Reduction In Capital Cost Research Articles

European offshore wind capital cost trends up to 2020

Offshore wind capacity has increased significantly over the past decade with 16 GW installed by the end of 2017. Offshore wind technologies present an effective tool for EU countries to address their renewable production targets, as extensive areas of high winds are available offshore. However, offshore wind is not yet cost competitive in European electricity markets, and frequently requires support schemes to finance extensive capital cost requirements. Therefore, capital cost reductions are critical to make offshore wind technologies competitive in the market. Here, a benchmark tool to analyze capital expenditure trends associated with offshore wind implementation in Europe up to 2020 is provided. A database of all existing farms was developed, detailing more than 21 GW of already commissioned or consented capacity, and trends were described using multiple linear regression models. Results indicate that following a consistent rise from 2000 to 2015, capital costs have since begun to decline. The impact of several farm parameters such as turbine capacity, average farm depth or farm location on the capital expenditures have been estimated.

Manufacturing competitiveness analysis for hydrogen refueling stations

Fuel cell electric vehicles (FCEVs) have now entered the market as zero-emission vehicles. Original equipment manufacturers such as Toyota, Honda, and Hyundai have released commercial cars in parallel with efforts focusing on the development of hydrogen refueling infrastructure to support new FCEV fleets. Persistent challenges for FCEVs include high initial vehicle cost and the availability of hydrogen stations to support FCEV fleets. This study sheds light on the factors that drive manufacturing competitiveness of the principal systems in hydrogen refueling stations, including compressors, storage tanks, precoolers, and dispensers. To explore major cost drivers and investigate possible cost reduction areas, bottom-up manufacturing cost models were developed for these systems. Results from these manufacturing cost models show there is substantial room for cost reductions through economies of scale, as fixed costs can be spread over more units. Results also show that purchasing larger quantities of commodity and purchased parts can drive significant cost reductions. Intuitively, these cost reductions will be reflected in lower hydrogen fuel prices. A simple cost analysis shows there is some room for cost reduction in the manufacturing cost of the hydrogen refueling station systems, which could reach 35% or more when achieving production rates of more than 100 units per year. We estimated the potential cost reduction in hydrogen compression, storage and dispensing as a result of capital cost reduction to reach 5% or more when hydrogen refueling station systems are produced at scale.

Multi-stage stochastic optimization framework for power generation system planning integrating hybrid uncertainty modelling

In this paper, a multi-stage stochastic optimization (MSO) method is proposed for determining the medium to long term power generation mix under uncertain energy demand, fuel prices (coal, natural gas and oil) and, capital cost of renewable energy technologies. The uncertainty of future demand and capital cost reduction is modelled by means of a scenario tree configuration, whereas the uncertainty of fuel prices is approached through Monte Carlo simulation. Global environmental concerns have rendered essential not only the satisfaction of the energy demand at the least cost but also the mitigation of the environmental impact of the power generation system. As such, renewable energy penetration, CO2,eq mitigation targets, and fuel diversity are imposed through a set of constraints to align the power generation mix in accordance to the sustainability targets. The model is, then, applied to the Indonesian power generation system context and results are derived for three cases: Least Cost option, Policy Compliance option and Green Energy Policy option. The resulting optimum power generation mixes, discounted total cost, carbon emissions and renewable share are discussed for the planning horizon between 2016 and 2030.

Optimal Sizing and Power Sharing of Distributed Hybrid Renewable Energy Systems Considering Socio-Demographic Factors

When sizing distributed hybrid renewable energy systems (HRESs) it has been found that capital costs can significantly be reduced when socio-demographic factors are considered. Unique electricity usage patterns have previously been classified using users’ socio-demographic factors and used to optimize the size of individual stand-alone HRESs. An optimization model is formulated where an individual HRES is assigned to each of the six socio-demographic classifications and power sharing is implemented with neighboring sites in a specific configuration. Solving the optimization problem with a hybrid approach using Matlab’s genetic algorithm and fmincon results in an 82,10% reduction in capital costs compared to the system without power sharing.

Optimization and analysis for palm oil mill operations via input-output optimization model

A typical palm oil mill produces crude palm oil, crude palm kernel oil and other biomass from fresh fruit bunches. While the milling process is well established in the industry, insufficient research and development has been done on analyzing the operational performance of a mill. Factors such as operating time and fruit availability affect the performance of a palm oil mill (e.g., capital, operating and labor costs). This paper presents an input-output model to optimize the operations of a palm oil mill based on maximum economic performance. Following this, feasible operating range analysis (FORA) is performed to study the utilization and flexibility of the process. A palm oil mill case study in Malaysia is used to illustrate the proposed approach. Based on the optimized results, it was found that 37% reduction in capital cost and 49% increase in economic performance is achieved. Meanwhile, the utilization index of the mill during peak season increases from 0.48 to 0.76.

Regulatory reform of energy and economic growth in Japan

Deregulation of the electric power business began in the middle of the 1990s in Japan, and after several law revisions, the electric power market was fully liberalized in April 2016. On the other hand, the Japanese government has also adopted the FIT system, which gives incentives for introducing renewable energy power, as a means for reducing greenhouse gas emissions in 2012. In this paper, we take up regulatory changes involving deregulation and global warming countermeasures, analyze the facts and impact, identify the problems that appear as side effects, and consider the impact on economic growth. The conclusion obtained is as follows. Deregulation has certainly stimulated the power market and has provided new entrants, new price menus and value-added services. Especially in the latter half of the 1990s and early 2000s, electricity prices declined, and productivity measured by TFP improved. The price cut was due to the reduction of capital costs by the existing dominant electric power companies, although after the Lehman shock in 2008, neither price reduction nor productivity improvement can be confirmed. Meanwhile, the FIT has played a role in expanding renewable energy power. However, it not only raised the cost of electricity but also became a factor impairing the stability of the entire power supply. Japan’s electricity supply system is shifting to a stage where additional measures for stable supply are required.

Sustainable Water Resources Using Corner Pivot Lateral, A Novel Sprinkler Irrigation System Layout for Small Scale Farms

Sprinkler irrigation systems are widely used in medium and large scale farms in different forms. However less types are available to apply in small farms due to their high costs. The current study was done according to a novel cost effective design for a semi-permanent sprinkler irrigation system for small farm owners. The new layout known as Corner Pivot Lateral (CPL) was examined in irrigation test center at Lijian Scientific and Technological Demonstration Park, at Nanning city, China. CPL was implemented without a main/sub mainline pipe, by applying a single pivoting lateral at the corner of the plot that directly connected to the resource to convey water from the pump. The lateral moves around the corner using a rotating elbow in a quadrant pattern manually to cover the entire farm. A conventional semi-permanent system was applied for the same farm as reference. A cost analysis on the required components as well as annual operational costs was carried out for comparison and control. Results showed that a lower system component would be needed for the CPL method. Overall, more than a 15% capital cost reduction with 7% annual cost decrement was achieved for CPL in this experiment comparatively. The Catch can technique was applied to examine the CPL system’s efficiency and 79% water distribution uniformity around the sprinkler was obtained. This new method can encourage small estate holders to switch from traditional to pressurized systems which optimizes water application costs.

High penetration renewable generation within Australian isolated and remote power systems

Remote communities increasingly integrate renewable source generation to reduce the environmental and economic impact of diesel generation. Despite benefits scaling proportionally with the level of renewable penetration, most systems restrict renewable utilisation to below 30% of annual production. Identifying system complexity as a key barrier to renewable uptake, this paper investigates methodologies to simplify integration of high renewable penetrations. Three approaches are considered, via three Australian case studies; King Island, Tasmania (approach one), Flinders Island, Tasmania (approach two), and Rottnest Island, Western Australia (approach three). Approach one details a methodology for wind plus storage integration. Approach two details a methodology for wind, solar PV, plus storage integration. Approach three details a methodology for wind and solar PV integration, without storage. All approaches facilitate high renewable penetrations, with each island majority renewable supplied. Approach one benchmarks system performance, with King Island one of the worlds’ earliest high penetration renewable islands. Approach two explores benefit via renewable diversification. Approach three investigates rationalisation of energy storage via low load diesel and demand management technology substitution. For approach three a 32% reduction in capital cost was observed, identifying commercial justification for the approach via deferral of energy storage integration.

Dual Completion Petroleum Production Engineering for Several Oil Formations

Abstract Cost-efficient, enabling technologies for keeping and increasing the reservoir recovery rate of oil-formations with high water cut of produced fluids and exhausted resource are really essential. One of the easiest but short-term ways to increase oil production and incomes at development of oil deposits is cost of development and capital cost reduction. Therefore, optimal choice and proper feasibility study on the facilities for multilayer oil fields development, especially at the late stage of reservoir working, is a crucial issue for now-day oil industry. Currently, the main oil pools do not reach the design point of coefficient of oil recovery. The basic feature of the late stage of reservoir working is the progressing man-made impact on productive reservoir because of water injection increasing for maintaining reservoir pressure. Hence cost-efficient, enabling technologies for keeping and increasing the reservoir recovery rate of oil-formations with high water cut of produced fluids and exhausted resource are really essential. To address the above concerns the dual completion petroleum production engineering was proposed. The intensity of dual completion of formation with of different permeability is determined by rational choice of each of them. The neglect of this principle results a disproportionately rate of highly permeable formations development for the time. In effect the permeability of the formations or their flow rate is decreasing. The problem is aggravated by lack of awareness of mechanics of layers' mutual interference in producers and injectors. Dual completion experience in Russian has shown, that success and efficiency of the technology in many respects depend on engineering support. One of the sufficient criteria for the choice of operational objects should be maximal involvement of oil-saturated layers by oil displacement from seams over the economic life of well producing oil. If it is about getting high rate of oil recovery for irregular formations there is no alternative to dual completion and production. The recommended dual completion petroleum production technology enables development several formations by single well at the time. The dual completion petroleum production technology has been more important than ever because it is right not only for formations but for thin layers with undeveloped remaining reserves.

An assessment of the impacts of renewable and conventional electricity supply on the cost and value of power-to-gas

Power-to-gas (P2G) is a promising enabling technology for more cross-sector integration but its high cost has so far been a key barrier to implementation. Electricity supply is the greatest contributor to the levelised cost therefore it is important to understand which technologies and strategies can minimise the cost and accelerate the deployment. In this study, a method is devised to evaluate the cost and value of combined systems comprising P2G and renewable energy technologies such as solar photovoltaics, wind and hydro as well as comparing to traditional electricity supply via the wholesale market. The proposed models are based on a temporal resolution of 1 h and include partial operation and ageing throughout the system's lifespan. Our analysis covers both distributed and centralised P2G systems producing hydrogen or methane as well as various value-adding services across different geographies. It is found that the capacity factor of a P2G system drives the economic case and therefore the electricity supply from hydropower plants is economically more attractive than electricity from wind and solar photovoltaic plants in this order. Under today's market conditions, it is highly advisable to combine local renewable supply with wholesale-based supply but interestingly, a 20% capital cost reduction in wind technology or a P2G system efficiency of 80% are break-even points for P2G systems producing hydrogen and connected to wind plants.

Economic viability of multiple algal biorefining pathways and the impact of public policies

This study presents an extensive systems-level multi-pathway sustainability assessment of algae biofuel production that demonstrates the necessity of high-value co-products, examines the impact of public policy scenarios, and identifies improvements and pathway directions required for economic viability. Engineering process models for several fuel and co-product pathways were leveraged to perform high fidelity techno-economic analysis. These pathways included: baseline hydrothermal liquefaction; protein extraction followed by hydrothermal liquefaction; fractionation into high-value chemicals with fermentation followed by hydrothermal liquefaction for fuels; and a small-scale first-of-a-kind plant coupled with a wastewater treatment facility. From these models, it was shown that hydrothermal liquefaction as a fuel-only pathway is not economically viable. Likewise, the benefits of coupling with wastewater water treatment are insignificant compared to the impact of reduced facility size resulting in increased capital costs. These models were also used to examine public policy scenarios, uniquely presenting their impact on the breakeven cost of fuel production and sensitivity to scenario assumptions. Specifically, depreciation type was shown to be irrelevant for writeoffs faster than 10 years. Due to discounting, short-term subsidies were found to capture 50% of the subsidy value in 6 years with an additional 24 years required for full subsidy valuation. Integration of a carbon economy was shown to decrease biofuel production costs, particularly for the protein pathway due to the co-product accounting. Finally, a metric of normalized costs was used to compare algal biorefineries to corn and cellulosic ethanol production, showing that algal systems are uniquely different due to significantly higher capital costs, though operational costs are comparable. This work demonstrates that, to reach economic viability, algal biofuel production must either utilize higher value non-fuel co-products or achieve drastic reductions in capital costs.

Short Review on Porous Metal Membranes-Fabrication, Commercial Products, and Applications.

Porous metal membranes have recently received increasing attention, and significant progress has been made in their preparation and characterisation. This progress has stimulated research in their applications in a number of key industries including wastewater treatment, dairy processing, wineries, and biofuel purification. This review examines recent significant progress in porous metal membranes including novel fabrication concepts and applications that have been reported in open literature or obtained in our laboratories. The advantages and disadvantages of the different membrane fabrication methods were presented in light of improving the properties of current membrane materials for targeted applications. Sintering of particles is one of the main approaches that has been used for the fabrication of commercial porous metal membranes, and it has great advantages for the fabrication of hollow fibre metal membranes. However, sintering processes usually result in large pores (e.g., >1 µm). So far, porous metal membranes have been mainly used for the filtration of liquids to remove the solid particles. For porous metal membranes to be more widely used across a number of separation applications, particularly for water applications, further work needs to focus on the development of smaller pore (e.g., sub-micron) metal membranes and the significant reduction of capital and maintenance costs.

An efficient integrated trigeneration system for the production of dual temperature cooling and fresh water: Thermoeconomic analysis and optimization

This paper describes and analyzes an integrated trigeneration system for the production of air conditioning, fresh water and refrigeration at different temperatures. A single effect steam driven H2O-LiBr absorption cooling (ABC) cycle is integrated with a multi effect distillation (MED) unit and a CO2 based parallel compression economization-vapor compression refrigeration (PCE-VCR) cycle. The thermo-economic analysis is performed to identify how the integration can improve the energy utilization and annual costs. A detailed parametric study of several key design and operating parameters and an economic optimization are also conducted. The analysis shows that the MED plant can produce a significant amount of fresh water using the free steam supplied by the ABC cycle. Changes in the number of effects, top and last effect brine temperatures, size of the VCR cycle and number of operating hours significantly impact the MED plant productivity and unit production cost of water (UPCW). The integrated ABC-MED-VCR system, in a base case analysis, reduces the unit production cost of cooling (UPCC) for combined cooling and refrigeration and the UPCW by 25% and 27%, respectively compared to separate use of the three systems. Due to integration, substantial improvements in the fuel energy utilization and reductions in the annual capital cost (ACC) and annual operating cost (AOC) are achieved. Also, the AOC and ACC decrease 38% and 13%, respectively. At the optimized conditions, utilization of exhaust waste gas to drive the integrated ABC-MED-VCR system leads to additional 52%, 41% and 0.13% reductions in the AOC, UPCC and UPCW, respectively.

ПРОТОЧНЫЙ БИОРЕАКТОР ДЛЯ ИССЛЕДОВАНИЯ БАКТЕРИАЛЬНО-ХИМИЧЕСКОГО ВЫЩЕЛАЧИВАНИЯ СУЛЬФИДНЫХ МЕДНО-НИКЕЛЕВЫХ РУД И КОНЦЕНТРАТОВ

Бактериально-химическое выщелачивание металлов зарекомендовало себя как альтернативная технология гидрометаллургической переработки и обогащения рудного сырья благодаря снижению капитальных затрат и вредного воздействия на окружающую среду. Различные технологические схемы биовыщелачивания успешно применяются для переработки сульфидных концентратов, бедных сульфидных и окисленных руд. Одной из важнейших задач дальнейшего развития данной отрасли биотехнологии является усовершенствование биореакторных установок (в частности – проточного типа), снабжение их системами дополнительного контроля технологических параметров. В статье кратко освещены основные результаты, полученные в НИГТЦ ДВО РАН в рамках исследований биовыщелачивания сульфидной кобальт-медно-никелевой руды. Приведено описание биореактора для исследования биовыщелачивания в периодическом режиме и реакторной установки каскадного типа для исследования биовыщелачивания в непрерывном режиме. Представлена модель усовершенствованного биореактора для бактериально-химического выщелачивания сульфидной руды. Приведено подробное описание микроконтроллерного способа управления технологическими параметрами. Область применения представленных результатов – лабораторные, укрупненные и полупромышленные испытания технологии чанового и реакторного бактериально-химического выщелачивания сульфидных руд.

A comparative study of novel activated AMP using 1,5-diamino-2-methylpentane vs MEA solution for CO2 capture from gas-fired power plant

Bench-scale pilot plant study of AMP and 1,5-diamino-2-methylpentane (DA2MP) blend for CO2 capture from gas-fired power plant is investigated. The concentration of the amine blend is 2 kmol/m3 AMP-1.5 kmol/m3 DA2MP while that of single solvent MEA is 5 kmol/m3. Comparative analysis was based on CO2 absorption efficiency (%), absorber mass transfer coefficient (KGav(ave), kmol/kPa h m3), desorber mass transfer coefficient (KLav, h−1), rich amine loading (αrich, mol CO2/mol amine), lean amine loading (αlean, mol CO2/mol amine), cyclic loading (CL, mol CO2/mol amine), cyclic capacity (CC, mol CO2/L-amine soln.), CO2 absorption rate (rabs, g-CO2/h), and regeneration energy (Qreg, GJ/tonne CO2). The contribution of sensible energy (Qsen, GJ/tonne CO2), vaporization energy (Qvap, GJ/tonne CO2), and desorption heat (ΔHdes, GJ/tonne CO2) towards Qreg was also investigated. Results showed that the AMP-DA2MP blend possess higher KGav(ave) (11.66%), KLav (7.67% higher), and CO2 absorption efficiency (4.66% higher) than MEA. Also, the superior cyclic loading (51.5%) and cyclic capacity (6.7%), and lower regeneration energy (13.8% lower) was observed for the AMP-DA2MP blend. The desorption heat (ΔHdes) was the major contributor to the Qreg of both amine systems however the ΔHdes of AMP-DA2MP was 23% lower than MEA. It was noticed that though the water concentration of the amine blend (60.7 wt%) is lower than MEA (70 wt%), the vaporization energy of the amine blend was 32.9% higher than MEA. Therefore, besides the amount of water concentration, higher desorber temperature profile, amine solvent vapor pressure and boiling point also increases the vaporization energy. The results is a revelation of possible reduction in capital cost and operating costs for the AMP-DA2MP blend compared to the standard MEA.

Highly Efficient and Robust One Dimensional (1D) Transition Metal Oxide Based Nanostructured Electrocatalyst Architectures for Acid Mediated Oxygen Evolution Reaction (OER)

The huge consumption of conventional fossil fuels for meeting the energy demand has led to major unsustainable environmental concerns; warranting the identification and development of clean and non-carbonaceous energy sources1, 2. In this aspect, hydrogen has been well-known as a clean, non-carbonaceous and potential future energy source with superior energy density than currently adopted carbonaceous energy sources1, 3. However, efficient and economic production along with cost-effective storage and distribution of hydrogen utilizing clean non-carbonaceous approach is of paramount importance before universal adoption of hydrogen as a clean energy source in the impending non-carbonaceous fuel economy2. Along these lines, electricity driven water splitting is considered as a frontrunner for hydrogen production4, 5. However, commercial development of water electrolysis has witnessed major obstacles due to the need for expensive platinum group metals (PGM) based electro-catalysts (Pt, RuO2, IrO2) which exhibit excellent electro-catalytic activity and stability for kinetically sluggish oxygen evolution reaction (OER) in acid assisted proton exchange membrane (PEM) based water electrolysis that has major advantages. Therefore, the identification and development of novel and ultra-low noble metal or noble metal free electro-catalysts exhibiting excellent electro-catalytic activity and superior long term electrochemical stability in highly acidic operating conditions of OER, will aid in the reduction of capital cost of water electrolysis cells(~$2/KgH2) and thus, augmenting the progression towards successful commercialization1. Thus, aiming at this goal for the significant improvement in the OER kinetics and also to achieve the superior electro-catalytic activity towards OER, tailoring of the material length scale to one-dimensional (1D) architecture is one of the most promising catalyst development strategies. Over the past few years, electro-catalysts with 1D nanostructured morphologies such as nanowires (NWs), nanorods (NRs) as well as nanotubes (NTs) have garnered significant attention as potentially effective materials for water splitting due their inherent benefits 6. Therefore, in the present study, based on our theoretical first principles calculations of the total energies and electronic structures, we have explored the generation of 1D nano structured-morphology (Fig.1) of the earth abundant F substituted transition metal oxide based powder electrocatalyst system. The as-synthesized electrocatalyst system exhibits remarkably higher electro-catalytic activity and excellent stability for acidic OER. The as-synthesized 1D electrocatalyst exhibited significantly lower charge transfer resistance (Rct) than benchmark noble metal based OER catalysts and many other precious/non-precious electrocatalysts systems. In addition, the as-synthesized 1D electrocatalyst displayed remarkable activity and approached a current density of ~ 10 mA/cm2 at an overpotential of ~ 200 mV. In summary, we have synthesized high performance, robust 1D ultra low noble metal containing OER electrocatalyst system for PEM water splitting. The enhanced electrocatalytic activity of this electro-catalyst is majorly attributed to the modification of electronic structure and lower charge transfer resistance (i.e. lower activation polarization owing to 1D architecture). Thus, we believe that the present architecture of the electrocatalyst system is indeed promising and reliable for the cost-effective and sustainable hydrogen production. The results of this work will be presented and discussed. Acknowledgements: Financial support of NSF-CBET grant# 1511390, Edward R. Weidlein Chair Professorship funds and the Center for Complex Engineered Multifunctional Materials (CCEMM) is acknowledged.

Counterfactual comparisons of investment options for wind power and agricultural production in the United States: Lessons from Northern Ohio

We analyze potential efficiency gains in wind power projects by comparing counterfactual investment decisions in two different scenarios under a real options framework. The first scenario is a standard wind power investment, where the investor rents the land from local farms. In the second scenario, the wind power investor buys the land and commercializes both electricity and crop production, thus reducing the revenue risk through the diversification. Both scenarios have a waiting option, with the wholesale prices leading the installation decision. We model the electricity price as a mean reverting process with jumps and with different jumping probabilities for the different seasons of the year. Corn prices follow a mean reverting process. The waiting flexibility was modeled as a bundle of European options. The results indicate that the waiting option is exercised in 100% of our simulations in both scenarios, suggesting the still important role of government policies to stimulate wind power. More importantly, in more than 90% of the simulations, the second scenario brought value to the investment. Furthermore, net present values are more sensitive to reductions in capital costs than electricity prices. These results can form the basis for more effective policies for the wind power sector.

Clock Hand Lateral, A New Layout for Semi-Permanent Sprinkler Irrigation System

The experiment was done based on a new layout for a semi-permanent set-move sprinkler irrigation system with a lower capital and annual cost requirement. In this work, a center-pivot system layout was applied to set up a semi-permanent system with a hand-move lateral. The clock hand lateral (CHL) sprinkler irrigation system was implemented using a shorter mainline length with a smaller diameter, lesser number of lateral pipes, minimum number of fittings and a single valve outlet. This combination offers an affordable irrigation system with minimizing the required components. The new irrigation system design was examined at the Agricultural Academy of Science experiment farm at Guangxi, China. The sprinkler system mainline pipe directly extended from the water resource to the center of the plot to feed a single lateral, connected through a pivot elbow. The lateral was rotating around the plot manually, the same way as clock hands do. An ordinary set-move split lateral for the same plot was designed for comparison and control. Based on results, a 37.5% capital cost reduction with an 11.2% annual cost decrement was obtained for CHL compared to the set-move semi-permanent. Water application depth was measured via distribution uniformity coefficient (DU) examination, using a catch can method. The low quarter DU for CHL was counted for 86%.

Robust Initialization of Rigorous Process Simulations of Multiple Dividing Wall Columns via Vmin Diagrams

Dividing Wall Columns (DWCs) allow the separation of a ternary mixture in one column shell by applying a vertical partition wall, yielding a reduction of operational and capital costs of up to 30%. Multiple DWC (mDWC), the consequent advancement of standard DWC, makes use of more than one partitioning wall, allowing the separation of quaternary or even higher mixtures in one column shell accompanied by a further reduction of energy consumption. Since no dedicated models for these columns are available in commercial process simulators, thermodynamic consistent flowsheets have to be designed and implemented. The thermally fully coupled Petlyuk arrangement is one important example. However, the initial convergence of these substituting flowsheets is demanding, since a large number of meaningful initial guesses have to be provided. A promising method for generating these first estimates are minimum vapor (Vmin) diagrams. All internal flows can be extracted from these diagrams and used for robust initialization of the simulation. The goal of this work is to present the Vmin method in a comprehensive way in order to initialize mDWC simulations to predict the separation of four component mixtures. Additionally, the adaptation of the diagram to configurations different than Petlyuk arrangements for mDWC is evaluated and a systematic procedure to obtain them is presented. In the end, an example of a converging simulation is given, which was obtained with the values from the Vmin diagram.

Ultra-Low Platinum Group Metal (PGM) Containing (Mn1-XIrx)O2:10F - Highly Active and Durable Oxygen Evolution Electrocatalyst for PEM Water Electrolysis

The generation of clean and sustainable hydrogen via advantageous proton exchange membrane (PEM) based water electrolysis is hitherto considered as one of the most efficient and reliable technologies among all other conventional hydrogen production approaches1. However, commercial development of this technology has been largely constrained due to the need for highly expensive and environmentally scarce platinum group metal (PGM) based electro-catalysts such as Pt, RuO2, and IrO2 which exhibit excellent electro-catalytic performance towards energy intensive and sluggish oxygen evolution reaction (OER) in PEM water electrolysis2, 3. Therefore, identification, synthesis and development of novel reduced noble metal containing electro-catalysts, exhibiting remarkable electro-catalytic activity and robust long term electrochemical stability similar/superior to state-of-the art OER electro-catalyst - IrO2 in highly acidic operating conditions of OER is highly desirable. This will lead to capital cost reduction of PEM water electrolyzer cells creating a path towards commercialization. In line with this objective, utilizing theoretical first principles approaches, we have engineered anionic fluorine (F) doped solid solution of MnO2 and IrO2, denoted as (Mn1-xIrx)O2:10F (x=0.2, 0.3, 0.4) as an efficient OER electrocatalyst system, exhibiting lower onset potential and higher current density than the state-of-the art IrO2 and other previously reported systems for PEM water electrolysis4. The electrochemical characterization of the as-prepared electro-catalysts has been carried out in a three-electrode configuration system, using 1N sulfuric acid (H2SO4) solution as a proton source as well as the electrolyte. As shown in Fig. 1 (a), the as-synthesized electro-catalysts (Mn1-xIrx)O2:10F (x=0.2, 0.3 and 0.4) demonstrate notable electro-catalytic performance with a lowest reported onset potential to date of ~ 1.35 V (vs. NHE), ~ 80 mV lower than that of IrO2 ( ~1.43 V vs. NHE). The (Mn1-xIrx)O2:10F (x=0.2, 0.3 and 0.4) electro-catalysts also exhibit superior electro-catalytic activity (measured at ~1.45 V vs. NHE) i.e. ~ 15 fold higher current density (for x = 0.3 and 0.4) compared to the standard IrO2 (Fig. 1a). This superior electrochemical performance of as-prepared (Mn1-xIrx)O2:10F electro-catalysts is attributed to the lower charge transfer resistance (Rct, determined from the diameter of the semi-circle in the low frequency region of the EIS plot, Fig. 1b) and beneficial electronic structure modification upon the introduction and generation of F-doped solid solution. In addition, chronoamperometry tests conducted in 1N H2SO4 solution at ~1.45 V (vs. NHE) for 24 hours displayed minimal loss in current density, indicating good electrochemical stability of the as-prepared electro-catalyst. In summary, the present electro-catalyst system with ~80% reduction in noble metal content, displays significantly much higher electro-catalytic performance than the state-of-the art IrO2, suggesting the favorable reduction in the overall capital cost of PEM based water electrolyzer and thus, contributing to efficient and economic hydrogen production. Results of these studies will be presented and discussed.