Techno-economic Feasibility Analysis Research Articles

Comparative Analysis of Hybrid Renewable Energy Systems for Off-Grid Applications in Chad

In this study, a techno-economic feasibility analysis of hybrid renewable energy systems for four household categories in rural areas of Chad was studied based on the multi-criteria assessment technique. The problem of this study is to know the best optimal solution in the technical and economic feasibility study of the decentralized mini-grids for the rural electrification of isolated villages in Chad. The main objective of the work is to assess technically, economically and environmentally the feasibility of six scenarios of hybrid systems in five isolated sites in Chad. The performance analysis involved six scenarios of possible hybrid solutions while achieving a supply-demand balance for sustainable electrification of the remote villages, using the HOMER software. The results have shown that the optimum combination of the hybrid system was the photovoltaic/battery system with a Net Present Cost (NPC) of US $ 328,146 and it was found at Etena village. The photovoltaic/Wind/Diesel/Battery hybrid configuration was the least optimum system and it has appeared in Mandelia village. In terms of energy cost, the lowest Levelized Cost of Energy (LCOE) was estimated at US $ 0.236/kWh in a photovoltaic/Wind/Battery configuration at Koundoul site and the highest costs US $ 0.363/kWh in the photovoltaic/Battery configuration at the Linia site. It is established that hybrid solutions can be developed to make electricity available and accessible to the population of the remote rural areas in Chad. However, it is imperative that the local government must subsidize the diesel price to promote the adaptation of the abundant renewable solutions.

Analysis of Potential and Feasibility of Hydropower Energy from Sepaku Semoi Dam in Penajam Paser Utara Regency

This paper will present a techno-economic potential and feasibility analysis in the planning of renewable hydropower energy from Sepaku Semoi Dam in Penajam Paser Utara (PPU) Regency. The dam was planned to be built to support the water needs of Indonesia’s prospective capital. The analysis was done based on the last twenty years’ rainfall intensity data history from Sepaku rain station and Sepinggan rain station and digital elevation model (DEM) from DEMNAS with support of the river basin agency of Kalimantan Timur. The result of dependable discharge calculation of Sepaku Semoi river using FJ Mock Method is 2.45 m/s2. And the head of the hydropower power plant is 15.85 meters. The total potential electricity generated from hydropower reached 2,593,140 kWh/year. The assessment of feasibility indicators in this research took into account the technology and economic aspects. The technology aspects help evaluate the technical planning of installations that are possible to build in the dam. The economic aspect of feasibility evaluates the net present value (NPV), internal rate of return (IRR), and the payback period of renewable energy installation. This analysis aimed to get a comprehensive insight from the potential hydropower energy that exists at the research locations and conduct a feasibility study based on techno-economic analysis to develop renewable energy. The results showed that 15.85 meters had the most significant potential of hydropower by generating 290 kW continuous power with a feed-in tariff of 0.054 USD/kWh. The electricity was feasible to offer to the government electrical company. Moreover, this project had a payback period of 8 years, and NPV of 64,005 USD, and an IRR Project of 11.86%.

Energy consumption, environmental performance, and techno-economic feasibility analysis of the biomass-to-hydrogen process with and without carbon capture and storage

Owing to the negative environmental impact and safety problems of fossil fuel resources, chemical processes based on renewable energy have been extensively studied for further development. In this study, the thermodynamic, economic, and environmental performances of biomass-to-hydrogen (BTH) conversion were assessed using corn straw as a raw material. Further, the process used to achieve BTH conversion with/without carbon capture and storage (CCS) was evaluated and analyzed in this study. According to the simulation results, the economic and environmental properties of BTH processes using different CO2 capture rates were evaluated via thermodynamics and life cycle assessment. Compared with the biomass hydrogen production process without CCS, the EC of the BTH process with CCS decreased by 17%. However, the total investment and production cost of biomass hydrogen production with CCS increased by 1.3% and 14.6–19.4%, respectively. The energy efficiency of BTH conversion with CCS was 17% lower than that of BTH conversion without CCS. Further, the payback period of the BTH process performed with CCS was approximately 5–6 years. According to the energy consumption and the economic and environmental performances, BTH conversion with a CO2 capture rate of 80% is a appropriate CCS system for CO2 capture. The life cycle assessment of BTH conversion demonstrates that the BTH system with CCS can result in negative greenhouse gas emissions. The development of the BTH process using CCS is thus of great significance for achieving carbon neutralization.

Experimental and techno-economic feasibility analysis of renewable energy technologies for Jabel Ali Port in UAE

Due to the excessive amount of exhaust gas emitted by its activities, the seaport is considered to be one of the sources of the deterioration of the marine environment. In addition, most seaports rely on the National Grid as an energy source to meet domestic and ship power needs. However, nowadays, the maritime industry requires an environmentally-friendly operation of seaports. This paper presents a summary discussion of the concept of green ports and some of their aspects. It further offers a bird-eye view of some of their applications worldwide. Meanwhile, an initiative is made to attempt applying renewable energy power sources to a selected case-study; “Port of Jabel Ali”, to examine the feasibility of applying such aspects of the green port concept to this port. A prototype experiment is setup to assess the wind and solar potential in the region, aided with a simulation model using HOMER™ software, to verify the experimental results and to confirm the principle. Results show that the three selected cases show promising performances while applying the renewable energy application through the maritime port with the main grid. When the solar PV system is applied to the system, a total cost reduction of 10% is achieved as well as a 10.5% reduction in levelized cost of energy. When the wind farm system is applied, 20.8% cost reduction with corresponding 21% lower levelized cost of energy is achieved. Therefore, the wind farm and solar PV system achieve 28.7% cost reduction and 31.8% reduction of the levelized cost of energy.

Enhancing Disinfection of Contaminated Natural Water Using 40 kHz Frequency Cavitational Reactor

Natural water quality is continuously diminishing with human intervention and poses a major threat to the ecosystem. The present work investigated the treatment of contaminated lake water using a 40 kHz frequency cavitational reactor. The total colony count present in raw water was 1,300 ± 150 CFU with initial chemical oxygen demand (COD) of 100 ± 30 mg/L. The synergy of cavitation with a catalyst (titanium dioxide [TiO2]) and ozonation was studied. The comparative performance was analyzed by comparing individual and synergic effects. The combined effects of a catalyst with cavitation have shown the maximum removal of the microbial count and COD. Techno-economic feasibility analysis confirmed that the synergy of a catalyst with cavitation results in the maximum reduction in microbial count and COD. The percentage removal of coliform such as Enterobacter, Salmonella, and Escherichia coli (catalyst concentration: 25.0 μM/L and treatment time: 20 min) was 90.8, 92.6, and 100, respectively, with COD removal of 71.6%. Enhanced results may be obtained due to an increase in the cavitational effect in the presence of a solid catalyst. The synergy of cavitation with TiO2 enhanced the microbial removal rate by 45.8% compared to the individual effect. Investigation confirms that synergy effects produced from ultrasound and catalyst were highly beneficial for reducing microbial count from raw water with a substantial COD reduction.

Solar energy for air conditioning of an office building in a case study: Techno-economic feasibility assessment

Global electricity consumption is continuing to grow at a faster pace over the past few years. Electricity is used most often in buildings and in the growing demand for appliances and air conditioners. Basic strategies to minimize energy consumption include implementing energy efficiency measures and adopting renewable energy. Photovoltaics in particular has received considerable attention. Thus, this paper presents the detailed techno-economic feasibility analysis and environmental utility of a solar PV powered air conditioner system for an office building. The design, simulation and optimization of the system were performed using HOMER software. The system performance analysis was performed using various criteria such as Total Net Present Cost (TNPC), Cost of Energy (CoE), Renewable Fraction (RF) and CO2 emission analysis as objective functions. Energy purchased from the grid, energy sales, net energy purchases, and grid interactions were also analyzed. The simulation results reveal that the values of TNPC, CoE and RF are 2277.61 $, 0.0655 $/kWh and 79.2%, respectively. The total system generation is estimated to be 2875 kWh, of which 80.5% (2315 kWh) comes from PV and 19.5% from the grid. The system reports a grid energy purchase, energy sales and net energy purchase of 559 kWh, 1094 kWh and −534.11 kWh, respectively. The air conditioner's energy demand is fully met at 100%, records 0% unmet load and capacity shortage, and an excess energy of 73.5 kWh. The total annual CO2 emission mitigated is 1459.548 kg, a savings of 36488.7 kg (40.22 tons) is achieved over the system project lifetime.

Towards zero energy solar households – A model-based simulation and optimization analysis for a humid subtropical climate

Energy conservation and efficiency in the residential building sector is an important field to control carbon emissions worldwide. Solar energy integration in domestic buildings decreases the grid dependency and carbon emissions. This paper investigates techno-economic feasibility, energy, exergy, and life cycle emissions analysis of solar energy integration to achieve an annual net-zero energy balance for a household. A local survey is carried out in the regions of Pakistan to define the representative building structure, services, and schedules. A representative household is then analyzed. TRNSYS is used for modelling and annual transient simulation of household thermal load and energy systems. TRNSYS-GenOpt co-simulations determine the optimal insulation thickness of the building envelope to minimize the thermal load. The on-site renewable energy supply system consists of solar PV, solar space heating, solar domestic hot water generation, and solar absorption cooling. The envelope insulation results in a 37.2% reduction in annual thermal load. Solar PV system supplies 93.4% of annual electricity demand. Solar collectors provide hot water during winter and thermal comfort during 92.4% of air conditioning hours. Energy and exergy analyses are used to evaluate the thermal performance of solar PV, thermal collectors, and absorption system. The life cycle cost analysis performed for a conventional and the proposed building shows that the net present value of the zero-energy solar household (ZESH) becomes lower than that of the conventional household in 8 years. Also, the life cycle emissions are calculated for conventional and ZESH. The CO2 emissions of ZESH are only 8.7% of that of a conventional household. This study reveals that a ZESH is technically as well as economically viable in humid subtropical climate regions.

Analysis of hybrid solar biomass power plant for generation of electric power

The need of world electricity production is growing at an increasing rate and because of its limited supply, it cannot completely be met by ordinary energy framework. The use of hybrid systems by renewable electricity sources for energy generation has also created considerations in general. There is no one source of renewables ready to continuously load electricity, and hybrid systems are thus a key solution. Renewable energy is produced by inexhaustible reserves, usually refilled on a human scale, such as sun, wind, hydro, mainstay, biomass, etc. In four core areas, renewable energy often provides energy: electricity, air and water heating/cooling, transport, and rural (stand-alone and network) energy services. In comparison with other sources, renewable power sources have reserves in large geographical regions amassed in a small number of countries. Rapid organization of renewable energy sources and energy conservation brings enormous energy stability, ecological change relief and financial benefits. Hybrid systems (PV-Biomass) are used in different regions to provide electricity to overcome discontinuity and transition in solar and wind power. This paper discusses the techno-economic feasibility analysis of solar biomass system in the Ludhiana district of Punjab.

A Techno-Economic Feasibility Analysis of Renewable Energy-Based Marine Micro-Grid for Cruise Ship Applications: A Case Study Simulation

Abstract This article mainly deals with the design and developments of marine micro-grid for cruise ship applications. The incorporations of the solar PV array with existing fossil-fuel‐based generators and the replacement of an engine-based propulsion system into the electric propulsion system have shown enormous improvements in the technical performance and optimal operations of the system. The proposed hybrid marine micro-grid (HMMG) system design and development has created more influences on the system investment flows and environmental pollutant mitigation. Here, the hybrid micro-grid model has been developed with necessary multi-objective functions and operating constraints. The optimum techno-economic feasibility analysis has been carried out with an energy-balanced loss of load probability algorithm, which proved that the planned energy management system has a highly commendable and efficient configuration to achieve good system performance with viable economics for a sustainable energy society.

Quantification on fuel cell degradation and techno-economic analysis of a hydrogen-based grid-interactive residential energy sharing network with fuel-cell-powered vehicles

Hydrogen-based (H2-based) interactive energy networks for buildings and transportations provide novel solutions for carbon-neutrality transition, regional energy flexibility and independence on fossil fuel consumption, where vehicle fuel cells are key components for H2-electricity conversion and clean power supply. However, due to the complexity in thermodynamic working environments and frequent on/off operations, the proton exchange membrane fuel cells (PEMFCs) suffer from performance degradation, depending on cabin heat balance and power requirements, and the ignorance of the degradation may lead to the performance overestimation. In order to quantify fuel cell degradation in both daily cruise and vehicle-to-grid (V2G) interactions, this study firstly proposes a two-space cabin thermal model to quantify the ambient temperature of vehicle PEMFCs and the power supply from PEMFCs to vehicle HVAC systems. Afterwards, a stack voltage model is proposed to quantify the fuel cell degradation for multiple purposes, such as daily transportation and V2G interactions. Afterwards, the two models are coupled in a community-level based building-vehicle energy network, consisting of twenty single residential buildings, rooftop PV systems, four hydrogen vehicles (HVs), a H2 station, community-served micro power grid, local main power grid, and local H2 pipelines, located in California, U.S.A. Comparative analysis with and without fuel cell degradation is conducted to study the impact of dynamic fuel cell degradation on the energy flexibility and operating cost. Furthermore, a parametrical analysis is conducted on the integrated HV quantity and the grid feed-in tariff to reach trade-off strategies between associated fuel cell degradation costs and grid import cost savings. The results indicate that, in the proposed hydrogen-based building-vehicle energy network, the total fuel cell degradation is 3.16% per vehicle within one year, where 2.50% and 0.66% are caused by daily transportation and V2G interactions, respectively. Furthermore, in the H2-based residential community, the total fuel cell degradation cost is US$6945.2, accounting for 33.4% of the total operating cost at $20770.61. The sensitivity analysis results showed that, when the HV quantity increases to twenty, the fuel cell degradation of each HV decreases to 2.50%, whereas the total fuel cell degradation cost increases to 42.8% of the total operating cost. Last but not the least, the cost saving by V2G interactions can compensate the fuel cell degradation cost when the grid feed-in tariff is reduced by 40%. Research results can provide basic modelling tools on dynamic fuel cell degradation, in respect to vehicle power supply, vehicle HVAC and V2G interactions, together with techno-economic feasibility analysis, paving path for the development of hydrogen energy for the carbon-neutrality transition.

A Technoeconomic Feasibility Analysis for Affordable Energy System in the East African Community Countries

Access to energy is among the key pillars to socioeconomic and improved life style. The East African Community (EAC) countries, also members of sub-Saharan Africa, are among countries with enough energy resources but still struggling with low electricity access, and the lower proportion of citizens with electricity access challenges such as expensive tariff, frequent blackouts, and unreliable service still persists. Diesel technology is among the easy and fast installation technologies for a location with an urgent need of electricity while solar is a clean technology with free fuel. Considering the diversity of electricity tariffs, cost of diesel fuel, and suitability to solar energy exploitation in EAC, this paper intends to provide a technoeconomic analysis for reliable, affordable, and sustainable energy system in the region. A daily load of 94.44 kWh recorded from averaging electricity bills of a luxury house in Kigali, Rwanda, is used as research object, and HOMER simulations are carried on considering the level of such daily load being supplied by either (a) diesel generator, (b) solar + diesel technology, (c) PV + battery storage, or (d) PV + battery storage + grid system in each member country of the EAC. The results show that (a) solar energy is a feasible and applicable technology for energy generation for the whole six EAC countries; (b) for South Sudan, if it is a standalone system, the diesel technology is less costly than solar technology; however, solar energy can still be recommended to be adopted as it has no gas emissions; (c) except South Sudan, PV + battery storage technology is found to be more affordable and cleaner than any technology including diesel; and (d) the option of connecting PV + battery storage to the grid is found more economical for locations where grid interaction is possible because their levelized electricity costs (LCOE) are lower than the real electricity tariffs currently in use within each of the six EAC countries. The solar energy system with battery storage (both off-grid and grid connected) proposed in this research can lead to an efficient increase of national energy resource exploitation in the EAC countries, resulting in reliable, affordable, and sustainable energy access to all the citizenry of the EAC.

Techno-economic feasibility analysis of a eucalyptus-based power plant using woodchips

Forest biomass plays a critical role in developing countries, with high potential to contribute to the energy needs as a cheaper and carbon-friendly alternative. In Brazil, eucalyptus plantations have gained attention in recent years as a promising source for the power sector. Aiming to assess this potential, this work analyzed the techno-economic feasibility of a eucalyptus woodchip-based power plant. A typical 10 MW power plant was modeled using empirical parameters based on the Steam Rankine Cycle. Woodchip samples were collected and energy properties, fuel demand, eucalyptus area required and unit variable cost were determined. In economic analysis, NEWAVE (Long and Medium Term Interconnected Hydrothermal Systems Operation Planning Model) and ANAFIN (Financial Analysis Model for Electrical Projects), both developed by CEPEL (Brazilian Electrical Research Center) were used for the first time to analyze forest biomass projects taking into account fuel availability and hydrological risks. Three energy trading scenarios were evaluated: (1) full commercialization in Brazilian regulated market, (2) full in free market and (3) partial in both markets. Results showed that 4,200 ha of eucalyptus plantations would be needed to ensure sustainable woodchip supply. Moisture content, basic density and woodchip price played an essential role in determining future costs. All scenarios of energy trading were economic feasible, and scenario (3) mitigated energy spot price risk and might be considered the effective risk-return strategy. The simulated strategies may improve decision makers visibility over the risk-return relation of a eucalyptus power plant. This methodology may be used to evaluate new forest biomass energy projects in potential areas. This study will help encourage bioenergy and power diversification in developing countries.

Renewable energy integration/techno-economic feasibility analysis, cost/benefit impact on islanded and grid-connected operations: A case study

On-grid and off-grid renewable energy sources have emerged as a more efficient way to meet large-scale urban and rural needs. The integration of renewables into the utilities/island mode as well as into the techno-economic feasibility studies determines the financial viability, technical and operational viability of the project. This study was conducted to integrate renewables and techno-economic feasibility analysis using the utility grid-connected and islanded mode to meet the demand for community and commercial loads with these strategic objectives. Three main analytical tasks have been performed, including: optimization, simulation, and sensitivity analysis. We selected four sensitivity cases and further divided each sensitivity case into four sensitivity loops, including different combinations of renewable energy sources, e.g., photovoltaics, wind turbines, battery banks, power grids, converters, and diesel generators. The following parameters were used to conduct a techno-economic feasibility analysis: capital costs, replacement costs, operating and maintenance costs, salvage costs, fuel costs, real-time commercial/community load, and climate data. The best results of sensitivity case-2 were selected for the techno-economic feasibility analysis of the remaining four sensitivity cases. The islanded mode net present and annualized sensitivity loop-1 costs in sensitivity case-2 were noted at $1381080.42 and $106832.62, respectively. Net present and annualized sensitivity loop-1 costs in sensitivity case-2 of the grid-connected utility mode were noted at $512792.1 and $39,666.71, respectively. The proposed utility grid-connected mode cost is two times lower than that of the islanded mode, so we have chosen sensitive case-2 for hourly, seasonal, and annual electrical load flow and techno-economic feasibility analysis to meet the community and commercial load demand.

Sustainable offshore oil and gas fields development: Techno-economic feasibility analysis of wind–hydrogen–natural gas nexus

Offshore oil and gas field development consumes quantities of electricity, which is usually provided by gas turbines. In order to alleviate the emission reduction pressure and the increasing pressure of energy saving, governments of the world have been promoting the reform of oil and gas fields for years. Nowadays, environmentally friendly alternatives to provide electricity are hotspots, such as the integration of traditional energy and renewable energy. However, the determination of system with great environmental and economic benefits is still controversial. This paper proposed a wind–hydrogen–natural gas nexus (WHNGN) system for sustainable offshore oil and gas fields development. Combining the optimization model with the techno-economic evaluation model, a comprehensive evaluation framework is established for techno-economic feasibility analysis. In addition to WHNGN system, another two systems are designed for comparison, including the traditional energy supply (TES) system and wind–natural gas nexus (WNGN) system. An offshore production platforms in Bohai Bay in China is taken as a case, and the results indicate that: (i) WNGN and WHNGN systems have significant economic benefits, total investment is decreased by 5,190 and 5,020 million $ respectively, and the WHNGN system increases 4,174 million $ profit; (ii) WNGN and WHNGN systems have significant environmental benefits, annual carbon emission is decreased by 15 and 40.2 million kg respectively; (iii) the system can be ranked by economic benefits as follows: WHNGN>WNGN>TES; and (iV) the WHNGN system is more advantageous in areas with high hydrogen and natural gas sales prices, such as China, Kazakhstan, Turkey, India, Malaysia and Indonesia.

Green hydrogen enrichment with carbon membrane processes: Techno-economic feasibility and sensitivity analysis

Biohydrogen production from biomass through dark fermentation provides a great potential to achieve a green hydrogen economy for sustainable energy development. However, the purification of fermentative biohydrogen usually contains 30–40 vol% CO2 at small-scale plants requires advanced separation technologies. Carbon molecular sieving membranes are considered as an alternative solution in this application. This work focuses on the techno-economic feasibility analysis of H2-selective carbon membrane systems for biohydrogen enrichment by investigation of process design, optimization of operating parameters, and the selection of membrane materials. High vacuum operation on the permeate is favorable to reduce the specific cost as the membrane-related capital cost is dominating the total cost. While the operation with feed gas compression provides better separation performance, and the minimum specific cost of $ 0.026/Nm3 at 6 bar was identified to achieve the hydrogen recovery of 90%. A two-stage carbon membrane system is technically feasible to reach the biohydrogen purity of >99.5 vol% with the specific cost of $ 0.06/Nm3, which is lower than pressure swing adsorption. The sensitivity analysis indicates that the carbon membrane system is scalable and flexible in responding to the variation of plant capacity with the feed flow ranges from 500 to 2500 Nm3/h without significant changes in production cost. Compared to the enhancement of membrane selectivity, improving hydrogen permeance by developing submicrometer asymmetric carbon membranes is urgently needed to increase its competitiveness for biohydrogen purification.

THE OUTLOOK DIGITAL INDOOR ADVERTISING IN MINI-MARKET USING TECHNO ECONOMY ANALYSIS: IMPLEMENTATION IN INDONESIA

R esearch Aims: This paper wants to confirm the process feasibility study and advantage application when technology in social media enters goods' commercialisation . Design/methodology/approach: The methodology used in this research qualitative research methodologies, with an approach to data analysis using techno-economic and collective data on digital indoor advertising . Research Findings: The results of techno-economic analysis and feasibility analysis explaining digital indoor advertising business in Indonesia mini market is declared worthy of running, with description NPV on cash flows Rp. 3,664,679,991 and NPV sensitivity analysis of Rp. 3,554,930,887, IRR of 14.09%, and 13.96% (sensitivity analysis). Theoretical Contribution/Originality: This research contributes to the growth rate of digital advertising usage in Indonesia by viewing and measuring the business feasibility relating to the products used and looking at the profit and loss projects for the company when willing to run the business based on the techno-economic analysis . Practitioner/Policy Implications : This study intended as a reference and recommendation for promoting a product through a feasibility study, which tailors to the advantages implementation of digital indoor advertising mini-market in Indonesia. Especially for management/managers, product promotion becomes a strategy that has to play to catch up and develop market segmentation of a product. Research limitation & i mplications: The implementation needs business feasibility in determining effective or not promoting a product through techno-economic analysis . Digital advertising, which placed in a mini-market, can potentially lift the branding of a product in the marketing function.

Techno-economic feasibility analysis of a 3-kW PV system installation in Nepal

This study investigates the techno-economic feasibility of installing a 3-kilowatt-peak (kWp) photovoltaic (PV) system in Kathmandu, Nepal. The study also analyses the importance of scaling up the share of solar energy to contribute to the country's overall energy generation mix. The technical viability of the designed PV system is assessed using PVsyst and Meteonorm simulation software. The performance indicators adopted in our study are the electric energy output, performance ratio, and the economic returns including the levelised cost and the net present value of energy production. The key parameters used in simulations are site-specific meteorological data, solar irradiance, PV capacity factor, and the price of electricity. The achieved PV system efficiency and the performance ratio are 17% and 84%, respectively. The demand–supply gap has been estimated assuming the load profile of a typical household in Kathmandu under the enhanced use of electric appliances. Our results show that the 3-kWp PV system can generate 100% of electricity consumed by a typical residential household in Kathmandu. The calculated levelised cost of energy for the PV system considered is 0.06 $/kWh, and the corresponding rate of investment is 87%. The payback period is estimated to be 8.6 years. The installation of the designed solar PV system could save 10.33 tons of CO2 emission over its lifetime. Overall, the PV systems with 3 kWp capacity appear to be a viable solution to secure a sufficient amount of electricity for most households in Kathmandu city.

Techno-economic and environmental feasibility analysis of rice husks fired energy system for application in a cluster of rice mills

The agro-processing industries can play a critical role in the development of sustainable and clean energy systems. The lack of knowledge about the technical and economic viability of agro-waste to energy is a major barrier to the successful implementation of such energy systems in developing countries, especially sub-Saharan Africa countries. This paper presents the techno-economic-environmental assessment of a cluster of rice mills located in Abakaliki, Nigeria, as a provider of clean energy. The cluster of rice mills can sustainably fulfil its energy needs through the application of organic Rankine cycle based combined heat and power plant fired by rice husks. Three scenarios of the plant were proposed and investigated for complete information. The rice husk from the cluster can provide daily 20–30 MWh and 4–91 MWh of electrical power and thermal power, respectively, at 14.5–21% efficiency. A tonne of rice husk can provide 0.45–0.65 MWh of electricity; that the unit cost of electricity from the proposed system is between 0.12 and 0.159$/kWh, which is better than 0.947 US$/kWh for the diesel generator currently in use. About 270–483 kg of CO2/MWh can be saved by the proposed combined heat and power system in relation to the current use of Lister diesel generators. The proposed plant has the potentials to support the Nigerian Nationally Determined Contributions to the Paris Agreement. The work also presents an appropriate business model and policy pathway for sustainable cottage rice processing industries.

CFD Simulations for Performance Enhancement of a Solar Chimney Power Plant (SCPP) and Techno-Economic Feasibility for a 5 MW SCPP in an Indian Context

The use of solar energy for power generation using the innovative solar chimney concept has been explored by many researchers mostly with the help of analytical models as well as CFD simulations while experimental studies for a pilot and bench scale facilities have been carried out. The efficiencies of these chimneys, however, are less than 1% (~0.07% for 50 kW pilot plant similar to Manzanares plant in Spain). In the present study, an effort has been made to make modifications in the chimney design to improve the efficiency of the chimney in terms of power generation. CFD simulations have been carried out for this modified design and the efficiency is seen to improve to 0.12% for a 50 kW chimney. Furthermore, a techno-economic feasibility analysis has been carried out for a conventional 5 MW solar power plant which can be installed on the western part of India, which receives good solar irradiation throughout the year. Two cases with and without government subsidies have been considered. It is observed that a high rate of return (~20.4%) is obtained for a selling price of electricity of Rs 5 per kWh with government subsidy, while a rate of return of ~19% is obtained for Rs 10 per kWh without government subsidy.

In situ cultivation of aromatic plant species for the phytomanagement of an aged-trace element polluted soil: Plant biomass improvement options and techno-economic assessment of the essential oil production channel

Due to the presence of trace element (TE) in agricultural soils, wide areas are unproper for food production and the clean-up of soil is not a feasible option. Considering the potential remediation options, the use of aromatic plants producing a high quantity of biomass and developing high-added value sectors such as essential oil (EO) production could be valuable regarding one of the phytomanagement objectives, i.e. the restoration of an economic activity. The purpose of this study was hence to evaluate in situ the suitability of two aromatic crops, clary sage and coriander, for the phytomanagement of aged TE-polluted soils, taking into account plants' growth, development and biomass production, essential oil (EO) content and quality as well as a techno-economic feasibility analysis of the channel. In situ experiments have been carried out on two agricultural plots of 1.5 ha, a TE-polluted one (Pb: 394 ppm - Zn: 443 ppm - Cd: 7.2 ppm) and an unpolluted one (Pb: 22 ppm - Zn: 48 ppm - Cd: 0.4 ppm). Our findings have shown the ability of coriander and sage to grow similarly on both unpolluted and TE-polluted soil and to produce significant amounts of biomass. The pesticide residue and TE analyses have demonstrated that the EO only contained trace amounts of the contaminants, below or close to the limit of quantification of the method used and similar to marketed products. Mycorrhizal inoculation has also shown promising results by increasing the colonization rates of both aromatic plants, but did not result in higher biomass or EO amounts. Our study brings new evidence towards the potential of clary sage to be used for the phytomanagement of TE-polluted areas, given its perennial vegetation cover, tolerance to TE and obtained EO yields.