporous CeO2–ZrO2 solid solutions with different pore sizes were prepared as oxygen carriers for the CLRM system. The physical and chemical properties of the oxygen carriers were characterized by the techniques of scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), X-ray powder diffraction (XRD), N2 adsorption–desorption, Raman spectra, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), and temperature-programmed oxidation (TPO). The relationship among the structural features, the concentration of oxygen defect, and the oxygen mobility of the macroporous CeO2–ZrO2 solid solutions and the nonporous sample were also discussed. It is found that the specific surface area and oxygen mobility of such oxides are closed correlated to their performance for the CLRM process. Compared with t...

Round-the-clock power supply and a sustainable economy via synergistic integration of solar thermal power and hydrogen processes

We introduce a paradigm-"hydricity"-that involves the coproduction of hydrogen and electricity from solar thermal energy and their judicious use to enable a sustainable economy. We identify and implement synergistic integrations while improving each of the two individual processes. When the proposed integrated process is operated in a standalone, solely power production mode, the resulting solar water power cycle can generate electricity with unprecedented efficiencies of 40-46%. Similarly, in standalone hydrogen mode, pressurized hydrogen is produced at efficiencies approaching ∼50%. In the coproduction mode, the coproduced hydrogen is stored for uninterrupted solar power production. When sunlight is unavailable, we envision that the stored hydrogen is used in a "turbine"-based hydrogen water power (H2WP) cycle with the calculated hydrogen-to-electricity efficiency of 65-70%, which is comparable to the fuel cell efficiencies. The H2WP cycle uses much of the same equipment as the solar water power cycle, reducing capital outlays. The overall sun-to-electricity efficiency of the hydricity process, averaged over a 24-h cycle, is shown to approach ∼35%, which is nearly the efficiency attained by using the best multijunction photovoltaic cells along with batteries. In comparison, our proposed process has the following advantages: (i) It stores energy thermochemically with a two- to threefold higher density, (ii) coproduced hydrogen has alternate uses in transportation/chemical/petrochemical industries, and (iii) unlike batteries, the stored energy does not discharge over time and the storage medium does not degrade with repeated uses.

Effects of Nickel Species on Ni/Al2O3 Catalysts in Carbon Nanotube and Hydrogen Production by Waste Plastic Gasification: Bench- and Pilot-Scale Tests

Upcycling waste plastics into carbon nanotubes (CNTs) and hydrogen is attractive for its efficient disposal. Although Ni-based catalysts are typically used in both hydrogen production and CNT synthesis, few studies have investigated the catalytic active site for the co-production of CNTs and hydrogen by waste plastic gasification. To evaluate the effect of nickel species distribution of the Ni/Al2O3 catalyst, it was prepared by an impregnation method using different calcination atmospheres to determine their feasibility for the co-production of CNTs and hydrogen. For comparison, various Ni/Al2O3 catalysts for CNT growth were examined by CH4 thermal chemical vapor deposition (CVD). Ni/Al2O3 calcined under a reductive H2 atmosphere (H–Ni/Al2O3) gave smaller nickel nanoparticles containing metallic nickel species, which showed optimal performance for CNT and hydrogen co-production by waste plastic gasification. In addition, the quality of the CNTs was higher using this process compared to the CNTs synthesize...

Co-production of hydrogen and carbon nanofibers from catalytic decomposition of methane over LaNi(1−x)Mx O3−α perovskite (where M = Co, Fe and X = 0, 0.2, 0.5, 0.8, 1)

In this work, LaNi(1−x)Mx O3−α (where M = Co, Fe and X = 0, 0.2, 0.5, 0.8, 1) perovskite have been successfully used as catalyst precursors for catalytic decomposition of methane (CDM). LaNi0.8Fe0.2O3−α and LaNi0.8Co0.2O3−α perovskite exhibited better catalytic performance in terms of hydrogen and carbon nanofibers yields during CDM reaction as compared to LaNiO3 perovskite, which can be attributed to the formation of the smaller and more uniform catalyst particles. Moreover, the reduced LaNi(1−x)FexO3−α perovskite also produces filamentous carbons with “chain–like structure” which is different from the filamentous carbons with “tube–like structure” produced from the reduced LaNiO3 and LaNi(1−x)CoxO3−α perovskite. This is due to the different growth mechanisms of those filamentous carbons over the different catalysts. More particularly, chain–like structure filamentous carbons were produced through “pulse–growth mechanism” over the reduced LaNi(1−x)FexO3−α perovskite, whereas tube–like structure filamentous carbons were produced through “smooth–growth mechanism” over the reduced LaNiO3 and LaNi(1−x)CoxO3−α perovskite.

CO2 hydrogenation over cobalt-containing catalysts

Carbon dioxide hydrogenation over catalysts consisting of 0.56–45 wt % cobalt supported on carbon nanotubes (CNTs), carbon nanofibers, few-layer graphite fragments, or CNTs–Al2O3 composites has been investigated. All of the Co/support catalytic systems have been characterized by temperature-programmed reduction, transmission electron microscopy, and scanning electron microscopy. Under the conditions of our catalytic experiment (1 atm, 180–500°C), the CO2 hydrogenation products are CH4 and/or CO and the activity of the catalysts depends on the size and phase state of the cobalt particles. The CNTs-supported materials containing less than 5 wt % Co are catalytically inactive because of the amorphism of the metal. They can be activated by cobalt crystallization by means of heat treatment. The size of the cobalt particles deposited on the carbon supports is about 4 nm. Methods of functionalizing the carbon nanomaterial surface for additional stabilization of metal nanoparticles are suggested.

Co-Synthesis of Hydrogen and Carbon Fuels from Water and Carbon Dioxide

Non-fossil fuel based, low carbon footprint fuels are needed to ameliorate the effects of anthropogenic climate change. We have previously demonstrated molten hydroxide electrolytes for solar water splitting to hydrogen fuel, and molten carbonate electrolytes for solar carbon dioxide splitting to carbon or carbon monoxide fuels. Solid carbon (as coal) is used as the starting point to generate CO and hydrogen for the Fischer-Tropsch generation of a variety of fuels, such as synthetic diesel. However, that process is carbon dioxide emitting intensive. In this study we present the first molten electrolyte sustaining electrolytic co-production of both hydrogen and carbon products in a single cell (1). Here, hydrogen and carbon products are produced without carbon dioxide emissions and instead produced from water and carbon dioxide. The demonstrated functionality of hydroxide and carbonate electrolytes to co-generate hydrogen and carbon fuels at low electrolysis potentials, and from water and CO2starting points, provides a significant step towards the development of renewable fuels. Fang-Fang Li, Shuzhi Liu, Baochen Cui, Jason Lau, Jessica Stuart, Baohui Wang, and Stuart Licht, "A one-pot synthesis of hydrogen and carbon fuels from water and carbon dioxide," recommended for publication Nov. 20, 2014, Advanced Energy Materials Figure 1

Study of CO2 recovery in a carbonate fuel cell tri-generation plant

The possibility of separating and recovering CO2 in a biogas plant that co-produces electricity, hydrogen, and heat is investigated. Exploiting the ability of a molten carbonate fuel cell (MCFC) to concentrate CO2 in the anode exhaust stream reduces the energy consumption and complexity of CO2 separation techniques that would otherwise be required to remove dilute CO2 from combustion exhaust streams. Three potential CO2 concentrating configurations are numerically simulated to evaluate potential CO2 recovery rates: 1) anode oxidation and partial CO2 recirculation, 2) integration with exhaust from an internal combustion engine, and 3) series connection of molten carbonate cathodes initially fed with internal combustion engine (ICE) exhaust. Physical models have been calibrated with data acquired from an operating MCFC tri-generating plant. Results illustrate a high compatibility between hydrogen co-production and CO2 recovery with series connection of molten carbonate systems offering the best results for efficient CO2 recovery. In this case the carbon capture ratio (CCR) exceeds 73% for two systems in series and 90% for 3 MCFC in series. This remarkably high carbon recovery is possible with 1.4 MWe delivered by the ICE system and 0.9 MWe and about 350 kg day−1 of H2 delivered by the three MCFC.

Co-production of hydrogen and carbon nanofibers from methane decomposition over zeolite Y supported Ni catalysts

The objective of this paper is to study the influences of different operating conditions on the hydrogen formation and properties of accumulated carbon from methane decomposition using zeolite Y supported 15% and 30% Ni, respectively, at a temperature range between 500 and 650°C in a pilot scale fixed bed reactor. The temperature ramp was showed a significant impact on the thermo-catalytic decomposition (TCD) of methane. An optimum temperature range of 550–600°C were required to attain the maximum amount of methane conversion and revealed that at 550 and 600°C, catalyst showed longer activity for the whole studied of experimental runs. Additionally, at 550°C, the methane decomposition is two times longer for 30% Ni/Y zeolite than that for 15% Ni/Y zeolite catalyst, whereas it is almost three times higher at 500°C. A maximum carbon yield of 614.25 and 157.54gc/gNi were reported after end of the complete reaction at 600°C with 30% and 15% Ni/Y zeolite catalyst, respectively. From BET, TPD, and XRD analysis, we had reported that how the chemistry between the TCD of methane and metal content of the catalysts could significantly affect the hydrogen production as well as carbon nano-fibers. TEM analysis ensured that the produced carbon had fishbone type structures with a hollow core and grew from crystallites of Ni anchored on the external surface of the catalysts and irrespective of the metal loadings, the whisker types of nano filaments were formed as confirmed from FESEM analysis. Nevertheless, the effect of volume hourly space velocity (VHSV) on the methane conversion was also investigated and reported that the methane conversion increased as VHSV and nickel concentration in Ni–Y catalysts increased. Additionally, the initial methane decomposition rate increases with VHSV and it has reverse and non-linear relevancy to the weight of Ni/Y zeolite catalyst.

Influence of metal addition to Ni-based catalysts for the co-production of carbon nanotubes and hydrogen from the thermal processing of waste polypropylene

This paper investigates the co-production of hydrogen and carbon nanotubes from the pyrolysis–catalytic gasification of waste plastics (polypropylene). We report on the influence of a range of metal additions to a nickel based catalyst based on ternary mixed oxide types Ni–Metal–Al, where the metal was Zn, Mg, Ca, Ce or Mn. The results showed that of the different metal–nickel catalysts investigated, the Ni–Mn–Al catalyst was the most promising catalyst in relation to the co-production of hydrogen and CNT. For example, the Ni–Mn–Al catalyst produced 71.4mmolhydrogeng−1 plastic, while the hydrogen production using Ni–Ca–Al, Ni–Ce–Al and Ni–Zn–Al catalysts were 68.5mmolg−1, 63.1mmolg−1 and 45.9mmolhydrogeng−1 plastic respectively. In addition, carbon deposition on the catalyst was highest in the order of: Ni–Mn–Al>Ni–Ca–Al>Ni–Zn–Al>Ni–Ce–Al>Ni–Mg–Al. The carbon deposition for the Ni–Mn–Al catalyst was found to consist of mostly carbon nanotubes. Further investigation of the Ni–Mn–Al catalyst demonstrated that the interaction between Ni and catalyst support plays a significant role in the gasification process; weak metal support interaction (for the Ni–Mn–Al catalyst calcined at 300°C) resulted in a lower hydrogen production and much higher yield of carbon products. In addition, the influence of steam injection rate on hydrogen and carbon nanotube production was investigated for the Ni–Mn–Al catalyst. Increasing the steam injection rate significantly increased hydrogen production and decreased carbon deposition. However, at lower steam injection rates, the quality of the product carbon nanotubes was improved.

Characteristic of macroporous CeO2-ZrO2 oxygen carrier for chemical-looping steam methane reforming

Chemical-looping steam methane reforming (CL-SMR) is a novel process towards the production of pure hydrogen and syngas, consisting of a syngas production reaction and a hydrogen production reaction. Macroporous CeO2-ZrO2 oxygen carriers with different pore sizes prepared by colloidal crystal templating method and characterized by techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and temperature programmed reduction (H2-TPR) were tested in CL-SMR process. For comparison, nonporous CeO2-ZrO2 oxygen carrier prepared by precipitation method was also investigated. It was found that macroporous CeO2-ZrO2 oxygen carriers owned higher reducibility and reactivity in CL-SMR process than nonporous samples. For the macroporous CeO2-ZrO2 sample, the decline of pore size could improve the reducibility and reactivity. The macroporous sample with a pore size of 100 nm (labeled as Ce-Zr-100) showed the highest performance for the co-production of syngas and hydrogen during the successive CL-SMR redox cycles. After 10 redox cycles, it still retained good porous structure and reducibility. It was found that the porous structure could accelerate the oxygen release from bulk to surface, leading to a good mobility of oxygen and higher reducibility. In addition, it was also favorable for diffusion and penetration of methane and water steam into the sample particles to accelerate the reaction rate.

Energy and exergy analyses of a solar driven Mg–Cl hybrid thermochemical cycle for co-production of power and hydrogen

Analysis and performance assessment of a solar driven hydrogen production plant running on an Mg–Cl cycle, are conducted through energy and exergy methods. The proposed system consists of (a) a concentrating solar power cycle with thermal energy storage, (b) a steam power plant with reheating and regeneration, and (c) a hybrid thermochemical Mg–Cl hydrogen production cycle. The results show that higher steam to magnesium molar ratios are required for full yield of reactants at the hydrolysis step. This ratio even increases at low temperatures, although lowering the highest temperatures appears to be more favorable for linking such a cycle to lower temperature energy sources. Reducing the maximum cycle temperature decreases the plant energy and exergy efficiencies and may cause some undesirable reactions and effects. The overall system energy and exergy efficiencies are found to be 18.8% and 19.9%, respectively, by considering a solar heat input. These efficiencies are improved to 26.9% and 40.7% when the heat absorbed by the molten salt is considered and used as a main energy input to the system. The highest exergy destruction rate occurs in the solar field which accounts for 79% of total exergy destruction of the integrated system.

Metabolic engineering of Escherichia coli strains for co-production of hydrogen and ethanol from glucose

The co-production of H2 and ethanol from glucose was studied to address the low H2 production yield in dark fermentation. Several mutant strains devoid of ackA-pta, pfkA or pgi were developed using Escherichia coli BW25113 ΔhycA ΔhyaAB ΔhybBC ΔldhA ΔfrdAB as base strain. Disruption of ackA-pta eliminated acetate production during glucose fermentation but resulted in the secretion of a significant amount of pyruvate (0.73 mol mol−1 glucose) without improving the co-production of H2 and ethanol. When pfkA or pgi was further disrupted to enhance NAD(P)H supply by diverting the carbon flux from Embden-Meyerhof-Parnas (EMP) pathway to the pentose phosphate pathway (PPP), the cell growth of both strains was severely impaired under anaerobic conditions, and only the ΔpfkA mutant could recover its growth after adaptive evolution. The production yields of the ΔpfkA strain (H2, 1.03 mol mol−1 glucose and ethanol, 1.04 mol mol−1 glucose) were higher than those of the pfkA+ strain (H2, 0.69 mol mol−1 glucose and ethanol, 0.95 mol mol−1 glucose), but pyruvate excretion was not reduced. The excessive excretion of pyruvate in the ΔpfkA mutant was attributed to an insufficient NAD(P)H supply caused by the diversion of carbon flux from the EMP pathway to the Entner-Doudoroff pathway (EDP), rather than the PPP as intended. This study suggests that co-production of H2 and ethanol from glucose is possible, but further metabolic pathway engineering is required to fully activate PPP under anaerobic conditions.

Hydrogen production from methane and solar energy – Process evaluations and comparison studies

Three conventional and novel hydrogen and liquid fuel production schemes, i.e. steam methane reforming (SMR), solar SMR, and hybrid solar-redox processes are investigated in the current study. H2 (and liquid fuel) productivity, energy conversion efficiency, and associated CO2 emissions are evaluated based on a consistent set of process conditions and assumptions. The conventional SMR is estimated to be 68.7% efficient (HHV) with 90% CO2 capture. Integration of solar energy with methane in solar SMR and hybrid solar-redox processes is estimated to result in up to 85% reduction in life-cycle CO2 emission for hydrogen production as well as 99–122% methane to fuel conversion efficiency. Compared to the reforming-based schemes, the hybrid solar-redox process offers flexibility and 6.5–8% higher equivalent efficiency for liquid fuel and hydrogen co-production. While a number of operational parameters such as solar absorption efficiency, steam to methane ratio, operating pressure, and steam conversion can affect the process performances, solar energy integrated methane conversion processes have the potential to be efficient and environmentally friendly for hydrogen (and liquid fuel) production.

Chemical-looping steam methane reforming over macroporous CeO2–ZrO2 solid solution: Effect of calcination temperature

Chemical-looping steam methane reforming (CL-SMR) is a novel process for the co-production of pure hydrogen and syngas without purification processes. A series of CeO2–ZrO2 mixed oxides were prepared by colloidal crystal templating method with calcination temperature increasing from 450 to 850 °C. The structural characteristic and reducibility of CeO2–ZrO2 oxygen carriers were investigated by SEM, XRD and TPR techniques and correlated to their reactivity for CL-SMR. The CeO2–ZrO2 mixed oxides calcined at low temperatures (e.g., 450 °C) exhibit a better uniform and three-dimensionally ordered macroporous structure, which enhance the mobility of oxygen species, improving the reducibility of CeO2–ZrO2 oxygen carriers. The ordered macroporous structure can lead to a high reactivity for CL-SMR, especially for the hydrogen production in water splitting reaction. It was found that the Ce–Zr-450 sample showed the best performance for H2 production. After ten redox CL-SMR cycles at 800 °C, the Ce–Zr-450 sample still maintained relatively high hydrogen yield and the three-dimensionally ordered macroporous structure remained in good condition, indicating high reactivity and structural stability.

Membrane technology embedded into IGCC plants with CO2 capture: An economic performance evaluation under uncertainty

An economic performance assessment framework has been developed for membrane reactor modules embedded into Integrated Gasification Combined Cycle (IGCC) power plants with CO2 capture (IGCC-MR), recognizing that such an option offers a promising prospect of significant environmental performance enhancement as well as a technical pathway for the co-production of electricity and hydrogen. A functional Net Present Value (NPV) model has been developed first to evaluate the economic viability of IGCC-MR plants. The project value of IGCC-MR is compared to other competing technology options such as Supercritical Pulverized Coal-fired and traditional IGCC power plants with and without CO2 capture. Sources of irreducible uncertainty (market and regulatory) as well as technology risks are explicitly recognized and the effect of these uncertainty drivers on the plant's/project's value is taken into account using Monte-Carlo techniques. Therefore, more realistic distribution profiles of the plant's economic performance outcomes are generated rather than single-point value estimates. It is shown that future regulatory action on CO2 emissions could induce appealing NPV-distribution profiles for IGCC-MR in the presence of uncertainty and technology risks. Finally, a creatively structured portfolio of technology-push and/or market-pull policy incentives could lead to more attractive profiles, suggesting possible means for accelerating the realization of demonstration projects.