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Highlights • Techno-economic of a polygeneration for power and DME plant is proposed. • The integration resulted in a production of 103 MW and 2.15 kg/s of DME. • The layout has an energetic and exergetic efficiency of 50% and 44%. • The most expensive equipment resulted in the ASU which accounts for 23%. • Plant produces power & DME at $50/MWh and $18/GJ at carbon tax of $80/tonne of CO 2. Abstract In this paper, we present a novel polygeneration plant with carbon capture for the combined power and dimethyl ether (DME) production. The plant layout integrates a chemical looping CO 2 /H 2 O splitting (CL) unit producing syngas (CO and H 2) for the DME synthesis using the exhaust gases of an oxyfuel power cycle. The primary power is generated by oxy-combustion of syngas generated by the reduction of the metal oxide in the reduction unit of the CL redox cycle with incoming natural gas. The oxyfuel power plant also generates steam for combined power production with two streams Rankine cycles. The aim of the present work is to assess the process on the basis of energy and exergetic efficiency and economic performance of the integrated CL unit for combined power and DME production. The integration proposed resulted in a production of 103 MW e and 185.6 ton/day (2.15 kg/s) of DME. The corresponding energy and exergetic efficiency was 50.2% and 45%, respectively. A discounted cash flow analysis was performed to evaluate the profitability of the process. With a carbon credit of $80/tonne, the plant would be able to meet the current electricity with carbon capture and DME prices of $50/MWh and $18/GJ respectively. The economic analysis provided information on the main economic drivers associated with the high capital investment in the process plant with individual sub-systems. The analysis highlighted the strong potential of integrating chemical looping CO 2 /H 2 O splitting for syngas production into polygeneration systems to increase the overall efficiency while reducing the cost of carbon capture. [ABSTRACT FROM AUTHOR]

Expansion by photovoltaic (PV) technologies in the renewable energy market requires exploring added value integrated with business model innovation. In recent years, a pilot trial of PV water pumping (PVWP) technologies for the conservation of grassland and farmland has been conducted in China. In this paper, we studied the added value of the PVWP technologies with an emphasis on the integration of the value proposition with the operation system and customer segmentation. Using the widely used existing PV business models (PV-roof) as a reference, we evaluated discounted cash flow (DCF) and net present value (NPV) under the scenarios of traditional PV roof, PVWP pilot, PVWP scale-up, and PVWP social network, where further added value via social network was included in the business model. The results show that the integrated PVWP system with social network products significantly improves the performance in areas such as the discounted payback period, internal rate of return (IRR), and return on investment (ROI). We conclude that scenario PVWP social network with business model innovation, can result in value add-ins, new sources of revenue, and market incentives. The paper also suggests that current policy incentives for PV industry are not efficient due to a limited source of revenue, and complex procedures of feed-in tariff verification. [ABSTRACT FROM AUTHOR]

Renewable energies have a key role in defining an energy policy based on security, independence, and sustainability. The Italian market is characterised by the absence of support mechanisms for photovoltaic sources for electricity and by a high level of maturity in the energy market. Consequently, this paper contributes to, and advances, the debate concerning self-consumption that can support the economic sustainability of photovoltaic facilities. We constructed a database to conduct an analysis. A survey was conducted among 750 companies operating in various stages of the industry supply chain. The survey collected data related to industry turnover, profitability levels, profitability margins of the business areas and employee numbers. The economic feasibility of photovoltaic investment is evaluated for systems of varying sizes (3 kW, 20 kW, 200 kW, 400 kW, and 1 MW) located in two areas of the country to account for different levels of insolation (northern and southern regions). The indicators used are net present value (NPV) and discounted payback time (DPBT). A subsequent sensitivity and scenario analysis is conducted according to the share of self-consumption, investment costs, and financial structure to examine 210 case studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal carbonization can readily convert paunch waste to value-added products. • Process modelling indicates that pre-heater and dryer are the main energy consumer. • Hydrothermal carbonization technology development is challenged by reactor high cost. • Treating dewatered paunch waste is more commercially viable despite lower conversion. • Economic viability is highly sensitive to LHSV of reactor and economic assumptions. In this study, dewatered and raw paunch waste, with 15 and 3 wt% total solids respectively, generated at abattoirs was hydrothermally carbonised under subcritical water conditions. Higher solids content was found to produce higher hydrochar yield (i.e. 53% for 15 wt% compared to 33.5% for 3 wt%) at similar operating conditions of 10 bar and 240 °C for 5 min. The morphological differences were noted via Scanning Electron Microscopy (SEM) in the hydrochar samples, and the surface area for processing raw paunch waste was found to be 68.1 m2 g−1 compared to 10.8 m2 g−1 in case of dewatered paunch waste. The light bio-oil was mostly composed of phenolic compounds while the heavy bio-oil mainly contained long chain fatty acids and their esters. Following the experimental work, a full-scale ASPEN Plus process model was developed for a typical abattoir generating 27 tonne dry paunch waste per day. Pre-heater and hydrochar dryer contributed to 73% and 57% of the total energy for processing raw and dewatered paunch waste, respectively, because of the high moisture content of the feedstock and hydrochar. After the equipment sizing and estimation of capital and operating costs, the discounted cash flow analysis was performed using the Nth-Plant financing assumptions. It was concluded that treating dewatered paunch waste is preferable as it: needed a smaller reactor i.e. lower overall initial investment, was less sensitive to bio-oil price, and improved the net present value over a period of 30 years to $2.8 MM. Besides the liquid hourly speed velocity, its commercial viability is highly sensitive to internal rate of return and existence of hydrochar dryer. [ABSTRACT FROM AUTHOR]

• Techno-economic evaluation of H 2 production by APR and SR of glycerol is performed. • Sensitivity analysis, profitability analysis, and risk analysis were accomplished. • TCOP for APR plant is 3.55 $/kgH 2 regarding the equipment purchased costs. • TCOP for SR plant is 3.65 $/kgH 2 regarding the equipment purchased costs. • TCOP mostly influenced by compressor cost, glycerol price, and discount rate. In this paper, a comparative techno-economic evaluation of hydrogen production by glycerol reforming in aqueous and gaseous phases are presented. To accomplish the techno-economic evaluation, firstly the process modeling and design are presented. Based on the equipment purchased costs, with 80 kg/h hydrogen production, the total cost of hydrogen production is estimated 3.65 and 3.55 $/kgH 2 for steam reforming and aqueous phase reforming plants, respectively. Regarding the installation factor in the equipment costs, the total cost of hydrogen production is estimated 7.49 and 7.45 $/kgH 2 for steam reforming and aqueous phase reforming plants, respectively. To investigate the impact of independent parameters and profitability of the proposed plants, sensitivity analysis, cumulative discounted cash flow diagram, net present value, and discounted payback period are introduced. Additionally, to quantify the uncertainties in proposed plants, Monte-Carlo simulation method with ±50% variation of the key influential parameters is applied. Lastly, it is shown that the aqueous phase reforming process is the optimum choice based on the techno-economic evaluation. [ABSTRACT FROM AUTHOR]

• Replacement of PEM water electrolysis with diverse degradation rate was considered. • Cash flow diagram was drawn considering degradation rate of PEM water electrolyzer. • Uncertainty analysis was performed considering renewable energy resources. • Environment impact assessment was carried out in terms of CO 2 emission. • Quantified economic results for H 2 from PEM water electrolysis were provided. An environmental issue such as global warming causing series of disasters has been considered as a serious matter, which asks global cooperation, leading the Paris Agreement. As a result, considerable attention has been paid to H 2 due to utilization and storage of renewable electricity expected to increase as time passes. A polymer membrane electrolyte (PEM) water electrolysis using renewable electricity generating from bioenergy, geothermal, onshore wind, etc., has been introduced to store electricity in form of H 2. For preparing successful H 2 society, an economic analysis was conducted considering PEM water electrolyzer cell replacement and renewable electricity resources to figure out economic feasibility. In this study, profitability analysis by drawing discounted cash flow diagram and uncertainty analysis using Monte-Carlo simulation based on itemized cost estimation result were carried out. The results presented that replacement preferred to occur at 2.20 V of max voltage of the PEM water electrolysis cell if electricity price is low and degradation rate is high. Furthermore, H 2 selling price has been more influential factor to a net present value (NPV) than renewable electricity price and hydro and onshore wind energies are regarded as promising renewable electricity resources to achieve goal of H 2 production cost. Moreover, CO 2 footprint analysis was conducted to provide guidelines on the replacement of PEM water electrolysis in terms of environmental aspect. [ABSTRACT FROM AUTHOR]

• It is more competitive when using coke oven gas than when using hydrogen. • Electricity revenues can further compensate for costs when using coke oven gas. • Producing ethylene from steel-mill off-gases is economically uncompetitive. Utilization of industrial off-gases to produce valuable chemicals has the advantages of reducing dependence on fossil fuels. Despite many studies of off-gas utilization, production of secondary chemicals including detailed kinetic models integrated with a power-generation system to fully utilize byproducts has not been considered. The goal of this study was to techno-economically evaluate a polygeneration system to produce olefins and power from steel-mill off-gases. Two process cases were evaluated; they use carbon monoxide-rich Linz-Donawitz converter gas with either hydrogen or coke oven gas as feed. The hydrogen was concentrated from coke oven gas by using membrane-separation technology. These gases reacted with Linz-Donawitz converter gas to yield methanol, which was then converted to olefins. Kinetic models were applied for methanol synthesis and methanol-to-olefin reaction. Heat exchanger networks are designed to minimize utility usage, and a power generation system that uses the Rankine cycle to fully utilize byproduct stream. Calculated minimum selling prices of ethylene by discounted cash flow analysis were US$ 2030∙tonne−1 when hydrogen was the feed gas, and US$ 1064∙tonne−1 when coke oven gas was the feed gas; both were higher than the current minimum selling price (~US$ 720∙tonne−1) of ethylene derived from naphtha. The reduction in minimum selling price by use of coke oven gas is due to the revenue of power generation from coke oven gas retentate. Linz-Donawitz converter gas production with hydrogen is the most sensitive to feed price, whereas Linz-Donawitz converter gas-with- coke oven gas is the most sensitive to capital investment. The analysis demonstrates that neither system is economically viable under the current condition. The findings of this study represent a basic analysis for future improvements of the off-gas to olefins process, especially highly integrated system with power generation. [ABSTRACT FROM AUTHOR]