G. Lepage, G. Perrier, G. Merlin et al.

RSC Adv. • 2014

A lab-scale microbial fuel cell (MFC) with a reticulated vitreous carbon (RVC) anode and a non-catalyzed multi-layered carbon air-cathode was electrochemically characterized under various physicochemical factors: temperature (15–25 °C), phosphate buffer concentration (4–8 mM), acetate concentration (7.1–14.3 mM), and equivalent solution conductivity (2.5–5 mS cm −1 ).

J. Barrett, S. Pye, Sam Betts-Davies et al.

Nature Energy • 2022

In recent years, global studies have attempted to understand the contribution that energy demand reduction could make to climate mitigation efforts. Here we develop a bottom-up, whole-system framework that comprehensively estimates the potential for energy demand reduction at a country level. Replicable for other countries, our framework is applied to the case of the United Kingdom where we find that reductions in energy demand of 52% by 2050 compared with 2020 levels are possible without compromising on citizens’ quality of life. This translates to annual energy demands of 40 GJ per person, compared with the current Organisation for Economic Co-operation and Development average of 116 GJ and the global average of 55 GJ. Our findings show that energy demand reduction can reduce reliance on high-risk carbon dioxide removal technologies, has moderate investment requirements and allows space for ratcheting up climate ambition. We conclude that national climate policy should increasingly develop and integrate energy demand reduction measures. Efforts to model the contribution of energy demand reductions towards climate targets typically focus at the global scale. Here, Barrett et al. develop an approach for understanding the country-level demand reduction potential and explore options for lowering final energy demand in the United Kingdom.

Haifeng Liu, J. Ampah, Yang Zhao et al.

Energies • 2022

Arguably, one of the most important issues the world is facing currently is climate change. At the current rate of fossil fuel consumption, the world is heading towards extreme levels of global temperature rise if immediate actions are not taken. Transforming the current energy system from one largely based on fossil fuels to a carbon-neutral one requires unprecedented speed. Based on the current state of development, direct electrification of the future energy system alone is technically challenging and not enough, especially in hard-to-abate sectors like heavy industry, road trucking, international shipping, and aviation. This leaves a considerable demand for alternative carbon-neutral fuels such as green ammonia and hydrogen and renewable methanol. From this perspective, we discuss the overarching roles of each fuel in reaching net zero emission within the next three decades. The challenges and future directions associated with the fuels conclude the current perspective paper.

P. Plötz, Jakob Wachsmuth, F. Sprei et al.

Climate Policy • 2023

ABSTRACT Following the Paris Agreement, virtually all countries worldwide have committed themselves to undertaking efforts to limit global warming to 1.5 °C. Within the European Union (EU), the recent ‘Fit for 55’ policy package proposes ambitious greenhouse gas (GHG) mitigation policies for all sectors as part of the EU's contribution to limiting global warming. Yet, it is unclear whether the proposed policies are sufficient for the EU to limit global warming to 1.5 °C and it remains an open policy problem how to translate global temperature targets into sector-specific emission budgets and further into sector-specific policies. Here, we derive GHG budgets for transport in EU27 and obtain GHG mitigation pathways for Europe consistent with 1.5 °C global warming. We do not provide a comprehensive assessment of the ‘Fit for 55’ transport package but we discuss the main policies for road transport in light of the GHG emission budgets, their level of ambition, and suggest amendments to these policies as well as improvements to the ‘Fit for 55’ package. Our results suggest that parts of the ‘Fit for 55’ for transport are still not ambitious enough to align with a 1.5 °C scenario. Key policy insights A Paris-compatible residual carbon budget for EU transport is 10–12 Gt CO2. The budget implies net zero emissions for EU transport by 2044–2048 latest. We find the current ‘Fit for 55’ proposal for transport is not ambitious enough. A faster phase-out of cars and trucks with combustion engines is required and there is a need for ambitious standards for fast charging e-vehicles. CO2 pricing of transport is not a substitute but a complement to fleet targets.

Gresia Putri Damayanti, Waluyo Waluyo, Rosita Candrakirana

PLEDOI (Jurnal Hukum dan Keadilan) • 2023

The goal of this paper is to conduct a normative analysis of the PLTSa development in Indonesia as a form of net-zero emissions policy. This research is normative and conducted through library research utilizing the statute approach method. It is done by looking normatively at the relevant statutory regulations. So, utilizing the theory developed by Hans Kelsen and Nawiasky, known as the stufenbau theory, he concentrates on the discussion of statutory regulations connected to PLTSa development in the discussion part and the study findings. Examining if different legal frameworks governing PLTSa development in Indonesia are harmonized is the goal. Additionally, the discussion and research findings in this paper draw on studies of the literature from a range of sources that address the integration of the Sustainable Development Goals (SDGs) and the principles of Good Environmental Governance in Indonesia's PLTSa development plans. According to the research in this paper, it can be concluded that PLTSa development in Indonesia can positively influence efforts to achieve net zero emissions, and that PLTSa use in waste management is a form of environmental protection that is consistent with the objectives of sustainable development. In order to develop and administer PLTSa in Indonesia, the government still needs to take into account a number of factors, starting with the implementation of these policies and statutory regulations. in order for the PLTSa policy optimization to work effectively.

K. Doering, C. Anderson, S. Steinschneider

Oxford Open Energy • 2023

Rapid increases in global temperature are motivating governments to restructure the energy sector towards emissions-free electricity generation. One of the key factors affecting the viability of emissions-free power systems is the joint variability of renewable resources and drivers of energy demand across spatiotemporal scales. This study evaluates the impact of multi-scale hydroclimatic variability on the reliability of a zero-emissions power system in a case study of New York State (NYS), which recently passed the Climate Leadership and Community Protection Act (CLCPA) requiring zero-emissions electricity generation by 2040. We first analyze covariation between renewable energy generation and energy demand, including large-scale hydropower generation on the Great Lakes, and develop a stochastic generator to simulate an ensemble of plausible realizations of this joint variability. Using a simplified energy balance model of the NYS power system, we then quantify resource gaps across spatiotemporal scales that emerge under load and generation scenarios projected under the CLCPA. We focus on the intensity, duration, and frequency of these gaps, which will have to be filled with carbon-free, dispatchable resources not prescribed under the CLCPA. We show that the covariability between load and wind can lead to major short-term resource gaps, which is exacerbated by transmission constraints. We also show that long-duration hydropower droughts increase the likelihood of co-occurring renewable resource deficits and extended periods (weeks to months) of energy shortage. We conclude by discussing the implications of these results on the need for alternative, carbon-free, and dispatchable resources to support zero-emission, hydropower-reliant electric grids.

Hamed Kouchaki-Penchah, O. Bahn, Kathleen Vaillancourt et al.

Environmental Science & Technology • 2023

Global pathways limiting warming to 2 °C or below require deep carbon dioxide removal through a large-scale transformation of the land surface, an increase in forest cover, and the deployment of negative emission technologies (NETs). Government initiatives endorse bioenergy as an alternative, carbon-neutral energy source for fossil fuels. However, this carbon neutral assumption is increasingly being questioned, with several studies indicating that it may result in accounting errors and biased decision-making. To address this growing issue, we use a carbon budget model combined with an energy system model. We show that including forest sequestration in the energy system model alleviates the decarbonization effort. We discuss how a forest management strategy with a high sequestration capacity reduces the need for expensive negative emission technologies. This study indicates the necessity of establishing the most promising forest management strategy before investing in bioenergy with carbon capture and storage. Finally, we describe how a carbon neutrality assumption may lead to biased decision-making because it allows the model to use more biomass without being constrained by biogenic CO2 emissions. The risk of biased decision-making is higher for regions that have lower forest coverage, since available forest sequestration cannot sink biogenic emissions in the short term, and importing bioenergy could worsen the situation.

J. Ampah, Sandylove Afrane, H. Adun et al.

Environmental Research Letters • 2024

As the remaining carbon budget for limiting warming to 1.5 °C rapidly diminishes, it is clear that, besides decarbonization, the world will need to remove 100–1000 GtCO2 from the atmosphere by the end of the century. Yet, Africa, where many carbon removal schemes are planned, remains a ‘blindspot’ in existing studies. There is limited understanding of the trade-offs and synergies associated with carbon removal within Africa’s energy-land-water system. To address this research gap, we model a stylized net-zero emissions (NZEs) in Africa by 2050, with focus on three land-based biological carbon removal approaches: afforestation/reforestation (AR), bioenergy with carbon capture and storage (BECCS), and biochar. We find that by 2050, the total gross carbon removal is projected to reach 1.2 GtCO2 yr−1 when all three carbon removal approaches are available, and 0.5 GtCO2 yr−1 when Africa relies solely on AR. Pursuing NZE with only AR or AR alongside biochar in Africa would be the most expensive mitigation option but they lead to the lowest residual fossil fuel and industry CO2 emissions. An NZE by 2050 in Africa could reduce cropland by 30%–40% from 2020 to 2050, depending on the carbon dioxide removal deployment strategy adopted. Southern Africa would be particularly affected, facing significant challenges in balancing food security with climate goals. The highest increase in staple food prices will occur under AR only, while the availability of AR-BECCS-biochar produces the lowest rise in staple food prices. Our findings highlight the need for balanced and region-specific carbon dioxide removal strategies to ensure climate and other sustainability goals are met.

Vicky Firmansyah, Made Krisna Adinarayana, R. Tetrisyanda et al.

E3S Web of Conferences • 2023

In 2011, Indonesia set a 26% reduction goal for greenhouse gas emissions by 2030 to mitigate the climate change. Based on data from BPS, Indonesia's renewable energy mix in 2021 is 12.16% with a target of 23% in 2025. This indicates that there are challenges faced by Indonesia in many sectors, especially the upstream oil and gas industry as one of the largest emitters of greenhouse gases, in achieving the energy transition target. In this study, trend analysis and data forecasting were carried out using trend analysis of time series data on oil and gas energy supply and consumption data as baseline to propose scenarios for both consumption and utilization energy to achieve net zero emission (NZE) in 2060. This study found that NZE may be achieved by applying energy consumption scenarios including the use of electric vehicles by 10% in 2030, and 90% in 2060 and the use of electric stoves by 25% in 2030, and 90% in 2060. Renewable energy utilization scenarios include geothermal (50%), hydro (50%), mini hydro (50%), solar (80%), and wind (15%) of the existing potential. In addition, early retirement for coal-fired power plants is needed.

W. Sparber, Andrea Grotto, P. Zambelli et al.

World Electric Vehicle Journal • 2023

Public bus decarbonization is increasingly important to address the global issue of climate change. There are several challenges associated with large-scale introduction of zero-emission technologies in public fleets. This is especially the case in an extra-urban context, of mountain regions with challenging weather conditions. In this work the analysis of the state-of-the-art ZEBs, local bus lines, and timetables was performed to understand the best fit of technology—battery electric buses (BEBs) or fuel cell electric buses (FCEBs)—for each line in such a region. Further, a simulation tool was developed to calculate the compatibility of zero-emission technologies with the current needs of the public transportation considering distance, altitude difference, and climate conditions. The results show that a complete switch of the fleet is possible with a slight increase in the number of buses and that there is no clear difference in the distance covered in mountainous areas by BEBs versus FCEBs, but that both technologies can cover similar distances. The tool developed is not limited to bus fleets but can be applied to all kinds of fleets that cover clearly defined daily routes.

Dirk J Smit, J. B. Powell

Annual Review of Chemical and Biomolecular Engineering • 2023

Scientific and engineering capabilities in hydrocarbon supply chains developed over decades in international oil and gas companies (IOCs) uniquely position these companies to drive rapid scale-up and transition to a net zero emission (NZE) economy. Flexible large-scale production of energy carriers such as hydrogen, ammonia, methanol, and other synthetic fuels produced with low- or zero-emission renewable power, nuclear energy, or hydrogen derived from natural gas with carbon capture and storage will enable long-distance transport and permanent storage options for clean energy. Use of energy carriers can overcome the inherent constraints of a fully electrified energy system by providing the energy and power densities, as well as transport and storage capacity required to achieve energy supply and security in a net zero emission economy, and over time allow optimization to the lowest cost for a consumer anywhere on the globe. Expected final online publication date for the Annual Review of Chemical and Biomolecular Engineering, Volume 14 is June 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Kai Zhang, Xiaojuan Lei, Caiqing Mo et al.

Advanced Science • 2023

High indoor humidity/temperature pose serious public health threat and hinder industrial productivity, thus adversely impairing the wellness and economy of the entire society. Traditional air conditioning systems for dehumidification and cooling involve significant energy consumption and have accelerated the greenhouse effect. Here, this work demonstrates an asymmetric bilayer cellulose‐based fabric that enables solar‐driven continuous indoor dehumidification, transpiration‐driven power generation, and passive radiative cooling using the same textile without any energy input. The multimode fabric (ABMTF) consists of a cellulose moisture absorption–evaporation layer (ADF) and a cellulose acetate (CA) radiation layer. The ABMTF exhibits a high moisture absorption capacity and water evaporation rate, which quickly reduces the indoor relative humidity (RH) to a comfortable level (40–60% RH) under 1 sun illumination. The evaporation‐driven continuous capillary flow generates a maximum open‐circuit voltage (Voc) of 0.82 V, and a power density (P) up to 1.13 µW cm−3. When a CA layer with high solar reflection and mid‐infrared (mid‐IR) emissivity faces outward, it realizes subambient cooling of ≈12 °C with average cooling power of ≈106 W m−2 at midday under radiation of 900 W m−2. This work brings a new perspective to develop the next‐generation, high performance environmentally friendly materials for sustainable moisture/thermal management and self‐powered applications.

Orfeas Karountzos, Georgios Kagkelis, K. Kepaptsoglou

Journal of Geovisualization and Spatial Analysis • 2023

Sustainability of maritime operations is a topic widely considered in recent years, as the shipping industry attempts to limit its environmental impact and meet the decarbonization goals set by the International Maritime Organization (IMO). As alternative fuels and newer ship technologies are gaining interest, the shift to more environmentally friendly fleets is quickly becoming a reality. In this context, potential areas for such shifts need to be determined, to expedite decarbonization efforts and provide passengers with a more sustainable way of travel. Greece is an insular country, with a complex coastal shipping network connecting the mainland with the islands and being of paramount importance for their economic growth. Recognizing accessibility and decarbonization needs, this paper examines whether the Greek coastal shipping network (GCSN) can be restructured, by introducing zero-emission sub-networks operated by electric ferries. The aim is to propose a methodological framework for the spatial analysis and evaluation of coastal networks, with the implementation of exploratory spatial data analysis (ESDA) methods and determination of local indicators of spatial association (LISA) with the help of geographic information systems (GIS). The proposed framework provides insight on whether and where such a restructuring is possible, with the introduction of new transshipment port hubs in the islands from which electric ferries could operate, thus determining potential electrification areas with additionally high renewable resource potential. Final conclusions indicate that a potential electrification of certain parts of the GCSN could be possible, while results for GHG emissions reduced by the introduction of electric ferries are calculated.

E. Van Rheenen, J. T. Padding, J. Slootweg et al.

Journal of Marine Engineering & Technology • 2023

Green hydrogen combined with PEM fuel cell systems is a viable option to meet the demand for alternative maritime fuels. However, hydrogen storage faces challenges, including low volumetric density, fire and explosion risks and transport challenges. We assessed over fifteen hydrogen carriers based on their maritime performance characteristics to determine their suitability for shipboard use. Evaluation criteria included energy density, locally zero-emission, circularity of process, safety, dehydrogenation process, logistic availability and handling. Thus, excluding ammonia and methanol because of these constraints, we found that borohydrides, liquid organic hydrogen carriers and ammoniaborane are the most promising hydrogen carriers to use on ships with PEM fuel cells. Borohydrides, specifically sodium borohydride, have high energy densities but face regeneration issues. The liquid organic hydrogen carrier dibenzyltoluene has a lower energy density but exhibits easy hydrogenation and good handling. Given varying operational demands, we developed a framework to assess the suitability of hydrogen carriers for use in different ship categories. Evaluating the three types of hydrogen carriers, using our framework and considering current practices, shows that these are viable options for almost all ship types. Thus, we have identified three types of hydrogen carriers, which should be the focus of future research.

Gihan Gamage, Nishan Mills, Daswin De Silva et al.

2024 IEEE International Conference on Industrial Technology (ICIT) • 2024

Modern energy platforms are increasingly leveraging Artificial Intelligence (AI) for effective decision-making and efficient operations. This has led to the development of expansive data spaces that comprise both structured and unstructured energy data in various modalities. Conversational agents with the most recent advancements in Large Language Models (LLM) are primed to facilitate the efficient retrieval of this diverse information for decision support. In this paper, we propose a multi-agent chatbot architecture for decision support in net-zero emissions energy systems, leveraging LLMs and Retrieval-Augmented Generation (RAG). This architecture consists of a Chatbot User Interface (UI), an advanced Natural Language Understanding (NLU) module for precise entity and intent recognition, a robust Chatbot Core with four specialized agents: Observer, Knowledge Retriever, Behavior Analyzer, and Visualizer and Response Construction Module. These components work together to address diverse decision support needs in energy environments, specifically for net zero carbon emissions initiatives that need to consider diverse parameters and large volumes of data. We showcase the chatbot's successful integration and evaluation for decision support in the net-zero emissions energy system of a large tertiary education institution.

Priyanka Saha, Faysal Ahamed Akash, Shaik Muntasir Shovon et al.

International Journal of Green Energy • 2023

ABSTRACT Energy is the linchpin for economic development despite its generation deficit worldwide. Hydrogen can be used as an alternative energy source to meet the requirement that it emits zero to near-zero impurities and is safe for the environment and humans. Because of growing greenhouse gas emissions and the fast-expanding usage of renewable energy sources in power production in recent years, interest in hydrogen is resurging. Hydrogen may be utilized as a renewable energy storage, stabilizing the entire power system and assisting in the decarbonization of the power system, particularly in the industrial and transportation sectors. The main goal of this study is to describe several methods of producing hydrogen based on the principal energy sources utilized. Moreover, the financial and ecological outcomes of three key hydrogen colors (gray, blue, and green) are discussed. Hydrogen’s future prosperity is heavily reliant on technology advancement and cost reductions, along with future objectives and related legislation. This research might be improved by developing new hydrogen production methods, novel hydrogen storage systems, infrastructure, and carbon-free hydrogen generation. GRAPHICAL ABSTRACT

A. Saha, V. Šimić, Tapan Senapati et al.

IEEE Transactions on Fuzzy Systems • 2023

For the first time, the critical worldwide problem of prioritizing zero-emission last-mile delivery (LMD) solutions for sustainable city logistics is addressed and solved in this article. It not only aims to help city logistics companies sustainably decarbonize urban freight distribution but also provide valuable practical guidelines. To evaluate zero-emission LMD solutions, this article presents a novel multicriteria group decision-making methodology with dual hesitant fuzzy (DHF) sets. First, we propose some improved operations on DHF elements and investigate their vital properties. Second, based on these operations, we develop DHF improved weighted averaging operator to overcome the drawbacks of the existing operators on DHF sets. Third, for measuring the weights of criteria, a new model called the cross-entropy-based optimization model (CEBOM) is developed. Fourth, for the rational aggregation of the preferences, we formulate a new method namely score-based double normalized measurement alternatives and ranking according to the compromise solution (SDNMARCOS). The proposed DNMARCOS method couples the linear and vector normalization techniques. It is composed of the complete compensatory model and the incomplete compensatory model. Thus, SDNMARCOS is more robust compared to the available state-of-the-art approaches. To exhibit the applicability of the proposed DHF-CEBOM-SDNMARCOS methodology in real-world settings, a case study for one of the largest Austrian logistics companies in Serbia is provided. The research findings show that electric light commercial vehicles are the best LMD solution. Also, it is recommended to consider electric cargo bikes as a viable mid-term solution. The superiority of the introduced methodology is demonstrated through the comparative investigation.

Yati Nurhayati, Ifrani, M. Said et al.

Environmental Policy and Law • 2024

The Nationally Determined Contribution (NDC) of Indonesia in the Paris Agreement targeted emission reductions of 29% on its own and 41% with international cooperation in 2030, followed by Net Zero Emissions (NZE) in 2060. To achieve NZE, Indonesia enacted a carbon tax policy on April 1, 2022. The 2022–2024 carbon tax is limited to Steam Power Plants and will be imposed on other sectors by 2030. This research examines the ratio legis of carbon cost policies in Indonesia and compares the core of carbon tax policies in Indonesia with Sweden and Finland. Indonesia is starting to implement a Carbon Pricing policy under the ‘Cap-and-Tax’ scheme. The Cap scheme will be a means to force changes in the business culture in Indonesia, so the companies will pay attention to and reduce the carbon emission produced to avoid paying penalties for carbon exceeding the limits. Meanwhile, the Carbon Tax will provide economic resources to Indonesia to develop environmentally friendly technologies, fund research on renewable energy, and provide incentives for environmentally friendly businesses during the transition process to a carbon culture in Indonesia. Referring to the results of the comparison of carbon pricing policies in Finland and Sweden, Indonesia can gradually increase the cost of carbon taxes starting from Rp30,000/US$2 per ton CO2 equivalent to US$10 per ton CO2 equivalent. Meanwhile, for the imposition of high carbon tax rates, such as in Finland (US$73.02 per ton CO2 equivalent) and Sweden (US$137 per ton CO2 equivalent), Indonesia must carry out tax reforms, so the applied carbon tax is able to reduce carbon emissions without causing adverse impacts for the Indonesian economy.

Namireddy Praveen Reddy, R. Skjetne, Oliver Stugard Os et al.

IEEE Journal of Emerging and Selected Topics in Industrial Electronics • 2024

Zero-emission ships (ZESs) have gained interest to comply with the stringent regulations of international maritime organization. One way to build ZES is the hybridization of fuel cells with batteries. Traditionally, for a newly built ship, the energy and emissions management system (EEMS) is designed based on the initial condition of the fuel cells and batteries and used with fixed parameters in future execution. However, for a fuel cell and battery ZES, the EEMS gradually becomes suboptimal since the characteristics of fuel cells and batteries are continuously changing due to aging and degradation. In this article, a reinforcement learning (RL)-based EEMS is developed such that it can learn and adapt continuously to changes in the fuel cell/battery characteristics. Within RL, different types of algorithms, such as double deep $Q$ -learning (DDQL), soft actor–critic (SAC), and proximal policy optimization (PPO) are implemented. The results are benchmarked against those of a typical rule-based EEMS. Each RL algorithm is trained with four reward function formulations; negative cost ( $r_{1}$ ), negative quadratic cost ( $r_{2}$ ), inverse cost ( $r_{3}$ ), and inverse quadratic cost ( $r_{4}$ ). The results demonstrate that health-aware EEMS can minimize fuel consumption and component degradation costs. $r_{1}$ has led to the lowest operational expenses (OPEX) followed by $r_{2}$ , while $r_{3}$ and $r_{4}$ have high OPEX. Among the three algorithms, the DDQL led to the lowest reward followed by the SAC and then the PPO, when trained with $r_{1}$ and $r_{2}$ .

Hui Li, Zhouyang Ren, Anupam Trivedi et al.

IEEE Transactions on Smart Grid • 2024

This paper proposes an optimal planning method for the dual-zero microgrid (DZMG) on an island. The DZMG is the off-grid microgrid that exchanges zero power with entity grids and operates in a net-zero carbon emission mode. A net-zero emission operating strategy is designed considering the positive interaction between $\rm CO_{2}$ flow and energy flow. The multi-scale circulation of $\rm CO_{2}$ flow is realized by coordinating the carbon capture system, solvent storage tank (SST), and direct air capture (DAC), while the seasonal shift of energy flow is completed by the hydrogen storage system (HSS) and DAC. An optimization planning model for DZMG is developed to size the SST, DAC, and HSS optimally. The net-zero emission target and the net-zero operating strategy are involved in the model to balance the environmental and economic concerns in the planning. Numerical experiments are carried out on two IEEE test systems and a real-world island microgrid to validate the effectiveness and adaptability of the proposed method. Simulation results reveal that the proposed method reduces the planning cost by over 25% compared with the extant zero-carbon-based method. Besides, the economy of the DZMG positively correlates to carbon prices and technological maturity, while inversely relates to fuel prices.

Kaiqi Jiang, Hai Yu, Zening Sun et al.

Environmental Science & Technology • 2024

Decarbonization of the cement sector is essentially required to achieve carbon neutrality to combat climate change. Amine-based CO2 capture is a leading and practical technology to deeply remove CO2 from the cement industry, owing to its high retrofittability to existing cement plants and extensive engineering experience in industrial flue gas decarbonization. While research efforts have been made to achieve low-carbon cement with 90% CO2 removal, a net-zero-emission cement plant that will be required for a carbon neutrality society has not yet been investigated. The present study proposed an advanced amine-based CO2 capture system integrated with a cement plant to achieve net-zero CO2 emission by pushing the CO2 capture efficiency to 99.7%. Monoethanomaine (MEA) and piperazine/2-amino-2-methyl-1-propanol (PZ-AMP) amine systems, which are considered to be the first- and second-generation capture agents, respectively, were detailed investigated to deeply decarbonize the cement plant. Compared to MEA, the advanced PZ-AMP system exhibited excellent energy performance with a regeneration duty of ∼2.6 GJ/tonne CO2 at 99.7% capture, 39% lower than the MEA process. This enabled a low CO2 avoided cost of $72.0/tonne CO2, which was 18% lower than that of the MEA-based zero-emission process and even 16.2% lower than the standard 90% MEA process. Sensitivity analysis revealed that the zero-emission capture cost of the PZ-AMP system would be further reduced to below $56/tonne CO2 at a $4/GJ steam production cost, indicating its economic competitiveness among various CO2 capture technologies to achieve a zero-emission cement plant.

V. Aryanpur, F. Rogan

Scientific Reports • 2024

The road freight sector faces significant challenges in decarbonisation, driven by high energy demand and limited availability of low-emission fuels and commercialised zero-emission vehicles. This study investigates intangible costs associated with advanced electric and hydrogen-powered trucks, including recharging/refuelling time, cargo capacity limitations, and buyer reluctance towards emerging technologies. Utilising a comprehensive whole-systems modelling approach considering low- and zero-emission fuels, inter-sectoral dynamics, and the carbon budget, we explore cost-optimal decarbonisation pathways for heavy, medium, and light trucks. Scenario and sensitivity analyses reveal the following insights: (1) Electric trucks dominate the market under mitigation pathways across all weight categories. However, the inclusion of intangible costs triggers a shift, leading to the emergence of hydrogen fuel cell vehicles for heavy trucks, while battery electric vehicles are preferred for medium and small trucks. (2) Prioritising heavy truck decarbonisation and taking early action are crucial to avoid carbon lock-in effects. (3) Considering limited decarbonisation options, where electric and hydrogen-fuelled trucks are pivotal, this research highlights the significance of policy instruments targeting operational expenditures over conventional purchase price incentives. Such policies offer dual benefits by supporting truck owners and directing incentives more precisely towards achieving measurable emission reductions.

Sirine Saadaoui, B. Erable, Luc Etchevery et al.

Fermentation • 2023

Bioelectrochemical systems (BESs), rather than physicochemical processes, are used for wastewater remediation, electricity production, and zero carbon dioxide emission. Textile effluents contain organic and inorganic compounds that can fuel BESs. The main goal of this study was to understand the interplay between the anode material, its surface area, the potential applied to the working electrode (WE), and the concentration of the co-substrate, and how these factors lead to the formation of highly efficient thermohalophilic bioanodes (THB) retrieved from Chott El Djerid (SCD) hypersaline sediment for the treatment of synthetic textile wastewater. To this end, twenty-seven bioanode formation experiments were designed using a Box-Behnken matrix and response surface methodology to understand concomitant interactions. All experiments were conducted in electrochemical reactors of final volume 750 mL inoculated with 80% of enrichment medium containing three azo dyes at a concentration of 300 ppm and 20% of biocatalyst microbial SCD source, at 45 °C. The optimal levels were predicted using NemrodW software as carbon felt (CF) anode material, 6 cm2 anode surface, 7 g/L glucose concentration, and −0.1 V applied potential. These theoretical results were experimentally validated, using maximum current output of 5.23 ± 0.30 A/m2, decolorization rate of 100%, and a chemical oxygen demand (COD) removal rate of 96 ± 1%. Illumina Miseq results revealed that bacterial community harbored the bioanode was dominated at phylum level by Firmicutes (67.1%). At the species level, the biofilm was mainly colonized by Orenia metallireducens species (59.5%). Obtained findings show a promising application of THB in the degradation of recalcitrant molecules as well as for the energy recovery.

Arian Loli, Chiara Bertolin

Buildings • 2018

Nowadays, restoration interventions that aim for minimum environmental impact are conceived for recent buildings. Greenhouse gas emissions are reduced using criteria met within a life-cycle analysis, while energy saving is achieved with cost-effective retrofitting actions that secure higher benefits in terms of comfort. However, conservation, restoration and retrofitting interventions in historic buildings do not have the same objectives as in modern buildings. Additional requirements have to be followed, such as the use of materials compatible with the original and the preservation of authenticity to ensure historic, artistic, cultural and social values over time. The paper presents a systematic review—at the intersection between environmental sustainability and conservation—of the state of the art of current methodological approaches applied in the sustainable refurbishment of historic buildings. It identifies research gaps in the field and highlights the paradox seen in the Scandinavian countries that are models in applying environmentally sustainable policies but still poor in integrating preservation issues.

Piotr F. Borowski

Energies • 2025

The energy transition requires substantial financial investments and the adoption of innovative technological solutions. The aim of this paper is to analyze the economic and technological aspects of implementing zero-emission strategies as a key component of the transition toward a carbon-neutral economy. The study assesses the costs, benefits, and challenges of these strategies, with a particular focus on wind farms and nuclear power, including small modular reactors (SMRs). The paper presents an in-depth examination of key examples, including onshore and offshore wind farms, as well as nuclear energy from both large-scale and small modular reactors. It highlights their construction and operating costs, associated benefits, and challenges. The investment required to generate 1 MW of energy varies significantly depending on the technology: onshore wind farms range from $1,300,000 to $2,100,000, offshore wind farms from $3,000,000 to $5,500,000, traditional nuclear power plants from $3,000,000 to $5,000,000, while small modular reactors (SMRs) require between $5,000,000 and $10,000,000 per MW. The discussion underscores the critical role of wind farms in diversifying renewable energy sources while addressing the high capital requirements and technical complexities of nuclear power, including both traditional large-scale reactors and emerging SMRs. By evaluating these energy solutions, the article contributes to a broader understanding of the economic and technological challenges essential for advancing a sustainable energy future.

Thorsten Schuetze

Sustainability • 2015

This paper discusses the history, status quo, and future prospects of Zero Emission Buildings (ZEBs) in the Republic of Korea. The advantages of, and requirements for ZEBs are described, concerning the factors of energy, water, nutrients, and biomass. ZEBs are characterized by net zero energy consumption through the minimization of the energy demand, as well as the onsite production and use of renewable energy. The direct water footprint is reduced by up to 100% through on-site water supply and wastewater management according to the principles of Sustainable Sanitation. The fresh water demand is reduced by using water saving technologies and by recycling of wastewater. Rainwater harvesting, utilization, and infiltration facilitates for onsite drinking water production. Nutrients and biomass from sanitation systems are recycled for local soil application. While traditional Korean buildings can be generally regarded as ZEBs, traditional know-how has been overlooked in the process of modernization and implementation of centralized infrastructure systems in the 20th century. However, the growing interest in sustainability issues in Korea since the beginning of the 21st century is reflected in a growing number of research and development activities, including the design, construction, and operation of ZEBs. The widespread implementation of ZEBs would significantly contribute to sustainable development in the Republic of Korea.

Deger Saygin, Dolf Gielen

Energies • 2021

The chemical and petrochemical sector relies on fossil fuels and feedstocks, and is a major source of carbon dioxide (CO2) emissions. The techno-economic potential of 20 decarbonisation options is assessed. While previous analyses focus on the production processes, this analysis covers the full product life cycle CO2 emissions. The analysis elaborates the carbon accounting complexity that results from the non-energy use of fossil fuels, and highlights the importance of strategies that consider the carbon stored in synthetic organic products—an aspect that warrants more attention in long-term energy scenarios and strategies. Average mitigation costs in the sector would amount to 64 United States dollars (USD) per tonne of CO2 for full decarbonisation in 2050. The rapidly declining renewables cost is one main cause for this low-cost estimate. Renewable energy supply solutions, in combination with electrification, account for 40% of total emissions reductions. Annual biomass use grows to 1.3 gigatonnes; green hydrogen electrolyser capacity grows to 2435 gigawatts and recycling rates increase six-fold, while product demand is reduced by a third, compared to the reference case. CO2 capture, storage and use equals 30% of the total decarbonisation effort (1.49 gigatonnes per year), where about one-third of the captured CO2 is of biogenic origin. Circular economy concepts, including recycling, account for 16%, while energy efficiency accounts for 12% of the decarbonisation needed. Achieving full decarbonisation in this sector will increase energy and feedstock costs by more than 35%. The analysis shows the importance of renewables-based solutions, accounting for more than half of the total emissions reduction potential, which was higher than previous estimates.

Justin Kramer, Anjaneyulu Krothapalli, Brenton Greska

ASME 2007 Energy Sustainability Conference • 2007

This paper deals with the Off-Grid Zero Emissions Building (OGZEB), a project undertaken by the Sustainable Energy Science & Engineering Center (SESEC) at Florida State University (FSU). The project involves the design, construction and operation of a completely solar-powered building that achieves LEED-NC (Leadership in Energy and Environment Design-New Construction) platinum certification. The resulting 1000 square foot building will be partitioned such that 750 square feet will be a two bedroom, graduate student style flat with the remaining 250 square feet serving as office space. This arrangement will allow the building to serve as an energy efficient model for campus designers in student living and office space. The building will also serve as a prototype for developing and implementing cutting edge, alternative energy technologies in both residential and commercial settings. For example, hydrogen will be used extensively in meeting the energy needs of the OGZEB. In lieu of high efficiency batteries, the excess electricity produced by the building’s photovoltaic (PV) panels will be used to generate hydrogen via water electrolysis. The hydrogen will be stored on-site until needed for either generating electricity in a Proton Exchange Membrane (PEM) fuel cell stack or combusted in natural gas appliances that have been modified for hydrogen use. Although commercial variants already exist, a highly efficient water electrolysis device and innovative PEM fuel cell are currently under development at SESEC and both will be implemented into the OGZEB. The use of hydrogen in modified natural gas appliances, such as an on-demand hot water heater and cook top, is unique to the OGZEB.

Mikko Pihlatie, Mikaela Ranta, Pekka Rahkola et al.

Preprints.org • 2023

Zero-emission trucks for regional and long haul missions are an option for fossil-free freight. The viability of such powertrains and system solutions was studied conceptually in project ESCALATE for trucks with GVW of 40 tonnes and beyond through various prime mover combinations. The study covers battery and fuel cell power sources with different degrees of battery electric as well as H2 and fuel cell operation. As a design basis, two different missions with a single-charge/H2 refill were analysed. The first mission was the VECTO long haul profile repeated up to 750 km, whereas the second was a real 520 km on-road mission in Finland. Based on the simulated energy consumption on the driving cycle, on-board energy demand was estimated, and the initial single-charge operational scenarios were analysed with five different power source topologies. The traction motors of the tractor were dimensioned so that a secondary mission of GVW up to 76 tons on a shorter route can be operated. Based on the powertrain and vehicle model, various infrastructure options for charging and H2 refuelling strategy as well as various operative scenarios with indicative total cost of ownership (TCO) were analysed.

Piotr F. Borowski, Barbara Karlikowska

Energies • 2023

Hydrogen can be considered an innovative fuel that will revolutionize the energy sector and enable even more complete use of the potential of renewable sources. The aim of the paper is to present the challenges faced by companies and economies that will produce and use hydrogen. Thanks to the use of hydrogen in the energy, transport and construction sectors, it will be possible to achieve climate neutrality by 2050. By 2050, global demand for hydrogen will increase to 614 million metric tons a year, and thanks to the use of hydrogen in energy, transport and construction, it will be possible to achieve climate neutrality. Depending on the method of hydrogen production, the processes used and the final effects, several groups can be distinguished, marked with different colors. It is in this area of obtaining friendly hydrogen that innovative possibilities for its production open up. The costs of hydrogen production are also affected by network fees, national tax systems, availability and prices of carbon capture, utilization, and storage installations, energy consumption rates by electrolyzers and transport methods. It is planned that 1 kg of hydrogen will cost USD 1. The study used the desk research method, which made it possible to analyze a huge amount of descriptive data and numerical data.

Modeste Kameni Nematchoua, Sigrid Reiter

Zero-Energy Buildings - New Approaches and Technologies • 2020

The buildings respecting the concept “Net Zero energy” are becoming more and more flowering in the world these last years. The main goal of this research is to evaluate the different possibilities of implementation of buildings with Net zero energy and low environmental impacts in Sub-Saharan Africa. The proposed building is 80% made of local materials with low carbon emissions and especially at lower cost. The optimization and modeling of the building is carried out by the Design Builder software, which is a world-renowned software in the field of optimization of comfort, cost, carbon reduction, etc. By fixing the insulation thickness up to 11 cm, cooling and heating energy are found equal to zero during the different operating seasons in this residential building. The results show that the optimal solution to consider a net zero energy building in Antananarivo city requires an additional expense estimated at 40% of the cost of buildings more conventional encountered in the island. This will save $475 each year starting in 2030, with 99% reduction in the CO2 release. The choice of local materials with low conductivity, low emissions, and low cost, has a significant impact on the implementation of a sustainable building, and more adapted to climate change concept.

Shah Ali Adnan, Akanksha .

ADHYAYAN: A JOURNAL OF MANAGEMENT SCIENCES • 2023

Every other day we hear about environmental and climate issues and the effect of global warming or carbon emission. Many companies are shifting their concerns from making profits to making sustainable profits. The idea of saving the environment has propelled many start-ups also. Organizations worldwide are concerned about the consequences of wasting natural resources and trying their best to find a solution as soon as possible. The Paris Agreement and the Net Zero Coalition are some of the treaties the UN organization is trying to implement. The problem is that some people are ignoring climate change altogether or still think this is not a big concern. So, this article answers the following questions: what is net zero or net zero emission, how does it create an impact on our lives, and what, as an individual, do we could do about it?

A. Sharma

Water Science and Technology • 2003

Innovative application of a systematic approach to reduce freshwater intake and achieve zero emissions could help in reducing the adverse impact of industrial activity on world water resources. Cleantech is a strategic enviro-management technique to reduce the generation of pollutants in a process at source, through minor process modification, material substitution, improved manufacturing practices or low cost treatment.

Devi Bühler, Thorsten Schuetze, Ranka Junge

Sustainability • 2015

The operation of so-called Zero Emission Buildings (ZEB) does not result in harmful emissions to water, soil and air. In contrast, ZEBs produce energy, water and resources. Therefore, the definition of ZEBs in this paper goes well beyond the definition of (Net) Zero Energy Buildings, which focuses primarily on greenhouse gas emissions resulting from the combustion of fossil fuels. The concept of ZEB is based on the decentralization of urban infrastructure systems on the building level. The aim is to avoid environmental impacts during the building operation through sustainable production, management, consumption, and recycling of resources. In order to facilitate an easy evaluation of ZEBs a ZEB assessment tool needed to be developed. This paper discusses the development of the general framework, the assessment method, and the ZEB Assessment Tool (ZEBAT), which facilitates the evaluation of the environmental performance of potential ZEBs. The exemplary evaluation of selected case studies from Switzerland and South Korea illustrates the method and the practicability of the ZEBAT for the evaluation of potential ZEBs. The holistic integration of environmental performance factors and their specific environmental impacts facilitates the successful application of the ZEBAT independently from the specific use of a building and its geographical location.

M. E. M. Hassouna, Marzooka Shaban Abdel‐Tawab, Adel Ahmed Mohamed Abdel‐Aleem

Environmental Quality Management • 2024

Phenol bioremediation was investigated using two bacteria (primarily cocci) Dermacoccus nishinomiyaensis, Kocuria rosea strains and the one actinomycetes Nocardiopsis lucentensis which were isolated from samples of activated sludge from the wastewater treatment plant (WWTP) in Beni‐Suef, Egypt as sole carbon and energy sources. This was applied on real industrial wastewater sample taken from Ul HAWA textile plant, Middle Egypt. Degradation of phenol by microbes adsorbed on natural kaolin clay was studied compared with free microbes. In case of 50 mg/L as starting phenol concentration, the percentage removal using free microbes was 68%, corresponding to 98% in case of microbes adsorbed on kaolin clay after the passage of 48 h under incubation at 30°C and neutral pH at 150 rpm. Also, 300 mg/L of phenol achieved degradation frequency of 80% compared to 38% after ≈48 h without clay addition. High concentrations of an organic pollutant are usually inhibitory for the microorganisms. Kaolin clay has a pronounced effect in accelerating phenol degradation through biofilm formation resulting in decreasing the degradation time, increasing the percentage of removing efficiency under high phenol concentration conditions due to its buffering effects on pH fluctuations of the degradation system. Kaolin clay protects microorganisms against unfavorable environment, resists the adverse effects of substrate inhibition and accelerates the degradation process. The adsorption process was demonstrated by the pseudo‐first‐order, pseudo‐second‐order, Weber–Morris adsorption kinetic models, and four isotherm models namely, Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich have been applied to express the adsorption process. The SEM images of microbes adsorbed on kaolin clay explain their adsorption mode on the clay surface as biofilm (Bio kaolinite).

María E. Alcamán-Arias, C. Pedrós-Alió, J. Tamames et al.

Frontiers in Microbiology • 2018

Composition, carbon and nitrogen uptake, and gene transcription of microbial mat communities in Porcelana neutral hot spring (Northern Chilean Patagonia) were analyzed using metagenomics, metatranscriptomics and isotopically labeled carbon (H13CO3) and nitrogen (15NH4Cl and K15NO3) assimilation rates. The microbial mat community included 31 phyla, of which only Cyanobacteria and Chloroflexi were dominant. At 58°C both phyla co-occurred, with similar contributions in relative abundances in metagenomes and total transcriptional activity. At 66°C, filamentous anoxygenic phototrophic Chloroflexi were >90% responsible for the total transcriptional activity recovered, while Cyanobacteria contributed most metagenomics and metatranscriptomics reads at 48°C. According to such reads, phototrophy was carried out both through oxygenic photosynthesis by Cyanobacteria (mostly Mastigocladus) and anoxygenic phototrophy due mainly to Chloroflexi. Inorganic carbon assimilation through the Calvin–Benson cycle was almost exclusively due to Mastigocladus, which was the main primary producer at lower temperatures. Two other CO2 fixation pathways were active at certain times and temperatures as indicated by transcripts: 3-hydroxypropionate (3-HP) bi-cycle due to Chloroflexi and 3-hydroxypropionate-4-hydroxybutyrate (HH) cycle carried out by Thaumarchaeota. The active transcription of the genes involved in these C-fixation pathways correlated with high in situ determined carbon fixation rates. In situ measurements of ammonia assimilation and nitrogen fixation (exclusively attributed to Cyanobacteria and mostly to Mastigocladus sp.) showed these were the most important nitrogen acquisition pathways at 58 and 48°C. At 66°C ammonia oxidation genes were actively transcribed (mostly due to Thaumarchaeota). Reads indicated that denitrification was present as a nitrogen sink at all temperatures and that dissimilatory nitrate reduction to ammonia (DNRA) contributed very little. The combination of metagenomic and metatranscriptomic analysis with in situ assimilation rates, allowed the reconstruction of day and night carbon and nitrogen assimilation pathways together with the contribution of keystone microorganisms in this natural hot spring microbial mat.

Haobo Ya, Tian-Shu Zhang, Yi Xing et al.

SSRN Electronic Journal • 2023

Microplastics are plastic particles with particle size less than 5 mm in the environment. As an emerging organic pollutant, the presence of microplastics in the soil environment has been widely noticed. Secondly, due to the overuse of antibiotics, a large amount of antibiotics that cannot be fully absorbed by humans and livestock enter the soil environment in the form of urine or manure, making the soil suffer from serious antibiotic contamination problems. To address the environmental problems of microplastics and antibiotic contamination in soil, this study was conducted to investigate the effects of PE microplastics on antibiotic degradation, microbial community characteristics and ARGs in tetracycline-contaminated soils. The results showed that the addition of PE microplastics inhibited the degradation of tetracycline, and significantly increased the organic carbon content and decreased the neutral phosphatase activity. The addition of PE microplastics significantly reduced the alpha diversity of soil microbial community. Compared to the single tetracycline contamination. In addition, combined contamination with PE microplastics and tetracycline significantly affected bacterial genera such as Aeromicrobium, Rhodococcus, Mycobacterium and Intrasporangium. Metagenome sequencing studies revealed that the addition of PE microplastics inhibited the dissipation of ARGs in tetracycline-contaminated soils. There were strong positive correlations between Multidrug, Aminoglycoside and Clycopeptide resistance genes and Chloroflexi and Proteobacteria in tetracycline contaminated soils, and there was a strong positive correlation between Aminoglycoside resistance genes and Actinobacteria in combined contamination of PE microplastics and tetracycline. This study will provide some data support for the current environmental risk assessment of the coexistence of multiple contaminants in soil.

Anjali Chandrol Solanki, N. Gurjar, Satish Sharma et al.

Frontiers in Microbiology • 2024

In dry deciduous tropical forests, both seasons (winter and summer) offer habitats that are essential ecologically. How these seasonal changes affect soil properties and microbial communities is not yet fully understood. This study aimed to investigate the influence of seasonal fluctuations on soil characteristics and microbial populations. The soil moisture content dramatically increases in the summer. However, the soil pH only gradually shifts from acidic to slightly neutral. During the summer, electrical conductivity (EC) values range from 0.62 to 1.03 ds m-1, in contrast to their decline in the winter. The levels of soil macronutrients and micronutrients increase during the summer, as does the quantity of soil organic carbon (SOC). A two-way ANOVA analysis reveals limited impacts of seasonal fluctuations and specific geographic locations on the amounts of accessible nitrogen (N) and phosphorus (P). Moreover, dehydrogenase, nitrate reductase, and urease activities rise in the summer, while chitinase, protease, and acid phosphatase activities are more pronounced in the winter. The soil microbes were identified in both seasons through 16S rRNA and ITS (Internal Transcribed Spacer) gene sequencing. Results revealed Proteobacteria and Ascomycota as predominant bacterial and fungal phyla. However, Bacillus, Pseudomonas, and Burkholderia are dominant bacterial genera, and Aspergillus, Alternaria, and Trichoderma are dominant fungal genera in the forest soil samples. Dominant bacterial and fungal genera may play a role in essential ecosystem services such as soil health management and nutrient cycling. In both seasons, clear relationships exist between soil properties, including pH, moisture, iron (Fe), zinc (Zn), and microbial diversity. Enzymatic activities and microbial shift relate positively with soil parameters. This study highlights robust soil-microbial interactions that persist mainly in the top layers of tropical dry deciduous forests in the summer and winter seasons. It provides insights into the responses of soil-microbial communities to seasonal changes, advancing our understanding of ecosystem dynamics and biodiversity preservation.

Kriangsak Ketpang, A. Boonkitkoson, Nattawan Pitipuech et al.

E3S Web of Conferences • 2020

The major technical obstacles in commercialization of microbial fuel cell technology are the sluggish kinetic, high cost, and poor durability of an air cathode electrocatalyst. This research aimed to synthesize the highly active, stable and low cost non-precious metal catalyst to replace the expensive Pt electrocatalyst using a simple, low cost and scalable method. The Fe3C and Fe-N-C catalysts were prepared by direct heating the precursors under autogenic pressure conditions. X-ray diffraction pattern revealed the phase of Fe3C sample was cohenite Fe3C and graphitic carbon, while the phase of Fe-N-C catalyst was only graphitic carbon. The morphology of the synthesized catalysts was a highly porous structure with nanoparticle morphology. The surface area of the Fe3C and the Fe-N-C catalysts was 295 and 377 m2 g-1, respectively. The oxygen reduction reaction (ORR) activity of Fe-N-C catalyst was more active than Fe3C catalyst. The ORR performance of Fe-N-C catalyst exhibited about 1.6 times more superior to that of the noble Pt/C catalyst. In addition, the Fe-N-C catalyst was durable to operate under neutral media. Thus, a novel autogenic pressure technique was a promising method to effectively prepare an highly active and durable non-precious metal catalyst to replace the precious Pt/C catalyst.

A. Mentges, C. Deutsch, C. Feenders et al.

Frontiers in Marine Science • 2020

Dissolved organic carbon (DOC) forms one of the largest active organic carbon reservoirs on Earth and reaches average radiocarbon ages of several thousand years. Many previous large scale DOC models assume different lability classes (labile to refractory) with prescribed, globally constant decay rates. In contrast, we assume that all DOC compounds are equally degradable by a heterotrophic microbial community. Based on this central assumption, we simulate DOC concentrations using a simple biogeochemical box model. Parameterized correctly, the simple model of neutral DOC uptake produced a recalcitrant carbon pool of 33 mmolC/m3, throughout the entire virtual ocean. The spatial distribution of DOC in the model was independent of the distribution of DOC sources from primary production and particle degradation. Instead, DOC concentrations were primarily driven by spatial gradients in microbial physiology, e.g., mortality rate or growth efficiency. Applying such a gradient, we find DOC concentrations of ~70 mmolC/m3 at the surface and ~35 mmolC/m3 in the deep ocean. Introducing model variations, such as seasonally-varying supply rates or temperature-dependent DOC uptake did not significantly alter model results. DOC spatial patterns are thus not necessarily shaped by the co-cycling of separate reactivity fractions, but can also arise from gradients in physiological parameters determining DOC uptake. We conclude that neutral DOC uptake can lead to realistic large-scale patterns of DOC concentration in the ocean.