• Energy Research
• mechanical engineering close
• 13. Climate action close
• 12. Responsible consumption close
• GB close

The global climate protection policy aimed at achieving a zero greenhouse gas emissions target has led to the fast incorporation of large-scale photovoltaics into the power network. The conventional AC grid was not modeled to be incorporated with large-scale non-synchronous inverter-based energy resources (IBR). Incorporating inertia-free IBR into the grid leads to technical issues such as the degradation of system strength and inertia, therefore affecting the safety and reliability of the electrical power system. This research introduced a new solution to incorporate a flywheel in the rotor of a synchronous machine to improve the dynamic inertia control during a system disruption and to maintain the constancy of the system. The objective of this work is to enhance large-scale photovoltaic systems in such a way that they can avoid failures during a fault. A model of transient constancy with two synchronous generators and a LSPV is established in PowerWorld modeling software. A line-to-ground and three-phase fault are simulated in a system with up to 50% IBR penetration. The outcomes showed that the power network was able to ride through faults (RTFs) and that the stability of frequency and voltage are enhanced because of a flywheel that improved grid inertia and strength.

Tidal turbine blades are subject to harsh loading and environmental conditions, including large thrust and torsional loadings, relative to wind turbine blades, due to the high density of seawater, among other factors. The complex combination of these loadings, as well as water ingress and associated composite laminate saturation, have significant implications for blade design, affecting overall device design, stability, scalability, energy production and cost-effectiveness. This study investigates the effect of seawater ingress on composite material properties, and the associated design and life expectancy of tidal turbine blades in operating conditions. The fatigue properties of dry and water-saturated glass fibre reinforced laminates are experimentally evaluated and incorporated into tidal blade design. The fatigue lives of pitch- and stall-regulated tidal turbine blades are found to be altered by seawater immersion. Water saturation is shown to reduce blade life about 3 years for stall-regulated blades and by about 1-2 years for pitch-regulated blades. The effect of water ingress can be compensated by increased laminate thickness. The tidal turbine blade design methodology presented here can be used for evaluation of blade life expectancy and tidal device energy production. (C) 2018 Elsevier Ltd. All rights reserved.

Abstract An overview is given of status of projects for the disposal of radioactive waste in very deep boreholes in crystalline rocks which demonstrates all main pros and cons of this technology. New opportunities offered by drilling long horizontal drillholes in ductile formations can provide the basis for projects that have the potential to overcome many of the disadvantages of deep boreholes. The concept of disposal in horizontal drillholes brings together the technologies of borehole and mined repositories using the advantages of both, and therefore deserves an expert discussion at international level.

This is the first attempt to combine disposed bottle caps and natural fibres into sandwich panels. A full factorial design is performed to identify the effects of the skin type (aluminium or coir fibre reinforced laminates) and bottle cap core packing (cubic and orthotropic) on the mechanical properties of the proposed panels. The coir fibre composite skin provides maximum core shear strength, 29 % higher than the aluminium-based panels, in cubic packing, while the flexural modulus is reduced by 45 %. An interlocking effect between the skin and the core is evidenced when coir fibre composites are used. In addition, the cubic cell packing increases the specific mechanical properties, even though with a higher density. The results highlight a promising association of green components and plastic bottle caps for secondary structural applications.

The Government run UK Renewable Heat Incentive (RHI) scheme allows cash back payments to be made to producers of renewable heat. As a world first for renewable heat, it aims to tackle head on the issues surrounding emissions, energy use, and climate change targets. However, whilst the scheme goes a long way towards meeting these climate change targets, issues have been identified that may compromise its effectiveness. This paper aims to examine the progress of the RHI since its launch in November 2011, and avenues towards a more effective deployment

Abstract The relationship between fuel consumption in a multi-storey block of flats and climatic exposure is investigated. Fuel consumption anomalies between identical flats are attributed to vagaries in the airflow around the building and highlight the need for improved standards of thermal insulation and/or differential thermal insulation, dependent upon flat location. Climate and building design and the subject of building Climatology in architectural education are discussed briefly.

Mass transport phenomenon was first recognized by Stokes in 1847 using a Lagrangian description. Later, a basic theory for the mass transport in water waves in viscous fluid and of finite depth was derived by Longuet-Higgins in 1953. Theoretical solutions of mass transport in progressive waves of permanent type are subjected to the definitions of wave celerity in deriving the various finite amplitude wave theories. As it has been generally acknowledged that the Stokes wave theory can not yield a correct prediction of mass transport in the shallow depths, some new theories have been developed. Recently the authors(1974 § 1977) have derived a new finite amplitude wave theory in shallow water for quasi- Stokes and cnoidal waves by the so-called reductive perturbation method, in which the mass transport is formulated both in Lagrangian and Eulerian descriptions. On the experimental verification, Russell and 0sorio(1957) investigated and compared Longuet-Higgins' solution with experimental data of Lagrangian mass transport velocity obtained in a normal closed wave tank of finite length. Since then, many investigations, and nearly all of them, have employed the finite length of wave tank in carrying out their experiments. However, no experiment has yet been attempted at verifying the Stokes drift in progressive waves of permanent type in a wave tank of infinite length. It is not realistic nor economical in constructing such an infinitely long flume to investigate experimentally the mass transport velocity in progressive waves. Instead of using such an ideal wave tank, a new one incorporated with natural water re-circulation was equipped to carry out experiments by the authors(1978). It was confirmed from these experiments that mass transport in progressive waves of permanent type exists in the Same direction of wave propagation throughout the depth, and agrees with both the Stokes drift and the authors' new formulations, within the test range of experiments.