Demand Reduction Research Articles

A Decision-Making Tool for Sustainable Energy Planning and Retrofitting in Danish Communities and Districts

This study presents a novel framework for city-level energy planning and retrofitting, tailored to Danish cities and neighborhoods. The framework addresses the challenges of large-scale urban energy modeling by integrating automated processes for data collection, energy demand prediction, and renewable energy integration. It combines open-source simulation tools and validated datasets, enabling efficient and scalable predictions of energy performance across urban areas, including streets, districts, and entire cities, with minimal user input. The key components include data collection and demand modeling, energy resource estimation, performance gap evaluation, and the design of retrofitting strategies with renewable energy integration. The DanCTPlan energy planning tool, developed based on this framework, was applied to two case studies in Denmark: a single street with 101 buildings and a district comprising five streets with 1284 buildings. In the single-street case, retrofitting all buildings to meet current regulations resulted in a 60.8% reduction in heat demand and a 5.8% reduction in electricity demand, with significant decreases in peak energy demands. The district-level retrofitting measures led to a 29.5% reduction in heat demand and a 2.4% reduction in electricity demand. Renewable energy scenarios demonstrated that photovoltaic systems supplying 30% of electricity demand and solar thermal systems meeting 10% of heating demand would require capacities of 2218 kW and 3540 kW, respectively. The framework’s predictive capabilities and flexibility position it as a robust tool to support decision-makers in developing sustainable and cost-effective energy strategies, paving the way toward establishing energy-efficient and positive energy districts.

Non-renewable energy demand reduction and positive energy buildings in Southern Europe’s urban forms

Non-renewable energy demand reduction and positive energy buildings in Southern Europe’s urban forms

European tourism demand in the face of climate change: asymmetric impacts, demand reallocation, and deseasonalisation strategies

Abstract The European tourism industry, a significant contributor to employment and income, is under threat due to climate change. This study, using data from 1315 European regions and considering a tourism-specific climate index and tourism typologies, examines the potential impact of climate change on tourism demand across the continent under four warming scenarios. We find that climate change impacts in Europe will be highly asymmetrical across regions and seasons, resulting in significant reallocations of tourism demand in space and time across all warming scenarios. A clear north-south pattern in tourism demand changes emerges, with northern regions benefiting and southern regions experiencing significant reductions, particularly under higher warming. Summer demand and coastal areas, where tourism demand is more concentrated, will be particularly affected. We also quantify the deseasonalising efforts necessary to maintain the status quo in the annual demand for tourism, involving relative reductions in summer demand and increases in shoulder and winter seasons.

Electricity Consumption and Efficiency Measures in Public Buildings: A Comprehensive Review

Industrialization and the expansion of service sectors have led to a significant increase in electricity consumption. This rising demand has also been observed in public buildings, which account for a considerable share of total electrical energy use. Coupled with the upward trend in energy prices, this increase has likewise escalated electricity costs in these sectors. The objective of this review is to compile studies that analyze electricity consumption in large public buildings, with a primary focus on universities, as well as works that propose or implement energy-saving measures aimed at reducing consumption. Throughout this review, it is observed that effective monitoring of consumption as well as the use of demand management systems can reduce electricity consumption by up to 15%. Additionally, the studies collected consistently highlight the need for improvements in real-time data monitoring to enhance energy management. Buildings that implement energy-saving measures achieve reductions in demand exceeding 10%, while those incorporating renewable energy systems are capable of covering between 40% and 50% of their energy needs. Of these systems, solar photovoltaic technology is that most widely adopted by public buildings, primarily due to its adaptability to the architectural characteristics and operational requirements of such facilities. This review underscores the substantial impact that optimized monitoring and renewable energy integration can have on reducing the energy footprint of large public facilities.

A sustainable and resilient humanitarian relief chain network design for distributing assembled relief items dynamically considering perishability, under disruption

Purpose Due to mitigate against natural disasters like earthquake and to distribute relief items, designing humanitarian relief chain networks is an attentional issue. Agile and efficient distribution of relief items after occurring a disaster is significant, especially when some of the relief items are perishable. Therefore, the purpose of this paper is to create a resilient and integrated decision-making structure to distribute relief items at demand points, considering two dimensions of sustainability, under disruption. Design/methodology/approach This study developed a mixed-integer nonlinear mathematical model to handle the pre- and post-disaster planning when a disaster occurs. The represented model has two objective functions: minimizing weighted unmet demand and total costs. Therefore, to convert this multi-objective problem into a single objective one, the e-constraint method was applied. Findings The main results showed that considering some resilience strategies has a significant effect in reducing the weighted amount of unmet demand and saves the total costs. More precisely, considering resilience strategies results in a 60% reduction in total unmet demand and 11% reduction in total pre-positioning costs. On the other hand, reducing the maximum response time with applying resilience strategies is another achievement of the present study. For these reasons, the use of these strategies can reduce people’s pain and suffer from natural disasters. In general, the application and effectiveness of sustainability dimensions and resilience strategies in the introduced humanitarian relief chain network were analyzed. Practical implications To verify the applicability of this study, this model is applied on a probable real-life case study in Tehran. Finally, some managerial insights are discussed to help humanitarian organizations, managers and stakeholders to make better decisions to reduce negative effects of natural disasters. Originality/value This paper introduced a two-stage stochastic mathematical model for designing a resilient humanitarian relief chain network under disruption, at pre- and post-disaster stages. Also, economic and social dimensions of sustainability are considered in this study. Moreover, assembling perishable and im-perishable relief items as relief kits, dynamically is a main contribution of this research.

Unilateral Market Power in Financial Transmission Rights Auctions

This paper explores market participants’ incentives to exercise unilateral market power in financial transmission rights (FTR) auctions. I present a model of strategic bidding in FTR auctions that illustrates how the standard market clearing mechanism for FTR auctions facilitates cross-path competition, limiting the profitability of demand reduction. Simulation evidence suggests that this force can dramatically reduce rents from unilateral market power relative to other sources of auction revenue shortfalls, highlighting potential adverse effects from proposed market reforms such as decentralized FTR sales and bidding-path restrictions that may weaken cross-path competition. JEL Classification: D44, D47, Q49

The role of membrane technology in palm oil mill effluent (POME) decontamination: Current trends and future prospects.

This article reviews the role of membrane systems in treating palm oil mill effluent (POME), a waste generated by the palm industry. The review focuses on various membrane systems such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO), highlighting their effectiveness in removing pollutants and recovering water. Special attention is given to hybrid systems integrating membrane bioreactors (MBRs) and other advanced processes to enhance fouling control, improve water quality, and promote sustainability. Several case studies and quantitative data have demonstrated the reduction of chemical oxygen demand (COD), total suspended solids (TSS), and biological oxygen demand (BOD), illustrating the impact of these technologies. This comprehensive review also explores recent advancements, such as the integration of Zero Liquid Discharge (ZLD) processes, providing insights into the benefits and challenges of membrane technology for POME treatment. This article aims to inform future research and guide industrial applications toward more sustainable and efficient wastewater management in the palm oil industry.

The role of direct air capture in achieving climate-neutral aviation

Growing demand for air travel and limited scalable solutions pose significant challenges to the mitigation of aviation’s climate change impact. Direct air capture (DAC) may gain prominence due to its versatile applications for either carbon removal (direct air carbon capture and storage, DACCS) or synthetic fuel production (direct air carbon capture and utilization, DACCU). Through a comprehensive and time-dynamic techno-economic assessment, we explore the conditions for synthetic fuels from DACCU to become cost-competitive with an emit-and-remove strategy based on DACCS under 2050 CO2 and climate neutrality targets. We find that synthetic fuels could achieve climate neutrality at lower cost than an emit-and-remove strategy due to their ability to cost-effectively mitigate contrails. Under demand reductions, contrail avoidance, and CO2 neutrality targets the cost advantage of synthetic fuels weakens or disappears. Low electricity cost (€0.02 kWh-1) and high fossil kerosene prices (€0.9 l-1) can favor synthetic fuels’ cost-competitiveness even under these conditions. Strategic interventions, such as optimal siting and the elimination of fossil fuel subsidies, can thus favor a shift away from fossil-reliant aviation.

Optimizing COD reduction in dairy wastewater treatment using magnetic coagulant derived from Moringa oleifera

In wastewater treatment scenarios, traditional coagulants are becoming increasingly complex and raising environmental concerns. This has led to the exploration of magnetized plant-derived coagulant as an alternative. In this paper, coagulation parameters such as coagulant dosage and pH were optimized through response surface methodology (RSM) based on a central composite design (CCD) employing a magnetic coagulant derived from Moringa oleifera seeds (M. oleifera–CoFe2O4). The optimized response variable during the treatment of dairy wastewater was the chemical oxygen demand (COD) reduction. The response surface methodology revealed a statistically significant second-order polynomial model (R2 99.24%) for maximizing COD reduction. The maximum COD reduction achieved was 76.13% under optimal conditions with coagulant dosage of 14.24 g/L and pH of 9.38. The results indicated that magnetic coagulant derived from M. oleifera seeds demonstrated significant potential and can be used in an efficient and eco-friendly process for dairy wastewater treatment. Keywords: coagulation, dairy wastewater, flocculation, magnetic coagulant, Moringa Oleifera.

Preparation and characterization of Ru-TiO2/PC/Fe3O4 composite catalyst with enhanced photocatalytic performance and magnetic recoverability under simulated solar light.

This research focuses on the development of a novel Ru-doped TiO2/grapefruit peel biochar/Fe3O4 (Ru-TiO2/PC/Fe3O4) composite catalyst, which exhibits exceptional photocatalytic efficacy under simulated solar light irradiation. The catalyst is highly effective in the degradation of rhodamine B (RhB), methylene blue (MB), methyl orange (MO), as well as actual industrial dye wastewater (IDW), and can be recovered magnetically for multiple reuse cycles. Significantly, the PCTRF-100 sample exhibited degradation efficiencies of 99.4% for RhB and 99.8% for MB within 60 min, and 98.04% for MO within 120 min. In the case of actual dye wastewater, a reduction in chemical oxygen demand from 1540 mg L-1 to 784 mg L-1 was achieved within 300 min, corresponding to a degradation rate of 46.81%. The remarkable photocatalytic activity observed is primarily attributed to the synergistic interactions among Ru-TiO2, biochar, and Fe3O4, which effectively facilitate the separation and migration of electron-hole pairs in TiO2.

Enhanced removal of emerging recalcitrant pharmaceutical contaminants through integrated anaerobic and photocatalytic treatment

This study integrated anaerobic digestion (AD) and heterogenous photocatalysis, an advanced oxidation process (AOP), to treat tetracycline (TC), an emerging recalcitrant contaminant. The integrated system comprising an annular photocatalytic reactor and bioreactor was fed with simulated wastewater containing TC. The photocatalytic treatment was aided by a nano-engineered composite catalyst containing titanium dioxide (TiO2) and multi-wall carbon nanotubes (MWCNT). Heterogeneous photocatalysis as a single approach resulted in 90% TC degradation, 39% chemical oxygen demand (COD) reduction, 28% total organic carbon (TOC) removal, and minimal biochemical oxygen demand (BOD5) reduction. AD on its own removed 56% and 52%, respectively of the COD and BOD5. When applied as a pretreatment, heterogenous photocatalysis improved the biodegradability (BOD5/COD ratio) from 0.12 to 0.42 resulting in improved COD, BOD5, and TOC removals of 71%, 70%, and 76%, respectively in the ensuing AD process. Kinetic studies revealed that the ratio of the photocatalytic reactor unit to the anaerobic reactor unit for an integrated system with constant feed flow should be 12:1. Photodegradation as the only form of treatment used more energy than the integrated approach. The bioenergy generated by AD could supply the energy needs of the sequential system resulting in 20% energy savings and a carbon dioxide emission reduction (CER) of 22.74 kg for every cubic meter of treated wastewater. An integrated AOP-AD approach is thus promising for treating recalcitrant organic contaminants of emerging concern.

Electrodialysis with Bipolar Membranes to valorise saline waste streams: Analysing the fate of valuable minor elements.

Brine mining can represent a valuable non-conventional resource for the extraction of Mg, Li, B, Sr and other Trace Elements (TEs) such as Rb, Cs, whose recoveries require chemical reagents such as alkaline and acidic solutions. In a circular strategy, these required chemicals can be produced in-situ through Electrodialysis with Bipolar Membranes (EDBM). In this work, a laboratory EDBM unit was operated using real brines from Trapani saltworks to investigate, for the first time, the migration of minor and trace ions, as Li, B, Sr, Cs and Rb through ion-exchange membranes (IEMs). Two different operating configurations were tested by feeding real brines: i) only in the salt channel or ii) in both salt and alkaline compartments. Trace ions migration was assessed by determining their apparent transport number in IEMs to better understanding their "fate" within the EDBM process. The use of real solutions in the base channel resulted in a 50% reduction in the process water demand, while achieving similar overall Current Efficiencies (75-78%) and Specific Energy Consumptions (1.50-1.80 kWh/kgNaOH) compared to the reference layout, where real brine was only fed in the salt compartment. Li, Rb, Sr and Cs were mostly transported across the cation-exchange membrane and concentrated in the alkaline channel. Such results lay the ground for the use of complex (multi-ionic) solutions and new designs of the EDBM process that can be operated in integrated chains to valorise saline wastes, reducing water consumption and avoiding the dilution of trace elements before their selective recovery.

Study of electrocatalytic CO2 reduction using tin-oxalate organometallic frameworks doped with cadmium

The electrochemical reduction of CO2 demands highly effective catalysts due to the molecule’s inherent stability. Depending on the catalyst’s performance and selectivity, a range of products can be generated, from...

Enhancing wastewater treatment efficiency through hydrodynamic cavitation and advanced oxidation processes: Experimental insights and comparative analysis

BackgroundThe escalating industrial wastewater production mandates effective treatment methods to mitigate environmental and health risks. Hydrodynamic cavitation (HC) and its combination with advanced oxidation processes (AOPs) offer promising approaches for wastewater pollution reduction. MethodsThis study investigates the enhancement of HC efficiency for Chemical Oxygen Demand (COD) reduction by integrating hydrogen peroxide (H2O2) and air injection. Synthetic wastewater resembling industrial effluent COD levels serves as the experimental medium. Varied inlet pressures, H2O2 concentrations, and air injection rates were examined to gauge their impact on COD reduction. Significant FindingsHigher inlet pressures directly correlate with increased COD reduction, highlighting intensified cavitation effects. Combining HC with H2O2 or air, especially when directly injected into the venturi throat, showcased substantial synergy, significantly reducing COD levels. Notably, the maximum extent of COD reduction, achieved at 51.85 %, was with the combination of (HC+H2O2+Air). The COD reduction percentages for other processes, including HC alone, (HC+Air tank injection), (HC+Air throat injection), (HC+H2O2 tank injection), and (HC+H2O2 throat injection), were 4.21 %, 19.7 %, 20.9 %, 37.8 %, and 39.4 %, respectively.

Environmental impacts of restructuring the EU's natural gas supply and consumption: Learnings from the 2022 energy crisis.

In 2022, the European Union put forward the REPowerEU plan in response to Russia's invasion of Ukraine, aiming at enhancing short-term energy security by diversifying imports and reducing natural gas demand while accelerating the deployment of renewable alternatives in the long term. Here, we quantify the life cycle environmental impacts of both REPowerEU's short-term measures, including the controversial extended coal-fired power plant operations, and how the first year of the crisis was managed in practice. We find that the policy measures' impact on greenhouse gas (GHG) emissions would be negligible, although they could have detrimental effects on other environmental categories. In practice, GHG emissions dropped by 8.6% driven by energy savings, yet other environmental burdens worsened, primarily due to coal and oil use. Our results could support the development and analysis of long-term policies to enhance energy security via natural gas demand reduction while considering multiple environmental sustainability indicators to avoid collateral damage.

Independent aggregation in the nordic day-ahead market: What is the welfare impact of socializing supplier compensation payments?

This paper addresses the participation of independent aggregators (IAs) for demand response (DR) in European electricity markets. An IA is an aggregator trading the flexibility of consumers of which it is not the electricity supplier. Particularly, we focus on the controversial issue of a compensation payment from the IA to the supplier for energy sourcing. Concretely, we explore the potential welfare impacts of partial or full socialization of the compensation payment. For this, a static simulation framework is introduced utilizing historical day-ahead market bid and offer data from the Nordic region to rerun market clearing under different scenarios of compensation rules and with diverse assumptions regarding the DR aggregated by IAs. The overall welfare impacts comprise of changes in producer and consumer surplus, DR consumer welfare impact and the socialized part of the compensation. Based on a case study utilizing data for the full year of 2018, it is found that subsidizing the participation of IAs in the day-ahead market leads to negative overall welfare impacts due to over-incentivization of demand reduction. However, in nearly all investigated cases the socialization of the compensation payment leads to positive impacts on the consumer surplus, driven by reduced electricity wholesale prices. The optimal share of the socialization of the compensation that leads to the highest net consumer benefit depends on many factors, among which the assumptions around activation costs of DR are the most evident. Nevertheless, we argue that the socialization of the supplier compensation should be at least conditional upon the level of the hourly wholesale price (i.e., a "threshold price") and on DR cost estimates. Only in the case when high shares of untapped DR are relatively cheap, net welfare benefits will result.

Wastewater management by using effective phytoremediator duckweed

Water pollution and the increasing discharge of untreated wastewater into natural water bodies are intensifying the pressure on aquatic environments. Sustainable and eco-friendly methods are essential for restoring water quality and mitigating pollution. One such approach is water phytoremediation, which involves the use of aquatic plants to remove pollutants from water bodies and ecosystems. This study explored the removal of contaminants from municipal wastewater using floating aquatic plants such as Lemna minor, which have proven highly effective for phytoremediation due to their low cost, high pollutant uptake capacity, minimal generation of chemical and biological sludge, ease of transport, adaptability to diverse climatic conditions, and rapid reproduction rates. Notable findings from the research include reductions in chemical oxygen demand (COD) by 82.2%, biological oxygen demand (BOD) by 84.3%, phosphates by 63.8%, ammonium nitrogen by 75.4%, and nitrates by 79.1% for Lemna minor. Maximum plant growth occurred during the experiment at pH levels between 7 and 8. The study demonstrated that large-scale remediation could be effectively achieved using Lemna minor as a phytoremediation agent within 17 days. This method offers a cost-effective, efficient tertiary treatment for heavily polluted wastewater. Additionally, it can serve as an independent treatment solution when integrated with preliminary wastewater treatment systems in smaller communities.

Lifestyle changes overweighing technology improvement in household decarbonization: evidence from Japan during 1990-2020

Given that over 70% of global greenhouse gas emissions (GHG) stem from consumption, it is essential to promote lifestyle changes among end users and reduce emissions embedded in the upstream supply chain. We investigated the long-term (1990-2020) changes in household carbon footprints from such final users in Japan. Through factor decomposition, we found that the contribution of increasingly green technologies to household decarbonization is diminishing with time. In contrast, lifestyle changes - such as the shift to green products and services, as well as a reduction in overall demand - are becoming the main driver. Additionally, unlike most developed countries, the share of GHG emissions from food expenditures in Japan does not show a declining trend, highlighting the need to upgrade the domestic food supply chain and promote smart services for decarbonizing both homemade meals and eat-out preferences. Our long-term database can provide references to encourage sustainable behaviors and help Japanese policymakers evaluate the effectiveness of current efforts.

Ergonomics in Laparoscopic Box Training and Virtual Reality (VR) Simulations: A Systematic Review.

Laparoscopic surgery has now become the gold standard in managing most surgical cases. Despite its advantages, working hours and in-theatre training restrictions have prompted trainees to explore alternatives like virtual reality (VR) simulations and box training. Furthermore, given the increased frequency of minimally invasive surgery and the prevalence of musculoskeletal issues among surgeons, there's a growing effort to optimize ergonomics. There is currently a lack of focus on ergonomics in training, prompting our study to inspect VR and box training's ergonomic outcomes and their impact on task performance. This systematic review was conducted at Barts Cancer Institute, Queen Mary University, from January 27, 2024, to April 22, 2024. Multiple databases were searched electronically from January 1980 to March 2024, including only articles that utilized electromyography (EMG) or the NASA Task Load Index (NASA-TLX) to measure ergonomics. Two reviewers independently conducted eligibility assessment, data extraction, and risk of bias evaluation, with discrepancies resolved through consensus discussions. Ultimately, 12 studies were selected. EMG results indicated a higher %MVC (maximum voluntary contraction) in box training in poor ergonomic settings and a negative correlation between skills and muscle activity. Both modalities showed a significant decrease in NASA-TLX scores after training on the simulators and when comparing novice and experienced surgeons. Furthermore, a reduction in physical demand and improved task performance was observed, with significant differences found between experts and novices in a VR appendicectomy scenario. This systematic review reveals reduced muscle activity and physical demand among trained individuals in laparoscopic surgery with both box trainers and VR simulators, emphasizing the importance of addressing ergonomic considerations. To advance our understanding of surgical ergonomics, the standardization of measurement methods and higher-quality evidence, particularly through randomized controlled trials, are recommended.

Decarbonization pathways promote improvements in cement quality and reduce the environmental impact of China’s cement industry

The cement industry plays a key role in emission reduction efforts, but cement quality is rarely considered in low-carbon development analyses. Here we design three cement quality transformation routes in response to China’s cement quality improvement program and analyse the corresponding low-carbon development pathways via a bottom-up integrated assessment model. Results show that cement quality improvements trigger a 14.6% increase in energy consumption and emissions in business-as-usual scenarios in 2060. Compared with the base year, raising the environmental taxes to 46.8 Chinese Yuan per equivalent unit saves up to 75.1% of carbon dioxide emissions and 25.0% of fuel consumption from the high-quality-cement scenario by 2060. Carbon capture and storage contributes up to 77% of the emission reduction. The reduction in cement demand conserves 17.3% more energy than the high-cement-demand scenario does in 2060. Collaborative waste treatment is expected to replace 22.4% of fuel consumption in the cement industry in 2060.