Energy availability and reliability are essential for economic growth and sustainable development. The problems with growing energy demand could be addressed by supply-side energy management. However, this task has become increasingly challenging due to high fluctuations in electricity demand and the increasing penetration of intermittent renewable energy into the electricity supply mix. This study aims to investigate the energy demand flexibility potential in the energy-intensive cement production sector. A mixed integer linear programming model (MILP) has been developed to flatten the grid's hourly demand curve by minimizing the industrial customer's hourly peak loads and maximizing the shifting of demand to off-peak periods. The result reveals that the demand flexibility potential of the case study cement plants is about 495 MWh per day, constituting approximately 28 % of the daily total electrical energy used by these cement plants, proving that the cement industry is a potential candidate for demand response strategies. By adapting the proposed model, the loads of the case study plants during the peak period of the day are reduced by an average of 75 %. In addition, case study plants have achieved an overall reduction of 188 t of CO2 emissions per day. Furthermore, the cost of consumed electrical energy for a day decreased on average by 14 % in these plants. Thus, the proposed model can help minimize the impact on grid instability and the cost of energy consumption of an industrial customer. Scenarios such as the variation of the capacity factor and onsite electrical power generation, i.e., waste heat recovery power plants, can promote the demand response strategies in the cement sub-sector. The study could be useful to energy-intensive industries and relevant policymakers to understand the demand response in maintaining power system reliability and explore ways to implement demand-side energy management strategies with appropriate electricity tariffs.

Achieving sustainable biowaste management is a key challenge for cities worldwide. In this context, biowaste valorization is an indispensable option for managing unavoidable biowaste and reducing the associated methane emissions. Several innovations that enable biowaste valorization are technologically mature. However, their implementation is still limited in most cities around the world. Therefore, it is essential to better understand the different pathways towards implementing biowaste valorization. This paper presents a case-study of two countries at different phases in their transition to biowaste valorization: Sweden as a case at a mature phase and Greece as a case at a formative phase. We apply the Technological Innovation Systems framework to investigate how innovation systems for biowaste valorization develop and associated path-dependencies. Our findings show that various path-dependence lock-ins can occur at different transition phases. Our empirical insights suggest that a focus on the diffusion of certain mature innovations can support the growth of biowaste valorization systems. However, it can also lead to path-dependence lock-ins that influence the systems’ resilience to shocks. We thus recommend decision-makers to pursue balance between the rapid diffusion of mature innovations for biowaste valorization and parallel support for experimenting with more radical innovations to harness the systems’ resilience to shocks.

Even if aviation only accounts for 2 % of global energy-related CO2 emissions, but it is the most challenging sector to decarbonize. As aviation demand grows and the need for sustainable jet fuels becomes urgent, green hydrogen could substitute conventional fossil fuels, thereby enabling carbon-free flights. This study investigates a techno-economic analysis of on-site versus off-site green hydrogen supply chains. A case study at the ToulouseBlagnac airport (Europe's first station for the production and distribution of renewable hydrogen) in France is developed to meet commercial aviation's hydrogen fuel demand between 2025 and 2050. Demand of hydrogen is projected based on the trend of jet fuel consumption. First, the cost of solar-based renewable electricity is estimated at the two green hydrogen production sites using levelized cost of electricity production. Second, levelized cost of hydrogen (LCOH) is evaluated for three value chain scenarios: one on-site (Toulouse airport) and two off-site (Marseille) for gaseous and cryogenic transportation of liquid hydrogen (LH2). A relative cost advantage is shown for the off-site case with cryogenic truck transportation at LCOH of <euro>9.43/kg.LH2. This study also reveals the importance of electricity price, investment costs, operation costs, economies of scale, and transportation distance in different scenarios.

Cement production is a major consumer of energy and the largest source of industrial CO2 emissions. This study aims to perform an environmental life cycle assessment of clinker and cement production in Ethiopia, using ReCiPe impact assessment method. Inventory data (material, energy, and transportation) is collected from seven major Ethiopian cement industries. The midpoint analysis identified nine hotspot environmental concerns: global warming, ozone formation (human health and terrestrial ecosystem), particulate matter formation, terrestrial (acidification and ecotoxicity), freshwater eutrophication, human carcinogenic toxicity, and fossil resource scarcity. Human health emerged as the most significantly affected endpoint damage category by the midpoint impacts. Among the process stages included in clinker system boundary, clinker production phase (kiln emissions) is a significant contributor to the total score of the hotspot impacts, ranging from 60.7% to 91.8%. The clinker system is responsible for over 81.03% of the overall environmental burden of cement. The sensitivity analysis reveals that a 5% change in kiln energy consumption and transportation burden could lead to a reduction in hotspot impacts ranging from 1.8% to 5%. To foster reliability of this study, uncertainty analysis is also conducted. Overall, the findings indicate the need to enhance environmental sustainability in Ethiopian cement production.

In life-cycle costing of thermal energy systems, the basis of costing could be mass or exergy and the approach followed could be deterministic or stochastics. In thermal energy systems with end products/services such as hot air, hot water, steam etc. the value addition is due to higher exergy content; therefore, exergy is a logical basis of costing and stochastics is a practical approach capturing uncertainties of input variables. This paper proposes a novel framework named as stochastic Monte Carlo-based exergy costing (SMXC) for assessment of solar hot water systems. The annual hours of operation, maintenance cost, service life, and capital cost have been identified as highly sensitive input variables. The costs based on mass and exergy content of hot water in deterministic life-cycle costing method are estimated at 0.296 and 0.304 US cent/kg, respectively. The mean values of mass and exergy costs of hot water using Monte Carlo-based stochastics life-cycle costing method are 0.302 and 0.310 US cent/kg. A very low value (i.e. 2.4%) of the exergo-economic factor (f) for the solar water heater indicates the poor exergetic efficiency; therefore, capital investment to improve its efficiency is justified. The methodological approach can be extended to examine the probabilistic exergo-economic cost of array of thermal energy products when the parametric uncertainties play a key role.

The upscaling of novel carbon dioxide removal, such as bioenergy carbon capture and storage (BECCS), to gigatonne scales is an urgent priority if global warming is to be limited to well below 2 °C. But political, economic, social, technological, environmental and regulatory uncertainty permeates BECCS projects and deters investors. To address this, we explore options to improve the robustness of BECCS deployment strategies in the face of multi-dimensional uncertainties. We apply Dynamic Adaptive Planning (DAP) through expert interviews and Robust Decision Making (RDM) through exploratory modelling, two decision making under deep uncertainty methods, to the case of Stockholm Exergi, an early mover aiming to deploy BECCS at a combined heat and power plant in the capital of Sweden. The main contributions of the research are to 1) illustrate how a quantification of robustness against uncertainty can support an investment decision to deploy BECCS 2) comprehensively cover uncertain vulnerabilities and opportunities of deploying BECCS, and 3) identify critical scenarios and adaptations to manage these uncertainties. The main conclusions are: investing in BECCS is relatively robust if assessing performance across many scenarios and if comparing the worst-cases of either investing, or not doing so. Not investing could miss out on up to € 3.8 billion in terms of net present value. The critical uncertainties of BECCS can be managed by strengthening biomass sustainability strategies and by gaining support for negative emission trading regulation on carbon markets, e.g., voluntary or Paris Agreement Article 6. Even in vulnerable scenarios of average electricity prices above 82 €/MWh, if trading regulation is implemented before 2030 and if negative emission prices exceed 151 €/CO2, investing in BECCS performs better than not doing so in 96% of cases. We suggest that facility-level parameters and cost-reductions are of little importance for BECCS investments and upscaling. It is regulatory certainty of operating revenues, e.g., through negative emission markets, that needs to be provided by policymakers.

Background: Cooking with traditional fuels can lead to severe health issues caused by household air pollution, and can also affect gender equality and drive environmental degradation. In Nepal, despite government efforts to promote electric cooking, more than half of the population still uses traditional fuels, with electric cooking adoption remaining below 1%. Several of the barriers to and enablers of clean cooking vary geographically; however, few studies have considered spatial explicit information in planning national-scale transitions to clean cooking. In this study we provide a spatially explicit roadmap to estimate the required investments and benefits gained from the transition across Nepal. Methods: This study uses geospatial modelling methods to evaluate strategies to achieve the Government of Nepal's vision for a national-scale transition to clean cooking. We integrate the open-source clean cooking geospatial assessment tool OnStove and a spatial multicriteria analysis model. With OnStove, we evaluate which cooking technologies and fuels maximise the net benefits of a clean-cooking transition across each km2 of the region. With the multicriteria analysis, we weigh stakeholder preferences and prioritise areas of action where policy should be implemented. We used the most up-to-date geospatial data to the year 2023, such as the High Resolution Settlement Layer, Open Street Maps’ road networks, the Global Human Settlement Layer, NASA/USGS forest cover maps, and Facebook's Relative Wealth Index, among others. We also relied on data from the Nepal Oil Corporation, the Nepal Electricity Agency, the Central Bureau of Statistic's 2021 national census, and the Alternative Energy Promotion Center. We evaluate four scenarios capturing advances on clean cooking policy up to the year 2022, current market inefficiencies, and the potential effects of new policies for clean-cooking transition in Nepal. Findings: Our results show that transitional and clean cooking technologies provide higher net benefits than traditional options everywhere across Nepal in all scenarios. Our net-benefit analysis shows that around 9563 deaths could be averted yearly if benefits and externalities were perceived and valued correctly. Furthermore, substantial benefits could be achieved in regard to greenhouse gas emissions avoidance, time saved, and health-cost reductions. Our results also show that the current subsidy strategy from the Government of Nepal is well aligned with the benefits achieved under a cost–benefit analysis. In this context, electric cooking can bring the highest benefits to the largest part of the population. The analysis showed how high subsidies for liquefied petroleum gas in Nepal can present trade-offs with energy security and independence, and how this could be avoided by transferring part of the subsidy to cover differentiated electric cooking tariffs. Accounting for stakeholder preferences and sociodemographic and geographical differences to prioritise areas of focus can balance affordability constraints and target the most vulnerable people first, thus achieving integrated and inclusive planning. Interpretation: Using spatially explicit modelling approaches to evaluate strategies for a clean cooking transition can provide more nuanced results that have not been possible before. This approach can enable data-driven and integrated planning to help to understand which locations of a study area should be prioritised for policy application. Integrated planning can help to reduce affordability constraints on the population and design strategies for a sustainable and inclusive transition. These strategies allow financial institutions, donors, impact investors, development organisations, and government agencies to use their resources, funds, and assistance to create a large impact. Funding: Clean Cooking Alliance.

In the face of climate change, urban governance systems must adapt to uncertainties and emerging pressures. Polycentric governance, characterized by multiple decision-making centers at different scales, enables coordination across levels and provides flexibility, which allows for experimentation and context-specific action, catalyzing institutional innovations in cities. These innovations involve creating new structures and modifying existing ones to help cities better withstand and adapt to the impacts of climate change. There are plenty of studies on this issue in developed country context, but such studies in the context of developing countries are lacking, especially in India. This article aims to explore the influence of polycentric governance on institutional innovations, thereby offering insights on how it contributes to transformative urban governance in India, characterized by (1) stewarding capacity, (2) unlocking capacity, (3) transformative capacity, and (4) orchestrating capacity. The research findings suggest that polycentric governance increases diversity and autonomy in decision-making centers across levels, which can enable more innovation or flexibility, leading to improving governance capacity to respond to changing circumstances, but these developments are still in nascent stage and further research is needed to assess the long-term sustainability of these capacities. The findings not only contribute to governance research and provide insights for policymaking, but also contribute to the broader discourse on urban resilience and sustainable development aligning with SDG 11 (sustainable cities and communities) and SDG 17 (partnerships for the goals) globally, especially in the Global South.

Household biogas plants (HBPs) are widely promoted in developing countries like Nepal to decarbonize the cooking fuel sector, mitigating greenhouse gas (GHG) emissions associated with traditional, non-clean cooking fuels. However, their decarbonization potential mainly relies on the overall GHG emissions associated with HBP and the avoidable emissions to be substituted by the HBP, and there is a lack of systematic studies evaluating these emissions under Nepalese context. This study addresses this gap, probably for the first time in Nepal, by analyzing GHG emissions associated with HBP, assessing their decarbonization potential under various operational conditions, and identifying opportunities to enhance the potential. Using a life cycle assessment (LCA) approach, we examined the decarbonization potential of HBPs and evaluated the impact of their operational uncertainties through sensitivity analysis. Our results indicate that HBPs could decarbonize the cooking fuel sector in Nepal by around 150,000 kt of CO2 equivalent annually; however, GHG emissions from about two-third of HBPs exceeded avoidable emissions, hindering their overall decarbonization potential. To improve this potential, we recommend strategies such as effective operation and maintenance, efficient digestate utilization, and context (regional, socioeconomic etc.) specific intervention policies such as biogas yield enhancement through codigestion of locally available feedstock. These findings provide valuable insights for policymakers aiming to assess and enhance the decarbonization potential of HBPs in Nepal and other parts of the developing countries under similar contexts.

Biomass has enormous potential globally, but it requires sustainable management and conversion into modern bioenergy that aligns with the Sustainable Development Goals (SDGs). This study assesses sustainable biomass potential for energy generation in South America, considering forestry, agriculture, agro-industrial, and municipal solid waste biomass. The Autoregressive Integrated Moving Average (ARIMA) time series forecasting model with data from the Food and Agriculture Organization Corporate Statistical Database (FAOSTAT) and the World Bank up to 2050 is used. In 2021, the total biomass theoretical potential amounts to 1214 million tonnes (Mt), projected to increase to 1371 Mt by 2050. The available technical potential for energy purposes ranges from 796 Mt in 2021 to 916 Mt by 2050, with approximately 66 % attributed to agricultural biomass, 10 % to agro-industrial biomass, 17 % to forestry biomass, and 7 % to municipal waste biomass. Notably, not all countries experience growth in bioenergy potential from 2021 to 2050. Increasing forestry biomass recoverability from 25 % to 75 % enhances the total technical potential by 7 % for 2050. Primary bioenergy potential, utilizing available biomass, ranges from 13,831–15,892 PJ between 2021 and 2050, equivalent to 1278 to 1444 Terawatt hour (TWhe) when considering biomass conversion to electric energy. The share of bioelectricity could be 24 % of the total electricity generation in 2021. Additionally, modern bioenergy could help achieve sustainable development goals and decarbonize the energy sector in the region. This assessment of modern bioenergy potential in South America is relevant for subsequent techno-economic and environmental evaluations towards global energy decarbonization by 2050.