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Whereas hydrogen infrastructure is expected to develop as national infrastructure, the role of regional and local authorities in the creation and development of a hydrogen economy should not be underestimated for three reasons. First, they can bring parties together and position the specific region as hydrogen hotspot. Second, they can create local demand through the public procurement of public transport services and/or maintenance vehicles, also in areas where there is no industrial demand for hydrogen (yet). Third, local and regional authorities can also play a role in system integration. This chapter investigates the role of regional and local authorities in creating and developing a hydrogen market and the limits thereof, using a comparative approach between two ‘hydrogen regions’, Groningen and Puglia (Apulia). Although Puglia adopted a formal legal instrument and Groningen rather depends on policy instruments, both regions have similar policy objectives and means, and both regions struggle with a lack of national legislation on hydrogen.
Ultrasonic standing wave technology offers an ideal platform for manipulating particles in microfluidics. We study how fluid viscoelasticity and acoustic boundary formation in micro-confinements affect ultrasound-induced perturbations. These perturbations influence acoustic energy density (AED) and consequently particle transport dynamics. Our approach combines theoretical, numerical and experimental methods. Using the Oldroyd-B model for viscoelastic fluids, we advance acoustic radiation force (ARF) formulations of Doinikov et al. (Phys. Rev. E, vol. 104, no. 6, 2021a; Phys. Rev. E, vol. 104, no. 6, 2021b) for particles much smaller than the acoustic wavelength. This improved approach allows us to decouple AED and acoustic contrast factor terms in the ARF expression. It also enables us to examine the effects of viscoelastic parameters: $\mu ^*$ (ratio of the viscosity of the viscoelastic fluid to that of base Newtonian fluid) and $De$ (product of fluid relaxation time and actuation frequency) on AED and particle migration. Remarkably, we show that increasing fluid elasticity or $De$ transitions viscoelastic fluids from the energy dissipation (relaxation) mode to the energy storage (frozen) mode, increasing AED. Conversely, increasing viscosity ($\mu ^*$) reduces AED. Thus, our findings suggest that elastic effects accelerate particle migration, while viscous effects decelerate it. Consequently, a viscoelastic fluid-filled micro-confinement acts as an energy dissipation device at low $De$ and an energy storage device at high $De$. Particle migration can be controlled by adjusting viscoelastic and acoustic parameters, at a fixed power input. Our theoretical and numerical findings are validated with our experimental data. Our study advances the fundamental understanding of particle migration in viscoelastic fluids under ultrasound, and can significantly impact future studies on particle/cell migration in bio-fluids.
This chapter advanced the analytical framework of the book, which revolves around the role of the state in governing large-scale decarbonization through collaborative climate governance with interactions of non-state and sub-state actors, networks and multi-stakeholder partnerships in the various governance relations. We provide a coherent framework rooted in theoretical and conceptual debates on the multitude of relations between the state and non-state actors in the governance of climate change. By connecting these governance relations to three evaluative themes of the politics of decarbonization (justice, effectiveness, and legitimacy), we theorize how the state shapes decarbonization processes in a landscape of non-state and sub-state climate action. The chapter situates the book’s contributions to the wider scholarship and highlights the theoretical debates that the empirical chapters will revisit.
While energy production (the energy sector) has undergone huge efforts to reduce greenhouse gas emissions, transportation and heating are next to be tackle. Hydrogen could be a solution for one of them, the heating sector. This chapter focuses on the Netherlands as a case study to investigate the (absent) legal framework and the regulatory challenges that the development and deployment of hydrogen in the heating markets face. After an overview of the EU regulatory framework, it delves into the specificities of Dutch legislation. The Netherlands is a suitable object of study because it has instituted concrete initiatives from which the energy supervisor, the Authority for Consumers and Markets (ACM), has created a temporary framework. The analysis reveals significant gaps and inconsistencies in the regulatory landscape and offers concrete suggestions for sector-specific regulation. In addition, the chapter discusses the implications of the regulatory framework for market participants and their behaviour, as well as the role of competition law and potential sector-specific rules in ensuring a level playing field for all market actors. The Dutch experience could potentially generate a model that other EU Member States could follow.
This chapter returns to some central questions about value and valuing, including questions of intrinsic value and the distinction between values and preferences. It argues for value pluralism and discusses specifically prudential values, cultural values, aesthetic values, and natural values. Prudential values are those that relate to an agent’s own interests; cultural values are those that take artifacts or expressions as their objects; aesthetic values include beauty, but also other features such as the sublime; natural values are those that arise from nature’s autonomy. These and other values can conflict. Resources are available for resolving or reducing some value conflicts, but others are at least in practice unresolvable.
The chapter provides an introduction to the book and outlines the key aspects of the interplay between hydrogen and the law. After detailing the relevant technical aspects of hydrogen it engages with the existing literature on hydrogen and the law and situates this handbook in the wider debate. The literature review is clustered along the hydrogen value chain from production, via transmission and distribution to end use. The chapter concludes by highlighting the important role of clear regulatory frameworks for the hydrogen transition.
This chapter analyzes the regional and sectoral differences in how cities and municipalities engage in climate change networks. Over the past 20 years, an increasing number of cities, regions, companies, investors, and other non-state and subnational actors have voluntarily committed to reducing their GHG emissions. Such actions could help reduce the implementation gap. Along with the increase in commitments and the growing number of venues through which non-state actors can cooperate in order to govern climate change, it is necessary to track and evaluate such efforts. This chapter assesses the voluntary commitments made by Swedish municipalities, regions and multistakeholder partnerships to decarbonize by reducing GHG emissions. It finds large differences in which cities and municipalities that engage in networks. Large and urban municipalities in the south and along the eastern coast are well represented, whereas more rural municipalities along the Norwegian border are less represented in the data. The findings are discussed in terms of climate justice, highlighting the importance of having everyone onboard to create acceptance and reduce inequality in the transformation toward decarbonization.
Moral philosophy can be divided into two major fields: metaethics, which concerns the meaning and status of moral language, and normative ethics, which centers on what we ought to do. An ancient controversy in metaethics is that between moral realism, the view that moral language states facts about the world, and moral subjectivism, the view that moral language expresses the attitudes of speakers. Moral language seems to have both the characteristics of fact-stating discourse as well as some of the characteristics of expressions of attitudes. The challenge of metaethics is to reconcile the object-relatedness of realism with the motivational insight of subjectivism. Such a view must hold that valuing is contextual, object-directed, and constrained by biology, psychology, and history. Such a view is demonstrated through an investigation of the concept of intrinsic value.
How we should treat nonhuman animals is one of the most important environmental questions that we face. Although most people think of humans as having a qualitatively different moral status than nonhuman animals, there is no morally significant criterion for membership in the moral community that is satisfied by all and only humans. If the criterion is demanding enough (e.g., language), it excludes some humans; if it is permissive enough to include all humans (e.g., sentience), it includes some nonhumans. The discovery that “speciesism” is indefensible opens the door to a range of strong animal-protection philosophies – for example, Peter Singer’s “animal liberation,” which is founded on utilitarianism, and Christine Korsgaard’s “fellow creatures” view, which has a Kantian foundation. These views converge in concluding that many of the ways that we treat animals are wrong.
This chapter examines whether the legal and regulatory framework in France for the transport of energy is fit for hydrogen purposes and designed to accommodate that new energy carrier. Specifically, the aim of the analysis is to determine whether the French regulator chose the rules- or goal-setting approach when setting the framework for the transport of hydrogen. From early on, France attributed a prominent role to hydrogen for achieving its energy and climate goals and the decarbonization of its energy system, particularly transport and industry. This is demonstrated by the plethora of pilot power-to-gas projects across continental France, pushing the limits and exploring different synergies between hydrogen, gas and renewable energy sources. French gas infrastructure operators have already carried out extensive work to explore possibilities for integrating a significant amount of hydrogen into the gas mix by 2050, with limited infrastructure adaptation costs, deploying coordinated use of solutions including blending, methanation and even the option of 100 per cent hydrogen. Until recently, the legal and regulatory framework was lagging behind, as essential provisions that could facilitate hydrogen in the French gas transport infrastructure were missing. This, however, changed recently with the adoption of a specific chapter in the French energy code that also includes provisions on the transport of renewable hydrogen in natural gas pipelines and autonomous transport networks. This chapter, based on the analysis of these recent developments, assesses the type of regulatory approach followed by France regarding transport of hydrogen regulation and why this approach changes based on the regulatory subject. The flexibility and adaptability that characterise France’s decision on the regulatory approach to be used each time could prove valuable in other jurisdictions and could, despite some shortcomings, serve as a key tool for the design of reasonable legal frameworks for hydrogen transportation.
This work investigates the spatio-temporal evolution of coherent structures in the wake of a generic high-speed train, based on a three-dimensional database from large eddy simulation. Spectral proper orthogonal decomposition (SPOD) is used to extract energy spectra and energy ranked empirical modes for both symmetric and antisymmetric components of the fluctuating flow field. The spectrum of the symmetric component shows overall higher energy and more pronounced low-rank behaviour compared with the antisymmetric one. The most dominant symmetric mode features periodic vortex shedding in the near wake, and wave-like structures with constant streamwise wavenumber in the far wake. The mode bispectrum further reveals the dominant role of self-interaction of the symmetric component, leading to first harmonic and subharmonic triads of the fundamental frequency, with remarkable deformation of the mean field. Then, the stability of the three-dimensional wake flow is analysed based on two-dimensional local linear stability analysis combined with a non-parallelism approximation approach. Temporal stability analysis is first performed for both the near-wake and the far-wake regions, showing a more unstable condition in the near-wake region. The absolute frequency of the near-wake eigenmode is determined based on spatio-temporal analysis, then tracked along the streamwise direction to find out the global mode growth rate and frequency, which indicate a marginally stable global mode oscillating at a frequency very close to the most dominant SPOD mode. The global mode wavemaker is then located, and the structural sensitivity is calculated based on the direct and adjoint modes derived from a local spatial analysis, with the maximum value localized within the recirculation region close to the train tail. Finally, the global mode shape is computed by tracking the most spatially unstable eigenmode in the far wake, and the alignment with the SPOD mode is computed as a function of streamwise location. By combining data-driven and theoretical approaches, the mechanisms of coherent structures in complex wake flows are well identified and isolated.
This work presents models for the behaviour of both upstream- and downstream-travelling waves in screeching elliptical jets. Proper orthogonal decomposition is performed on experimental velocity data in both the major and minor axis planes, for an aspect ratio $AR=2$ converging elliptical jet operating at nozzle pressure ratios of $2.6$ and $3.4$. From this decomposition, the radial and axial structure of the guided-jet mode (GJM) and the Kelvin–Helmholtz instability are educed. Linear-stability analysis (LSA) is performed using both the experimentally obtained mean flow, and one obtained using Reynolds-averaged Navier–Stokes (RANS) at matched conditions. It is shown that the wavenumber predicted by LSA for both waves are within the range of experimentally observed wavenumbers. Furthermore, the model accurately predicts the structure of these waves at multiple axial locations, using either the experimental or RANS mean flow. Most critically, it is demonstrated that the GJM is only predicted to be neutrally stable at the screech frequency for a relatively limited streamwise domain, the size and location of which is dependent on the nozzle pressure ratio. A comparison with the amplitude envelope for the GJM extracted from the experimental measurements indicates that the maximum fluctuations associated with the GJM are collocated with this region of the flow that is predicted to support the GJM. While there have been extensive discussions about the frequency dependence of the GJM, this is the first demonstration that its existence is highly dependent on streamwise position within the flow.