Browsing by Author "Tiwary, Abhishek"

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    Advance Oxidation Process (AOP) of Bisphenol A Using a Novel Surface-Functionalised Polyacrylonitrile (PAN) Fibre Catalyst
    (MDPI, 2022-02-18) Tiwary, Abhishek; Chi-Tangyie, George; Wang, Jiafan; Farias, Jorgelina; Huddersman, Katherine
    Bisphenol A (BPA) is a well-known endocrine disruptor in the environment which is not readily oxidised during wastewater treatment at Municipal Authorities. The aim of this work is to evaluate the environmental value of the wastewater treatment of a novel heterogeneous oxidation catalyst by means of the degradation of BPA, avoiding sewage sludge and its post-treatments. A surface-functionalised polyacrylonitrile (PAN) mesh has been produced by reaction of the cyano group of PAN with hydrazine and hydroxylamine salts. This surface-functionalised PAN is then exposed to iron (III) salt solution to promote the ligation of Fe(III) to the functional groups to form the active catalytic site. The experiments were set up in two different batch reactors at laboratory scale at different temperatures and initial pH. The degradation of BPA was detected by measuring the absorbance of BPA in Reverse Phase High Performance Liquid Chromatography at 280 nm. A total elimination of 75 ppm of BPA in less than 30 min was achieved under 300 ppm H2O2 , 0.5 g PAN catalyst, initial pH 3 and 60 ◦C. Almost no adsorption of BPA on the catalyst was detected and there was no significant difference in activity of the catalyst after use for two cycles.
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    Air Pollution Abatement from Green-Blue-Grey Infrastructure
    (Innovation Press, 2024-11-12) Kumar Prashant; Tiwary, Abhishek
    Green-blue-grey infrastructure (GBGI) offers environmental benefits in urban areas, yet its impact on air pollution is under-researched, and the literature fragmented. This review evaluates quantitative studies on GBGI's capability to mitigate air pollution, compares their specific pollutant removal processes, and identifies areas for further investigation. Of the 51 GBGI types reviewed, only 22 provided quantitative pollution reduction data. Street trees and mixed-GBGI are the most studied GBGIs, with efficacy influenced by wind, GBGI type vegetation characteristics, and urban morphology. Negative percentages denote worsening air quality, while positive reflect improvement. The 22 different GBGI grouped into eight main categories provide an average (±s.d.) reduction in air pollution of 16±21% , with substantial reduction shown by linear features (23±21%), parks (22±34%), constructed GI (14±25%), and other non-sealed urban areas (14±20%). Other individual GBGI reducing air pollutants include woodlands (21±38%), hedges (14±25%), green walls (14±27%), shrubland (12±20%), green roofs (13±23%), parks (9±36%), and mixed-GBGI (7±23%). On average, GBGI reduced PM1, PM2.5, PM10, UFP and BC by 13±21%, 1±25%, 7±42%, 27±27% and 16±41%, respectively. GBGI also lowered gaseous pollutants CO, O3 and NOx by 10±21%, 7±21% and 12±36%, on average, respectively. Linear (e.g., street trees and hedges) and constructed (e.g., green walls) features can impact local air quality positively or negatively, based on the configuration and density of the built environment. Street trees generally showed adverse effects in street canyons and beneficial outcomes in open-road conditions. Climate change could worsen air pollution problems and impact GBGI effectiveness by shifting climate zones. In Europe and China, climate shifts are anticipated to affect 8of the 22 GBGIs, with the rest expected to remain resilient. Despite GBGI's potential to enhance air quality, the meta-analysis highlights the need for standardised reporting structure to enable meaningful comparisons and effectively integrate findings into urban pollution and climate strategies.
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    An Innovative Method to Remove Phenols from Olive Mill Wastewater Using Heterogeneous Modified Polyacrylonitrile (PAN) Catalyst
    (IWA, 2024-08-23) Huddersman, Katherine; Milnes, Hannah; Tiwary, Abhishek; Matouq, Mohammed; Alayed, Omar; Kloub, Nasir
    Phenolic compounds contained in Olive Oil Mill Wastewater cause environmental issues when left untreated. A novel heterogeneous surface functionalised nanocoated polyacrylonitrile (PAN) mesh used as a Fentons’ catalyst acting with hydrogen peroxide gave 70-100% phenol reduction and an average TOC reduction of 64.7% when 7 phenols as described below were individually treated (100 mg/L phenolic, 500 mg/L H2O2, 12 g catalyst, 20 °C). As a mixture of 7 phenols (100 mg/L of each, 12 g catalyst, 3500mg/L H2O2); trans-cinnamic acid, p-coumaric acid, caffeic acid, vanillic acid, ferulic acid, tyrosol and hydroxytyrosol there was 77.5% phenol and 43.9% TOC reduction. The addition of UVc light (100 mg/L phenolic, 500 mg/L H2O2, 12 g catalyst, 20 °C, UV-flux 2.66 mW/cm2) significantly improved the degradation of the initial phenolic concentration by 98% in the individual treatments. A pH of 3 and a temperature of 30℃ were found to be the most effective and efficient. The fresh and regenerated catalysts were both recycled over 10 cycles before deactivation which shows promise for continuous flow and scale up for use as an olive oil mill wastewater treatment.
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    Assessment and mitigation of the environmental burdens to air from land applied food-based digestate
    (Elsevier, 2015-02-14) Tiwary, Abhishek; Williams, Ian; Pant, Dinesh; Kishore, V V N
    Anaerobic digestion (AD) of putrescible urban waste for energy recovery has seen rapid growth over recent years. In order to ascertain its systems scale sustainability, however, determination of the environmental fate of the large volume of digestate generated during the process is indispensable. This paper evaluates the environmental burdens to air associated with land applied food-based digestate in terms of primary pollutants (ammonia, nitrogen dioxide) and greenhouse gases (methane and nitrous oxide). The assessments have been made in two stages – first, the emissions from surface application of food-based digestate are quantified for the business as usual (BAU). In the next step, environmental burden minimisation potentials for the following three mitigation measures are estimated – mixed waste digestate (MWD), soil-incorporated digestate (SID), and post-methanated digestate (PMD). Overall, the mitigation scenarios demonstrated considerable NH3, CH4 and N2O burden minimisation potentials, with positive implications for both climate change and urban pollution.
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    Assessment of autonomous renewable energy system operability under extreme events and disasters
    (Elsevier, 2021-01-17) Espinoza, Oscar; Tiwary, Abhishek
    Autonomous, hybrid renewable energy systems (HRES) are increasingly being deployed in geographically challenging terrains, often lacking adequate resilience planning for natural disasters. An assessment framework is developed to evaluate sustainable HRES design for remote off-grid application, ensuring its operability under an extreme event, i.e. its ability to absorb the shock event and continue operating. Optimal HRES configurations are obtained for different extreme events, applying Pareto optimality with key criteria of minimising the number of black outs constrained by Net Present Cost (NPC). The framework is demonstrated for a remote location in Chile. Operability of an HRES under an extreme event is found to involve a trade-off between the investment decision to reduce the vulnerability of RET components and to enhance its energy storage. The optimised HRES is found to be cost-effective for resilience against seasonal events (for flooding and snowstorm the additional NPC is 4.6%, 7.4% respectively) but unsustainable for low probability-high impact events (for earthquakes the additional NPC of 20.5% largely from increase investment in storage capacity). The study also highlights the role of the dispatch strategy in enabling a micro hydro as a secondary storage component for both fulfilling the unmet loads and for charging batteries.
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    Co-managing carbon and air quality: pros and cons of local sustainability initiatives
    (Taylor & Francis, 2013-06-11) Tiwary, Abhishek; Chatterton, Tim; Namdeo, Anil
    This paper reports the pros and cons of co-management (i.e. concerted actions towards climate change and air quality management) through local sustainability initiatives using three case studies, each encompassing the planning and management issues at local government levels. Case study I is policy-based and reports the outcome of a consultation exercise while case studies II and III have greater scientific bearing. These case studies pave the way for development of a more integrated Climate Change Strategy Action Plan at local scales, specifically regarding policies on emissions sources from transportation and decentralised energy. They highlight the merits and the trade-offs of implementing local scale co-management practices, using a more integrated planning framework than what is currently under offer. We recognise that delivery of such ambitious, cross-cutting agenda may be impeded, primarily owing to limited expertise in assessing the synergies and the expected outcomes from cross-fertility between these two arenas. This calls for a step-change through more cohesive, cross-disciplinary policy frameworks, going beyond the local administrative spheres to maximise the co-management potentials while mitigating the wider environmental impacts.
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    A community-scale hybrid energy system integrating biomass for localised solid waste and renewable energy solution: Evaluations in UK and Bulgaria
    (Elsevier, 2019-02-27) Tiwary, Abhishek; Williams, Ian; Spasova, Stanislava
    Growing pace of urban living is expected to simultaneously aggravate both the waste and the energy crises. This study presents feasibility assessment of a community scale hybrid renewable energy system (HRES) utilising biomass to serve the local energy needs while reducing the household solid waste volume. A modelling framework is presented and evaluated for a biomass HRES, comprising of a Wind turbine-PV Array-Biogas generator-Battery system, applied to two European cities - Gateshead (UK) and Sofia (Bulgaria) - accounting for their distinct domestic biowaste profiles, renewable resources and energy practices. Biogas generator is found to make the most substantial share of electricity generation (up to 60–65% of total), hence offering a stable community-scale basal electricity generation potential, alongside reduction in disposal costs of local solid waste. Net present cost for the biomass-integrated HRESs is found within 5% of each other, despite significant differences in the availability of solar and wind resources at the two sites. Based on a survey questionnaire targeting construction companies and energy solution developers, project costs and planning regulatory red tapes were identified as the two common implementation challenges in both the countries, with lack of awareness of HRES as a further limitation in Bulgaria, impeding wider uptake of this initiative.
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    Development of multi-functional streetscape green infrastructure using a performance index approach
    (Elsevier, 2015-09-26) Tiwary, Abhishek; Williams, Ian; Heidrich, Oliver; Namdeo, Anil; Bandaru, Bandaru; Calfapietra, Carlo
    This paper presents a performance evaluation framework for streetscape vegetation. A performance index (PI) is conceived using the following seven traits, specific to the street environments – Pollution Flux Potential (PFP), Carbon Sequestration Potential (CSP), Thermal Comfort Potential (TCP), Noise Attenuation Potential (NAP), Biomass Energy Potential (BEP), Environmental Stress Tolerance (EST) and Crown Projection Factor (CPF). Its application is demonstrated through a case study using fifteen street vegetation species from the UK, utilising a combination of direct field measurements and inventoried literature data. Our results indicate greater preference to small-to-medium size trees and evergreen shrubs over larger trees for streetscaping. The proposed PI approach can be potentially applied two-fold: one, for evaluation of the performance of the existing street vegetation, facilitating the prospects for further improving them through management strategies and better species selection; two, for planning new streetscapes and multi-functional biomass as part of extending the green urban infrastructure.
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    Effluent parameters prediction of a biological nutrient removal (BNR) process using different machine learning methods: A case study
    (Elsevier, 2023-12-30) Manav-Demir, N.; Huseyin Baran, G.; Ersoy, O.; Kurugollu, F.; Bajpai, Vivek K.; Tiwary, Abhishek; Debik, E.
    This paper proposes a novel targeted blend of machine learning (ML) based approaches for controlling wastewater treatment plant (WWTP) operation by predicting distributions of key effluent parameters of a biological nutrient removal (BNR) process. Two years of data were collected from Plajyolu wastewater treatment plant in Kocaeli, Türkiye and the effluent parameters were predicted using six machine learning algorithms to compare their performances. Based on mean absolute percentage error (MAPE) metric only, support vector regression machine (SVRM) with linear kernel method showed a good agreement for COD and BOD5, with the MAPE values of about 9% and 0.9%, respectively. Random Forest (RF) and EXtreme Gradient Boosting (XGBoost) regression were found to be the best algorithms for TN and TP effluent parameters, with the MAPE values of about 34% and 27%, respectively. Further, when the results were evaluated together according to all the performance metrics, RF, SVRM (with both linear kernel and RBF kernel), and Hybrid Regression algorithms generally made more successful predictions than Light GBM and XGBoost algorithms for all the parameters. Through this case study we demonstrated selective application of ML algorithms can be used to predict different effluent parameters more effectively. Wider implementation of this approach can potentially reduce the resource demands for active monitoring the environmental performance of WWTPs.
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    Emerging Perspectives on Diverse Nature-Oriented Sustainability Strategies
    (MDPI, 2024-01-19) Tiwary, Abhishek; Brown, Neil
    Increasing levels of nature-oriented sustainability strategies (NOSSs) are being recognized as offering solutions to combat climate change at scale, both through transformative infrastructure and autonomous technology innovations. This paper presents a synopsis of the mainstream literature covering the emerging trends from the last two decades across two broad trajectories of NOSS initiatives—“nature-inspired” (NI)- and “nature-based solution” (NBS)-oriented approaches. The specific scopes of these two approaches have been categorized into disciplinary fields, highlighting their peculiarities and commonalities, followed by an appreciation of their evolutionary trends based on the literature abundance over three distinct time-horizons—pre 2000, 2000–2010, and 2011–2021. We find ambitious levels of sustainability-led developments are driving NOSS initiatives beyond 2010; in particular, the increased level of NI approaches in the field of chemical processing, material structure, and renewable energy. Likewise, there has been rapid growth in NBS approaches in the last decade from a systems perspective, reducing the level of grey infrastructure by offering sustainable alternatives to the ecologically destructive technologies. However, we identify some crucial red herrings to the main-streaming of NOSSs as a ‘true sustainability solution’, such as the inherent challenges in their scaling-up, operation and management, and in ensuring ecologically and culturally adaptive interventions across different global contexts.
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    Emerging pollutants removal in full-scale biological treatment plants: A case study
    (Elsevier, 2022-11-26) Tiwary, Abhishek; Ulucan-Altuntas, Kubra; Manav-Demir, N; Huddersman, Katherine; Debik, Eyup
    Wastewater treatment plants (WWTPs) are the main source of emerging pollutants encountered in surface water, albeit existing standards apply to a very limited number of emerging compounds. This paper presents a case study on non-target analysis, performed on influent and effluent samples from the WWTPs in Kocaeli, Türkiye. The samples were concentrated through solid-phase extraction, followed by LC-MS/MS analysis to identify emerging compounds, typically found in wastewater and treated wastewater. The data obtained was evaluated based on wastewater characteristics and the flow rate of the selected WWTPs. The removal of detected emerging compounds was calculated and classified as — “not removed”, and “partially removed”. Our analysis showed pharmaceutics as the most prevalent detected compounds, with the highest level of removal efficiency. The study demonstrated the necessity for redesigning conventional WWTPs to reduce the potential escape of emerging pollutants, with potential accumulation and transformation into harmful by-products in the environment.
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    Management of nature-based goods and services provisioning from the urban common: a pan-European perspective
    (Springer, 2020-02-20) Tiwary, Abhishek; Vilhar, Ursa; Zhiyanski, Miglena; Stojanovski, Vladimir; Dinca, Lucian
    The role of the urban common (i.e. shared space and resources) in sustainable provisioning of goods and services to city dwellers is discussed in this paper. Focusing on tree-based green infrastructure, the study scope includes three categories of provisioning (woody biomass, food/fibre, and non-timber forest products, i.e. NTFPs), alongside three categories of supporting services (fresh water replenishment, soil nutrient restoration, building preservation). As a first step, prospects of utilizing the urban common as facilitator of nature-based solution to the earmarked provisioning services are evaluated through dedicated literature survey and expert elicitation on perceived impact of environmental change triggers and management interventions (planning and/or governance). This is followed by a structured review of the state of affairs in four European cities (London, Amsterdam, Sofia, Ljubljana), representing different macro-geographical regions with distinct socio-economic drivers in managing these provisioning services. The pan-European expert elicitation exercise noted active management of the urban common as positively impacting on the performance of the majority of provisioning services, while environmental change impacts were found to be overriding and adversely influencing the provisioning of material resources (mainly NTFPs and woody biomass). The four-city case study highlighted some regional peculiarities in connecting the city dwellers to the urban common and identified the need to overcome socio-cultural barriers for enhancing pan-European best practice sharing in the management of goods and services provisioning. This is deemed essential to pave way for an emerging perspective on sustainable utilization of the urban common as an enabler for nature-based solution, making it fit for purpose in meeting the astronomical demands of future urban living.
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    Measurement and analysis of household carbon: The case of a UK city
    (Elsevier, 2016-01-07) Allinson, David; Irvine, Katherine; Edmondson, Jill; Tiwary, Abhishek; Hill, Graeme; Morris, Jonathan; Bell, Margaret; Davies, Zoe; Firth, Steven; Fisher, Jill; Gaston, Kevin; Leake, Jonathan; McHugh, Nicola; Namdeo, Anil; Rylatt, Mark; Lomas, Kevin
    There is currently a lack of data recording the carbon and emissions inventory at household level. This paper presents a multi-disciplinary, bottom-up approach for estimation and analysis of the carbon emissions, and the organic carbon (OC) stored in gardens, using a sample of 575 households across a UK city. The annual emission of carbon dioxide emissions from energy used in the homes was measured, personal transport emissions were assessed through a household survey and OC stores estimated from soil sampling and vegetation surveys. The results showed that overall carbon patterns were skewed with highest emitting third of the households being responsible for more than 50% of the emissions and around 50% of garden OC storage. There was diversity in the relative contribution that gas, electricity and personal transport made to each household’s total and different patterns were observed for high, medium and low emitting households. Targeting households with high carbon emissions from one source would not reliably identify them as high emitters overall. While carbon emissions could not be offset by growing trees in gardens, there were considerable amounts of stored OC in gardens which ought to be protected. Exploratory analysis of the multiple drivers of emissions was conducted using a combination of primary and secondary data. These findings will be relevant in devising effective policy instruments for combatting city scale green-house gas emissions from domestic end-use energy demand.
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    Monitoring Hazards in Dam Environments Using Remote Sensing Techniques: Case of Kulekhani-I Reservoir in Nepal
    (MDPI, 2024-11-12) Rimal, Bhagawat; Tiwary, Abhishek
    Maintaining the operability of a hydroelectric power station at a scale originally designed is being compromised by continuous reservoir sedimentation. The underlying factors include a complex mix of landscape alterations owing to natural and anthropogenic activities around dam areas, such as gully erosion, landslides, floods triggered by heavy rainfall, climate change, and construction activities. The hydropower projects in the low-to-mid mountain regions of Nepal are witnessing a combination of these phenomena, affecting their optimal performance in meeting long-term sustainable power supply targets. This paper presents a combination of geo-spatial analysis and field evaluations to identify the trends from Kulekhani-I, one of the oldest storage-type hydropower projects in Nepal, using long-term time series remote sensing satellite imagery from 1988 to 2020. Our analysis shows an expansion of the surface water content area over time, attributed mainly to high sedimentation deposition owing to multiple factors. This study has identified an urgent need for addressing the following two key contributory factors through an effective control mechanism to avoid rapid sedimentation in the reservoirs: natural—landslides and floods leading to mainly silt deposition during heavy rainfalls; and anthropogenic—road construction materials dumped directly in the reservoir. Effective implementation of a remote sensing monitoring scheme can safeguard future damages to dam environments of more recently built storage-type hydropower projects.
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    Net zero: My drive for innovation, enterprise and lifelong learning
    (Taylor & Francis, 2024-04-19) Tiwary, Abhishek
    Net zero sounds altruistic in terms of its ethos but highly demanding and intertwined (signifying its complexity) when it comes to its delivery. As well, let’s not forget, its existential relation with Anthropocene (albeit in other names, such as carbon neutral, zero emissions, etc.) has come about due to our own misgivings and will probably continue in some form until the last one of us will survive on the Earth. In this chapter, I will first dwell upon the role of evolutionary science/engineering in shaping my personal academic and research journey into net zero. I strongly consider my research over the past two decades has been enriched from the interdisciplinary remits of net zero challenges. More recent activities have focused on integrating sustainability into engineering projects, primarily tackling the dilemma for achieving sustainable net zero at the energy-environment nexus. There is certainly lot more to be done.
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    Reducing non-residential asset sanitisation water footprint for improved public health in water-deficient cities
    (Elsevier, 2021-08-15) Tiwary, Abhishek; Bhattacharyya, Subhes; Matouq, Mohammed
    This paper evaluates the potential for reconfiguring city-scale clean water demand by reducing the non-residential asset sanitsation water footprint. A novel methodological framework is proposed for assessing the feasibility of a mix of three surface sanitisation measures (Manual surface wiping, Mechanical cleaning/Rapid disinfectant spraying, Ultraviolet germicidal irradiation-UVGI treatment) in terms of a Sanitisation waterfootprint index (SWI); three typical application scenarios are considered – high risk-high frequency, moderate risk-moderate frequency, moderate risk-low frequency. The UVGI treatment outperforms the other two surface treatment methods, particularly in high risk-high frequency scenario in the healthcare setting, with SWI as low as 2%. Further, case-study evidence from a ward-level spatial analysis using real-world data estimates SWI ranging between 0-30% in those wards with greater commercial/public assets, showing clear merit of this framework in re-configuring city-scale public health sanitisation water footprint. A cost-benefit analysis (involving resources – staffing, water and chemicals; capital expenditure, and energy costs) shows superior performance of UVGI treatment over the other two methods from the second year onwards, surpassing the initial cost-effectiveness for corresponding manual or mechanical cleaning. Wider implementation of this framework can foster strategic transformation of city-scale water footprint, which is deemed essential for ensuring sustainable growth of water deficient cities globally.
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    Spatial planning of public charging points using multi-dimensional analysis of early adopters of electric vehicles for a city region
    (Elsevier, 2013-10-08) Namdeo, Anil; Tiwary, Abhishek; Dziurla, Robert
    The success of a mass roll out of Plug-in electric vehicles (PEVs) is largely underpinned by establishment of suitable charging infrastructure. This paper presents a geospatial modelling approach, exploring the potentials for deployment of publicly accessible charging opportunities for consumers based on two traits — one, trip characteristics (journey purpose and destinations); two, PEV adoption intensity. Its applicability is demonstrated through a case study, which combines census statistics indicating lifestyle trends, family size, age group and affordability with travel patterns for an administrative region in the North-East England. Three categories of potential PEV users have been identified — ‘New Urban Colonists’, ‘City Adventurers’ and ‘Corporate Chieftains’. Analysis results indicate that Corporate Chieftains, primarily residing in peri-urban locations, with multi-car ownership and availability of onsite overnight charging facilities form the strongest group of early adopters, irrespective of public charging provision. On the other hand, New Urban Colonists and City Adventurers, primarily residing in the inner-city regions, show potentials of forming a relatively bigger cohort of early PEV adopters but their uptake is found to be dependent largely on public charging facilities. Our study suggests that effective PEV diffusion in city-regions globally would require catering mainly to the demands of the latter group, focussing on development of a purpose-built public charging infrastructure, both for provision of on-street overnight charging facilities in residential locations and for fast charging at parking hubs (park and ride, amenities and commercial centres).
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    Techno-Economic Feasibility of a Grid-Connected Hybrid Renewable Energy System for a School in North-West Indonesia
    (Hapres, 2020-03-18) Tiwary, Abhishek; Illiandi, Biadelma
    Background: Schools typically have high diurnal fluctuation in electricity demand, with peak loads during daylight hours, which could be adequately met through harnessing solar renewable resources. This study demonstrates the strength of techno-economic assessment in selection and optimization of a grid-connected hybrid renewable energy system (HRES), utilizing local renewable resources to fulfil the daytime electricity demand for a school in northwest Indonesia. Methods: Three different scenarios are developed for optimizing the HRES configurations, comprising of PV panels, Wind turbine, Battery and Inverter. The following optimization parameters are used—one, technological performance of the HRES, in terms of their energy output to fulfil the energy deficit; two, economic performance of the HRES, in terms of their net present cost (NPC) and payback periods. Results: A clear trade-off is noted between the level of complexity of the three HRES, their renewable electricity generation potentials, NPC and payback periods. Scenario II, comprising of Solar PV and Inverter only, is found to be the most feasible and cost-effective HRES, with the optimized configuration of 245 kW PV capacity and 184 kW inverter having the lowest initial capital cost of US$ 51,686 and a payback time of 4 years to meet the school’s annual electricity load of 114,654 kWh. Its NPC is US$ −138,017 at the 20th year of installation. The negative value in year 20 is achieved through the sale of 40% of the renewable energy back to the grid. Conclusions: Techno-economic assessment can provide useful decision support in designing HRES relying on solar energy to serve predominantly daytime school electricity requirements in tropical countries.
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    Trade-offs between economic and environmental performance of an autonomous hybrid energy system using micro hydro
    (Elsevier, 2018-06-15) Tiwary, Abhishek; Apichonnabutr, Wuttipong
    This paper evaluates the trade-offs between economic and environmental performance of an autonomous energy system utilising an existing Micro hydro power plant while improving its future reliability. The analysis primarily focuses on developing sustainable alternative to excessive reliance on Diesel Gensets in fulfilling the increasing seasonal shortfall in electricity supply from standalone Micro hydros. First, a preliminary assessment is conducted using hypothetical future shortfall in electricity supply from a Micro hydro of 10%, 20% and 30%, compared to a baseline of 2% shortfall, which shows drastic increase in the environmental costs (combined human health and ecological) by as much as 400%, 900%, 1400% respectively from continued use of conventional Diesel Genset. In the next step, a ‘Micro hydro sustainability indicator’ is formulated as the ratio of environmental costs to net present costs of different hybrid options. This is estimated through a mixed assessment framework, which combines consumer engagement for understanding the current and the projected future diurnal and the seasonal electrical loads along with quantitative evaluation of the corresponding costs. Finally, a demonstration case study implements this framework at the Khun Pang micro hydropower project in Si Lanna National Park within Chiang Mai province, northern Thailand for two scenarios – Scenario 1 (circa 2016–17, annual shortfall of 4% i.e. 571 kW h); Scenario 2 (circa 2025, projected future annual shortfall of 12.5% i.e. 3904 kW h). For smaller unmet load of up to 4% in Scenario 1, Diesel Genset turns out to be the most preferred hybrid option, irrespective of whether the environmental costs were included alongside the net present costs or not. However, for an increased future load of 12.5% in Scenario 2, including the environmental costs makes the hybrid Micro hydro-PV-Diesel-Battery system cost-competitive to the Diesel only option. Considering a 25-year project lifespan, it becomes the most sustainable solution for retrofitting micro hydro facilities in ecologically sensitive locations in order to meet future shortfall in electricity supply, with improved renewable penetration of up to 97.5%.