Carbon Energy Sources Research Articles

Risk Retirement—Decreasing Uncertainty and Informing Consenting Processes for Marine Renewable Energy Development

Marine renewable energy (MRE) is under development in many coastal nations, adding to the portfolio of low carbon energy sources that power national electricity grids as well as off-grid uses in isolated areas and at sea. Progress in establishing the MRE industry, largely wave and tidal energy, has been slowed in part due to uncertainty about environmental risks of these devices, including harm to marine animals and habitats, and the associated concerns of regulators and stakeholders. A process for risk retirement was developed to organize and apply knowledge in a strategic manner that considered whether specific environmental effects are likely to cause harm. The risk retirement process was tested against two key MRE stressors: effects of underwater noise from operational MRE devices on marine animals, and effects of electromagnetic fields from MRE electrical export cables on marine animals. The effects of installation of MRE devices were not accounted for in this analysis. Applying the risk retirement process could decrease the need for costly investigations of each potential effect at every new MRE project site and help move the industry beyond current barriers.

3‐Hydroxypicolinic Acid as an Effective Matrix for Sophorolipid Structural Elucidation Using Matrix‐Assisted Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry

AbstractDetermination of the distribution of sophorolipid (SL) congeners controls their self‐assembly structures and therefore their employment as glycolipid biosurfactants in cosmetics, environmental remediation, and personal care applications. The compatibility of 3‐hydroxypicolinic acid (HPA) as a matrix for compositional analysis of SL using palm olein as carbon energy source by matrix‐assisted laser desorption ionization time of flight mass spectrometry (MALDI‐TOF MS) analysis under positive and negative ion modes is studied in this work. Examination in positive ion mode revealed ions that were not detected in negative ion mode. Molecular ions produced using HPA matrix were lactonic Glc‐Glc‐1′,4″‐C18:1, anionic Glc‐Glc‐1′‐C18:1, lactonic monoacetate of Glc‐Glc‐1′,4″‐C18:1, and anionic monoacetate Glc‐Glc‐1′‐C18:1 and the anionic diacetate of Glc‐Glc‐1′‐C18:1. We also detected Glc‐Glc‐1′‐C18:0, GlcOAc‐Glc‐1′‐C18:0, GlcOAc‐GlcOAc‐1′,4″‐C18:0, and GlcOAc—GlcOAc‐1′‐C18:0 which are congeners of SL with stearic acid moieties. 3‐HPA has been established to be the superior matrix for elucidation of structures for SL using MALDI‐TOF MS.

Dissolved organic matter in a tropical saline-alkaline lake of the East African Rift Valley.

Saline-alkaline lakes of the East African Rift are known to have an extremely high primary production supporting a potent carbon cycle. To date, a full description of carbon pools in these lakes is still missing. More specifically, there is not detailed information on the quality of dissolved organic matter (DOM), the main carbon energy source for heterotrophs prokaryotes. We report the first exhaustive description of DOM molecular properties in the water column of a meromictic saline-alkaline lake of the East African Rift. DOM availability, fate and origin were studied either quantitatively, in terms of dissolved organic carbon (DOC) and nitrogen (DON) or qualitatively, in terms of optical properties (absorbance) and molecular characterization of solid-phase extracted DOM (SPE-DOM) through negative electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). DOM availability was high (DOC ∼ 8.1 mM in surface waters) and meromixis imprinted a severe quantitative and qualitative change on DOM pool. At the surface, DOM was rich in aliphatic and moderately in aromatic molecules and thus mirroring autochthonous microbial production together with photodegradation. At the bottom changes were extreme: DOC increased up to 5 times (up to 50 mM) and, molecular signature drifted to saturated, reduced and non-aromatic DOM suggesting intense microbial activity within organic sediments. At the chemocline, DOC was retained indicating that this interface is a highly reactive layer in terms of DOM processing. These findings underline that saline-alkaline lakes of the East African Rift are carbon processing hot spots and their investigation may broaden our understanding of carbon cycling in inland waters at large.

NEGOTIATING ENERGY DIPLOMACY AND ITS RELATIONSHIP WITH FOREIGN POLICY AND NATIONAL SECURITY

Energy diplomacy is a complex field of international relations, closely linked to its principal, foreign policy and overall national security. We observe the relationship of issues that belong to the three concepts and how they are intertwined in the geopolitical reality. Despite the ontological hierarchy of the three concepts, where national security is on the highest level of generality, and energy diplomacy on the lowest, it is a recurring theme for them to continuously meet and intersect in realpolitik in a dynamic relationship. The article specifically looks at the integration of energy diplomacy into foreign policy. We discuss two pathways that energy diplomacy has taken on its integration course into foreign policy, namely the path marked by national security topics and the path that is dominantly an economic one. The article also observes the nexus of national security, foreign policy, economic security and economic diplomacy, which is termed the energy security paradox. It exemplifies the inconsistencies in the general state of affairs in which resource riches of a country result in a stable exporter status and consequentially, stable exporting energy diplomacy. The recommendation for further research is suggested, directed at the new dynamics of the relation of energy transition and energy diplomacy. Research could facilitate in understanding or envisaging how new low carbon energy sources coupled with energy efficiency will influence the new geopolitical map, affecting energy diplomacy in the geopolitical context where geography will have a lesser dominance on international relations. Keywords: Diplomacy, Energy Diplomacy, Foreign Policy, National Security JEL Classifications : F5, O13, P32 DOI: https://doi.org/10.32479/ijeep.8754

Diverse and common features of trehalases and their contributions to microbial trehalose metabolism.

Trehalose is a stable disaccharide that consists of two glucose units linked primarily by an α,α-(1 → 1)-linkage, and it has been found in a wide variety of organisms. In these organisms, trehalose functions not only as a source of carbon energy but also as a protector against various stress conditions. In addition, this disaccharide is attractive for use in a wide range of applications due to its bioactivities. In trehalose metabolism, direct trehalose-hydrolyzing enzymes are known as trehalases, which have been reported for bacteria, archaea, and eukaryotes, and are classified into glycoside hydrolase 37 (GH37), GH65, and GH15 families according to the Carbohydrate-Active enZyme (CAZy) database. The catalytic domains (CDs) of these enzymes commonly share (α/α)6-barrel structures and have two amino acid residues, Asp and/or Glu, that function as catalytic residues in an inverting mechanism. In this review, I focus on diverse and common features of trehalases within different GH families and their contributions to microbial trehalose metabolism.

Unilateral Co2 Reduction Policy with More than One Carbon Energy Source

We examine an open economy’s strategy to reduce its carbon emissions by replacing its consumption of coal—very carbon intensive—with gas—less so. Unlike the standard theoretical approach to carbon leakage, we show that unilateral CO2 reduction policies generate a higher leakage rate in the presence of more than one carbon energy source, and may turn counterproductive, ultimately increasing world emissions. We establish testable conditions as to whether a unilateral tax on domestic CO2 emissions increases the domestic exploitation of gas, and whether such a strategy increases global emissions. We also characterize this strategy’s implications for climate policy in the rest of the world. Finally, we present an illustrative application of our results to the US.

Characterisation of salmonid food webs in the rivers and lakes of an Irish peatland ecosystem

Peatlands are being degraded by the combined impacts of land use and climate change. Carbon stored in peat is a key constituent of aquatic food webs in rivers and lakes of humic catchments, and changes in the downstream transport of this allochthonous carbon may have considerable implications for the production of Atlantic salmon and brown trout. Understanding the food web of these keystone species is therefore crucial to their conservation in a changing world. Here, we use a combination of stomach content analysis (SCA) and stable isotope analysis (SIA) to characterise the diet of juvenile salmonids in aquatic habitats of a typical Irish peatland catchment (Burrishoole). SCA showed that Diptera, Ephemeroptera, Plecoptera and Trichoptera were the main components of the diet of juvenile salmonids. Daphnia were the primary prey item in salmon smolt stomachs. The average stable isotope signature of salmonids was 9.26 ± 0.87‰ δ 15N and -25.6 ± 1.99‰ δ13C, but differed between species, age class and habitat (river vs lake). Salmonids were supported by a wide range of carbon energy sources, with δ13C increasing as fish moved downstream out of the headwater rivers and into a large downstream lake.

Understanding community acceptance of a potential offshore wind energy project in different locations: An island-based analysis of ‘place-technology fit’

Understanding the factors influencing community acceptance of renewable energy projects such as offshore wind farms is important for achieving a transition to low carbon energy sources. However, to date community acceptance research has concentrated on responses to actual proposals, seeking to explain local objections. ‘Upstream’ research that investigates the ‘place-technology fit’ of a potential renewable energy project before it is proposed is scarce, yet can inform technology deployment by taking local knowledge and preferences into account. We address this gap in a study conducted in Guernsey, Channel Islands. Data was collected using a survey (n = 468) co-designed with island policy makers presenting technical, economic and locational details of a potential offshore wind project. Results show that acceptance of the same project design differed significantly across alternative development locations. Regression analyses compared the roles of personal, context and project-related factors in explaining acceptance for each site. Support for using wind energy for local electricity supply was the most important predictor of acceptance, and this variable mediated the relationship between island energy security and community acceptance. We conclude that place matters for community acceptance and that security and autonomy are co-benefits of local renewable energy projects that deserve further research.

Custom-Made Ion Exchange Membranes at Laboratory Scale for Reverse Electrodialysis.

Salinity gradient power is a renewable, non-intermittent, and neutral carbon energy source. Reverse electrodialysis is one of the most efficient and mature techniques that can harvest this energy from natural estuaries produced by the mixture of seawater and river water. For this, the development of cheap and suitable ion-exchange membranes is crucial for a harvest profitability energy from salinity gradients. In this work, both anion-exchange membrane and cation-exchange membrane based on poly(epichlorohydrin) and polyvinyl chloride, respectively, were synthesized at a laboratory scale (255 2) by way of a solvent evaporation technique. Anion-exchange membrane was surface modified with poly(ethylenimine) and glutaraldehyde, while cellulose acetate was used for the cation exchange membrane structural modification. Modified cation-exchange membrane showed an increase in surface hydrophilicity, ion transportation and permselectivity. Structural modification on the cation-exchange membrane was evidenced by scanning electron microscopy. For the modified anion exchange membrane, a decrease in swelling degree and an increase in both the ion exchange capacity and the fixed charge density suggests an improved performance over the unmodified membrane. Finally, the results obtained in both modified membranes suggest that an enhanced performance in blue energy generation can be expected from these membranes using the reverse electrodialysis technique.

Effect of Bioactive Water on the Biodegradation of Naphthalene Contaminated Soil

In this experiment, the strain NW6 with good growth of naphthalene as the sole carbon source and energy source was screened from petroleum contaminated soil after isolation and purification by enrichment culture. The influencing factors of strain were studied. The results showed that the optimum growth conditions for strain NW6 were pH 8, 40 °C. In the contaminated soil for sand, loess and black soil, the degradation rate of naphthalene by NW6 was 28.05%, 24.35% and 21.34% respectively. Adding bioactive water, the degradation rate was increased compared with distilled water. The enhanced rates of BW against strain NW6 in three naphthalene contaminated soils were respectively: sand 83.28%, loess 103.56%, black soil 60.40%. It showed that the bioactive water could promote the degradation of microorganisms.

Insights into Carbonate Fuel Cell Operation Under Carbon Dioxide Capture Conditions

Providing for increasing global energy needs while managing carbon dioxide emissions is the dual energy challenge the modern world faces. In order to meet this challenge, reliable and dispatchable low carbon energy sources are a likely component. For many scenarios, this suggests that cost effective carbon dioxide capture will be a key technology.[1] Carbon capture with carbonate fuel cells (CFCs) may be one such technology option.[2]Carbonate fuel cells concentrate carbon dioxide from the cathode to the anode as part of their normal operation, effectively doing both carbon capture and low carbon power generation in a single process. (see Figure 1) When generating power, typical carbon dioxide concentrations fed to the CFC cathode tend to be higher than carbon dioxide emissions of many industrial processes. This means that if we want to capture that carbon dioxide, we need the fuel cell to operate at lower carbon dioxide concentrations than it typically does. For carbon capture operations, cathode inlet carbon dioxide concentrations could be as low as 4%. Additionally, under typical power generation operations, CFCs only capture a fraction of the carbon dioxide (<50%) fed to the cathode, where for carbon capture rates may be as high as 90%. Together these two constraints (low initial concentration and higher capture) results in very low carbon dioxide concentrations in the cell, particularly at the cathode outlet. This may impact the fundamental chemistry of the process. Carbon dioxide capture at 4% and lower was tested in a fuel cell, specifically designed to minimize mass transport effects external to the active cell components. Carbon capture was demonstrated at a range of carbon dioxide concentrations ranging from standard operation for power generation (>10%) to <1%. Additionally, oxygen concentrations and current densities were varied over likely operational ranges. We demonstrate that under most circumstances, operations under carbon capture conditions proceed via a similar mechanism to those under power generation conditions. However, in harsh or extreme conditions, where carbon dioxide concentrations are low (<0.5%) and/or current densities high, alternative mechanisms appear. We demonstrate how the CFC performs when these alternative mechanisms are present. Additionally, our findings suggest that they appear to utilize water in place of carbon dioxide and allow the cell to operate at conditions beyond theoretical complete carbon capture. [1] IEA World Energy Outlook 2018; Bloomberg New Energy Finance, New Energy Outlook 2018 [2] Ghezel-Ayagh H., Jolly S., Patel D., Hunt J., Steen W., Richardson C., Marina O., (2013) A Novel System for Carbon Dioxide Capture Utilizing Electrochemical Membrane Technology ECS Transaction Vol 51 (1) 265-272 Figure 1

Characteristics of human-climate feedbacks differ at different radiative forcing levels

Abstract The human and Earth systems are intricately linked: Climate influences agricultural production, renewable energy potential, and water availability, for example, while anthropogenic emissions from industry and land use change alter temperature and precipitation. Such feedbacks have the potential to significantly alter future climate change. These feedbacks may also exert significant changes on 21st-century energy, agriculture, land use and carbon cycle projections, but little is known about their possible magnitudes, or about regional and sector dynamics under different forcing scenarios. Here we use an integrated Earth System Model (ESM) featuring bidirectional information exchange between an economically-oriented integrated assessment model and the ESM to examine how human-natural feedbacks operate under high and medium radiative forcing (RF) scenarios. Specifically, we examine the effect of changing land productivity on human systems, and the effect of changing land use/land cover and CO2 emissions on the Earth system. We find that the effect of coupling differs across radiative forcing levels and across regions, due to differences in the climate signal, human responses to those signals, and regional characteristics. In particular, we find reductions in cropland area due to feedbacks in both the medium and high RF scenarios. In the medium RF scenario, these reductions result in increased area for bioenergy and afforestation and reduced energy system CO2 emissions, as the carbon price in this scenario incentivizes low carbon energy sources and terrestrial carbon storage; these incentives are absent in the high RF scenario. These differences are key to understanding the possible future evolution pathways of the integrated Earth system in response to 21st century climate change. Additional models and hypothesis testing are needed to determine exactly when and how bidirectional feedbacks between human and Earth systems should be considered in future assessments.

Comparing how the public perceive CCS across Australia and China

Whilst carbon capture and storage (CCS) has been promoted as a direct countermeasure against global warming, there remains much debate about what its final role as a climate change mitigation strategy will be. One key criticism directed towards CCS has been its inability to gain public support. This study compares public attitudes to the range of low carbon energy sources and technologies across Australia and China, and is the first study to compare primary data across these two countries on this topic. An online survey encompassing a broad set of questions was used to identify the factors that are associated with support for CCS compared to other energy technologies. Data were collected from a nationally representative Australian sample (n = 2383) and from Chinese urban residents across six regions (n = 1266). The survey confirmed low levels of knowledge and support for CCS in both countries. However, male respondents, those who perceived themselves to have higher knowledge of CCS, and those who valued economic outcomes over environmental protection were more likely to support CCS - as long as the risks were not perceived to outweigh the benefits. The results found that for Australians who believed in human-induced climate change they were likely to be unsupportive of CCS. This opposition appears to be linked to no tolerance for extending fossil fuels as in our factor analysis CCS was aligned to fossil fuels in Australia. In both countries, support for renewable energy technologies remains strong. Given the International Energy Agency’s future energy demand projections, combined with slow progress towards meeting the Paris Climate Agreement, the lack of knowledge and support for CCS is concerning. While there have been some technological advances, without parallel improvements in public acceptance of CCS, it will be difficult to see any commercial projects going forward in the near future. Although, the Chinese government’s success in educating on climate science, as evidenced in these results, suggests that they may be more effective at informing the public of the benefits of CCS and take the lead on its deployment for climate change mitigation. Based on the latest climate models, it is almost crunch time for governments to decide if CCS has a role to play as part of an energy transition to a low carbon future or perhaps it may be time to turn their focus to climate adaptation.

Comparing How the Public Perceive CCs Across Australia and China

Abstract Whilst carbon capture and storage (CCS) has been promoted as a direct countermeasure against global warming, there remains much debate about what its final role as a climate change mitigation strategy will be. One key criticism directed towards CCS has been its inability to gain public support. This study compares public attitudes to the range of low carbon energy sources and technologies across Australia and China, and is the first study to compare primary data across these two countries on this topic. An online survey encompassing a broad set of questions was used to identify the factors that are associated with support for CCS compared to other energy technologies. Data were collected from a nationally representative Australian sample (n = 2383) and from Chinese urban residents across six regions (n = 1266). The survey confirmed low levels of knowledge and support for CCS in both countries. However, male respondents, those who perceived themselves to have higher knowledge of CCS, and those who valued economic outcomes over environmental protection were more likely to support CCS - as long as the risks were not perceived to outweigh the benefits. The results found that for Australians who believed in human-induced climate change they were likely to be unsupportive of CCS. This opposition appears to be linked to no tolerance for extending fossil fuels as in our factor analysis CCS was aligned to fossil fuels in Australia. In both countries, support for renewable energy technologies remains strong. Given the International Energy Agency’s future energy demand projections, combined with slow progress towards meeting the Paris Climate Agreement, the lack of knowledge and support for CCS is concerning. While there have been some technological advances, without parallel improvements in public acceptance of CCS, it will be difficult to see any commercial projects going forward in the near future. Although, the Chinese government’s success in educating on climate science, as evidenced in these results, suggests that they may be more effective at informing the public of the benefits of CCS and take the lead on its deployment for climate change mitigation. Based on the latest climate models, it is almost crunch time for governments to decide if CCS has a role to play as part of an energy transition to a low carbon future or perhaps it may be time to turn their focus to climate adaptation.

Projected climate change impacts on Indiana’s Energy demand and supply

This paper estimates changes in future energy demand and supply for Indiana due to projected climate change impacts. We first estimate demand changes under both the business-as-usual emissions scenario (RCP 8.5) and a scenario based on reduced emissions consistent with a 2-degree increase in global mean temperature (RCP 4.5), on both a statewide basis and for major urban areas. We then use our adjusted statewide energy demand projections as an input to a comprehensive model of Indiana’s energy system, to project expected changes in the state’s energy supply under both scenarios. Finally, we consider the potential impacts of two policy scenarios—a carbon pricing scheme and a renewable energy investment tax credit—on emissions and future energy supply choices. Our results suggest that climate change will have a relatively modest effect on energy demand and supply in Indiana, slightly increasing commercial demand and decreasing residential demand but having little effect on energy supply choices. In addition, our results suggest the potential for policy proposals currently being adopted in other states, such as a relatively small carbon price or investment credits for renewable energy sources, to have a larger impact on the state’s future energy mix, increasing production from low or zero carbon energy sources and reducing emissions.

Degradation of 17β-estradiol and products by a mixed culture of Rhodococcus equi DSSKP-R-001 and Comamonas testosteroni QYY20150409

In this study, we investigated environmental oestrogen 17β-estradiol (E2) degradation by a mixed culture of Rhodococcus equi DSSKP-R-001(RS) and Comamonas testosteroni QYY20150409(CT). The results demonstrated that the two strains exhibited synergistic E2 degradation activity, showing that multispecies bacterial systems can improve microbial survival and activity. The E2 degradation rate for the mixed culture system was 94% under conditions in which E2 was the sole source of carbon and growth energy, while the degradation rates of the R. equi DSSKP-R-001 and C. testosteroni QYY20150409 single strains were 86% and 76%, respectively. Comparing and analyzing the degradation products of E2, intermediate cross-metabolism products were observed in the culture containing the two bacteria. The metabolic products of benzene were essentially removed during the process of E2 degradation in the mixed culture, which showed stronger degradation ability than cultures of the individual strains. The results from this investigation on the degradation of E2 by individual and mixed bacterial cultures provide a theoretical basis for the microbial remediation of environmental oestrogens.

Hydrolytic Enzyme Production by Thermophilic Bacteria Isolated from Saudi Hot Springs.

Hydrolytic enzyme production by thermophilic bacteria isolated from hot springs in the southern region of Saudi Arabia was investigated. The physical and chemical properties of the hot springs prove to be an important environment for hydrolytic-enzyme-producing thermophilic bacteria. Eighty-four bacterial isolates were obtained from three hot springs: Al-Majardah, Al-Khubah and Al-Ardah. Screening of the isolates for enzyme production indicated that 78 isolates showed activity for one or more enzymes. Molecular identification and phylogenic analysis of selected promising isolates confirmed the identity of the isolates as Bacillus aerius, Bacillus licheniformis and Bacillus sonorensis, which have potential to produce the target enzymes α-amylase, protease and lipase, respectively. Optimization of hydrolytic enzyme production by bacterial strains was investigated using kitchen waste as a cheap carbon energy source. Maximum enzyme production was achieved after 72 hours of incubation at the beginning of the stationary phase of growth. Enzyme production was dependent on the initial pH value in the range of pH 7.5-8.5 and an optimal incubation temperature of between 55-60°C. Enzyme production increased gradually in proportion to the kitchen waste concentration; whereas maximum lipase production was gained at 5.0% (w/v) kitchen waste, 7.0% (w/v) of waste was optimal for both α-amylase and protease productivity. The results indicated that hot springs in Saudi Arabia are a substantial source of thermophilic bacteria producing industrially important enzymes using cheap and unexploited waste.

A wedge or a weight? Critically examining nuclear power’s viability as a low carbon energy source from an intergenerational perspective

Some integrated assessment studies of climate change have concluded that nuclear energy has a large potential impact on carbon abatement costs. However, these studies have often modeled the cost of nuclear waste management very simply or neglected it entirely. Common difficulties with existing studies include the use of simplistic nuclear waste management cost models and implicitly minimizing costs in the distant future by using discount rates that are arguably inappropriate for intergenerational cost-benefit analysis. These difficulties lead to results that may underestimate the cost of nuclear waste management – and therefore overestimate the value of nuclear energy as a low carbon energy technology. Here, we consider how a more realistic treatment of the nuclear waste disposal problem than has been used in previous studies could affect the viability of nuclear power in the context of integrated assessments of climate change. We construct a generic nuclear waste management cost model to develop cost estimates for nuclear waste management based on current policy, practice, and cost estimates for storage and disposal technologies. Our cost estimates are discounted using conventional constant exponential discounting as and a declining discount rate scheme. Results suggest that the optimism reflected in previous works is fragile: More realistic nuclear waste management cost models and uncertainty-appropriate intergenerational discount rates produce many more scenarios in which nuclear waste management costs are higher than previously assumed. As a consequence, nuclear energy’s economic attractiveness as a low carbon energy option is appears to be lower than earlier works suggested.

Techno-Economic Analysis of Rural 4th Generation Biomass District Heating

Biomass heating networks provide renewable heat using low carbon energy sources. They can be powerful tools for economy decarbonization. Heating networks can increase heating efficiency in districts and small size municipalities, using more efficient thermal generation technologies, with higher efficiencies and with more efficient emissions abatement technologies. This paper analyzes the application of a biomass fourth generation district heating, 4GDH (4th Generation Biomass District Heating), in a rural municipality. The heating network is designed to supply 77 residential buildings and eight public buildings, to replace the current individual diesel boilers and electrical heating systems. The development of the new fourth district heating generation implies the challenge of combining using low or very low temperatures in the distribution network pipes and delivery temperatures in existing facilities buildings. In this work biomass district heating designs based on third and fourth generation district heating network criteria are evaluated in terms of design conditions, operating ranges, effect of variable temperature operation, energy efficiency and investment and operating costs. The Internal Rate of Return of the different options ranges from 6.55% for a design based on the third generation network to 7.46% for a design based on the fourth generation network, with a 25 years investment horizon. The results and analyses of this work show the interest and challenges for the next low temperature DH generation for the rural area under analysis.

A Global Picture of Industrial Interdependencies Between Civil and Military Nuclear Infrastructures

Noting the increasingly unfavourable economic and operational position of nuclear power around the world, this paper reviews evidence for a hitherto neglected connection between international commitments to civil and military nuclear infrastructures. Reviewing well established understandings of interlinkages associated with fissile materials and other nuclear weapons related substances, the paper surveys a distinct – and currently potentially more important – kind of interdependency that has up to now received virtually no policy attention. This relates to the national industrial supply chains necessary for the manufacture and operation of nuclear propelled submarines, that are deemed central to strategic military doctrine in a few states – and to burgeoning ambitions in a number of others. One of the most striking features of these interdependencies, is that evidence is so strong in strategic military literatures, but that the issue is typically so neglected in energy policy analysis. So the repercussions extend beyond specific domains of civil and military nuclear policy making in themselves – significant as these may be. Across a range of countries, arguably the most important implications arise for the rigour and transparency of mainstream academic and energy policy analysis and the quality and accountability of wider democratic processes – that are failing to give due attention to the evident force of these connections. With civil nuclear power now increasingly recognised to be growing obsolescent as a low carbon energy source, but key military capabilities evidently depending so strongly on its maintenance, a potentially important new window of opportunity may be opening up for robust measures to reduce global military nuclear threats.