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The Association of Southeast Asian Nations (ASEAN) Member States are increasingly focusing on alternatives to electrolysis for the production of ‘green’ hydrogen, such as steam reforming of biofuels and biomass gasification. This chapter analyses the possibility of effectively achieving that under the existing general regulatory framework on energy production, namely the laws on the establishment and operation of factories, as well as environmental protection laws in ASEAN countries that regulate hydrogen production, with special attention on biomass gasification and steam reforming of biofuels. It finds that, despite falling outside of energy regulatory frameworks, hydrogen production from biomass/biofuels is regulated under general legal frameworks on manufacturing activities, occupational health and safety, as well as environmental protection laws. This is demonstrated in more detail by referring to a case study on Thailand. The chapter argues that, in the absence of robust criteria on hydrogen classification, it is possible for an electricity producer that generates electricity from grey hydrogen to gain financial benefits that were formerly thought to be reserved for the promotion of ‘green’ electricity production from blue or green hydrogen, in the case of re-electrification of hydrogen after storage.
We consider the direct numerical simulation of the flow over a forward-facing step protruding in a turbulent boundary layer. Proper orthogonal decomposition (POD) is applied to the velocity field in different regions using Fourier modes in the spanwise direction. The upstream flow is characterized by a structure with a spanwise modulation of the order of the step height, the origin of which is consistent with a centrifugal instability. The structure is associated with ejections over the step of low-speed fluid from the upstream recirculation, and organized into streaks through the action of strong spanwise motions along the step face. The spanwise-averaged instantaneous momentum deficit created by the ejections is directly related to the maximal shear rate at the edge of the step, and is well correlated with the dynamics of the downstream recirculation. The most energetic patterns consist of three-dimensional motions with a large spanwise wavelength located in the shear layer developing at the edge of the step, as well as two-dimensional fluctuations downstream of the reattachment. A linear model based on the interaction of the mean flow with the dominant POD modes is able to recover the main frequencies of the fluctuations at these wavenumbers. Including the time variations of the ejections into the model yields temporal spectra that resemble qualitatively those computed from the simulation. The results suggest that the global dynamics of the flow are at least partly driven by linear mechanisms and depend on the characteristic structure identified in the upstream region close to the step.
This chapter investigates the production of renewable hydrogen by electrolysis, namely the permits that are required to put an electrolyser on the ground. This will be investigated with the help of a case study on Finland. In Finland, permitting practices for renewable hydrogen electrolysers are only just starting to develop. Permitting procedures are still fragmented and there is no so-called one-stop-shop for hydrogen electrolyser permits. Several different permits by different authorities, both municipal and state authorities, are required and the permit procedures are usually independent of each other. These complicated permit procedures can be a challenge for setting up new hydrogen electrolysers as the pitfalls and challenges of the permit process, namely complicated bureaucracy as well as long permit handling times, can deter hydrogen investors. The chapter describes possible solutions to this problem and also sketches the actions taken by the government to tackle it. The conclusion is that a number of improvements to the system are currently being implemented, but their actual effects are yet to be seen and challenges still exist.
This chapter examines the role of the state in collaborative governance as well as the mix between hard (regulation) and soft modes of governance (orchestration) to achieve decarbonization in Sweden after the adoption of the 2017 Climate Policy Framework. The chapter focuses on state-led transformation and critically examines Sweden’s progress toward its overarching goal to become the first fossil-free welfare state by 2045. It investigates Sweden’s national strategies and governance modes to achieve decarbonization and overcome carbon lock-ins through institutional, economic, technological, and behavioral transformation. It concludes that Sweden’s path to decarbonization – like many other countries – resembles more of an incremental transition limited to certain sectors rather than the wholesale transformation toward achieving a fossil-free society.
Rotating convection is considered on the tilted $f$-plane where gravity and rotation are not aligned. For sufficiently large rotation rates, $\Omega$, the Taylor–Proudman effect results in the gyroscopic alignment of anisotropic columnar structures with the rotation axis giving rise to rapidly varying radial length scales that vanishes as $\Omega ^{-1/3}$ for $\Omega \rightarrow \infty$. Compounding this phenomenon is the existence of viscous (Ekman) layers adjacent to the impenetrable bounding surfaces that scale as $\Omega ^{-1/2}$. In this investigation, these constraints are relaxed upon utilising a non-orthogonal coordinate representation of the fluid equations where the upright coordinate aligns with rotation axis. This exposes the problem to asymptotic perturbation methods that permit: (i) relaxation of the constraints of gyroscopic alignment; (ii) the filtering of Ekman layers through the uncovering of parameterised velocity pumping boundary conditions; and (iii) the development of reduced quasi-geostrophic systems valid in the limit $\Omega \rightarrow \infty$. Linear stability investigations reveal excellent quantitative agreement between results from parameterised or unapproximated mechanical boundary conditions. For no-slip boundaries, it is demonstrated that the associated Ekman pumping alters convective onset through an enhanced destabilisation of large spatial scales. The range of unstable modes at a fixed thermal forcing is thus significantly extended with a direct dependence on $\Omega$. This holds true even for geophysical and astrophysical regimes characterised by extreme values of the non-dimensional Ekman number $E$. The nonlinear regime is explored via the global heat and momentum transport of single-mode solutions to the quasi-geostrophic systems which indicate $O(1)$ changes which do not scale with the size of $E$.
A cylindrical liquid thread readily destabilizes into a series of drops due to capillary instability, which is also responsible for undesirable bead-on-fibre structures observed when coating a thin fibre. In this experimental study, we show how a falling liquid thread can be stabilized by internally distorting the cross-sectional shape using two vertically hung fibres. Below a critical flow rate $Q_c$, the dual-fibre system deforms the falling thread into a smooth column with a non-circular cross-section, thereby suppressing instability. Above $Q_{{c}}$, the cylindrical thread is left undeformed by the fibres and destabilizes into beads connected by a stable, non-cylindrical film. An empirical stability threshold is identified showing that flow delays the onset of capillary instability when compared with a marginally stable quasi-static coating. When the flow is unstable $Q>Q_c$, the bead velocity $v$ obeys a simple scaling law that is well supported by our experiments over a large parameter range. This suppression technique can be extended to other slender geometries, such as a ribbon, which shows similar qualitative results but exhibits a different stability threshold due to spontaneous dewetting about its short edge.
This chapter examines the regulation of the hydrogen refuelling infrastructure in the European Union (EU). Since the EU is committed to reducing its carbon footprint and transitioning to sustainable energy sources, it sees hydrogen as an alternative to fossil fuels in the transport sector. This view reflects the tenor of the EU Green Deal, the Hydrogen Strategy, and the Sustainable and Smart Mobility Strategy. The success of these strategies depends on the successful resolution of several issues that would otherwise disrupt the just transition in the transport sector. The deployment of hydrogen refuelling stations requires a careful analysis of the various legal barriers that affect the value chain of the hydrogen industry.
This chapter discusses the permitting regime for electrolysers in Aotearoa New Zealand. Because green hydrogen is typically converted from water via electrolysis, hydrogen projects are dependent upon electrolysers – and, therefore, upon obtaining the necessary consents to build and operate these. However, New Zealand’s resource consent rules do not specifically provide for permitting electrolysers. Instead, resource management legislation provides for consent to be obtained for use of those resources that will be needed for (and impacted by) the electrolyser operation, with health and safety rules and industry standards prescribing the specifications for electrolysers and the way these can be used. The chapter asks what permits will be needed and what processes must be followed in order for an electrolytic hydrogen project to receive resource consent. While examining the consenting process, the chapter also considers whether New Zealand’s existing regulations can support its hydrogen aspirations.
We present the results of an experimental study of buoyancy-driven exchange flows in a vertical pipe, where the lower fluid is Newtonian of low viscosity and the upper fluid has a yield stress. The fluids are initially separated by a gate valve, opened at time $\hat {t}=0$. The fluids are miscible, but away from the diffusive limit. For a sufficiently large ratio $Y$, of the yield stress to the buoyancy stress, no sustained fluid motions arise: the flow is stable. For smaller $Y$ numbers an exchange flow results. Commonly, the less dense fluid penetrates upwards in a central finger, displacing the upper fluid downwards around the walls of the pipe. Three regimes are classified: helical finger, disconnected finger and slug flow. The transition between regimes is governed by increasing relevance of inertial to viscous stresses, in balancing buoyancy. The disconnected finger and slug flow regimes are associated with yielded fluid at the interface and early growth of instabilities. Helical fingers are viscous dominated and evolve slowly until late in the experiments. The scenarios studied represent an idealised set-up for the industrial process of plug cementing. The regimes identified are helpful for industrial process design.
As underlined by the EU`s Hydrogen Strategy for a Climate Neutral Europe and the REPowerEU programme, the development of a hydrogen economy is considered of strategic importance for the achievement of the EU Climate goals by both the EU and several of its Member States. As for any socio-technical transition, the development of the hydrogen economy requires careful policy and regulatory drafting, as well as the concrete implementation of projects affecting the living environment of people. Public participation is mandated under international, European and national law to ensure that the hydrogen economy best fits within the environmental and societal needs of the interested regions. This chapter uses the first fully fledged hydrogen valley in Europe as a case study to map the participatory requirements that should be applied in the development of a hydrogen economy and to show how these requirements have not been (fully) respected so far. In doing so, the chapter will provide data for comparative purposes and for the further development of the conceptual and applied frameworks for the hydrogen economy.
The Oceania region, particularly Australia and New Zealand, has recently welcomed a suite of strategies and policies to support the development of hydrogen. Australia’s current National Hydrogen Strategy strives to position the country as a top three global exporter of hydrogen by 2030. New Zealand’s Interim Hydrogen Roadmap aims to utilise hydrogen to decrease domestic emissions, foster economic development, and enhance energy security while supporting its 100 per cent renewable electricity by 2030 target. To achieve these hydrogen strategies and targets, it is essential to establish enabling regulatory frameworks. Regulation is required to strategically plan, identify, assess, and permit the development of onshore hydrogen production facilities and associated infrastructure, ensuring coexistence with multiple and diverse land uses. The chapter investigates the strategies, policies, and developing planning and licensing regulatory regimes for the development of renewable hydrogen in Australia and New Zealand. Specifically, it examines recent regulatory developments in two Australian states, Western Australia, and South Australia. Regulatory developments in both states are designed to facilitate the assessment and award of hydrogen production licences on Crown-owned pastoral leasehold land. As interest increases in the assessment and structure of hydrogen production licensing on complex land uses, the experiences in Australia and New Zealand provide important legal case studies. These experiences highlight the diverse approaches to planning and permitting hydrogen on pastoral land uses and offer valuable insights to support the development of future hydrogen economies.
This chapter provides an overview of the aims and research questions guiding this book. It introduces key terms and concepts and outlines the main contributions of the book. The chapter explains why the complex relations between state and non-state actors are crucial to understanding the implementation of the Paris Agreement. It provides a background to understanding the role of collaborative climate governance in the post-Paris governance landscape by highlighting the international context and describing Sweden’s climate policy framework. Finally, it provides a brief overview of each chapter in the book.
Normative ethics is divided between ethical theory and practical ethics. Three families of ethical theories are consequentialism, virtue ethics, and Kantianism. Consequentialism is the view that consequences determine what we ought to do. Virtue ethics is the view that right actions should be understood in terms of virtuous agents and their character. Kantianism’s central concern is with how rational agents ought to relate to themselves and to each other. Ethical theory is difficult to disentangle from practical ethics, which is concerned with what we ought to do in particular situations, which – along with the question “How should I live?” – is the most important topic in ethics and perhaps all of philosophy.