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The assessment of greenhouse gases (GHGs) and air pollutants emitted to and removed from the atmosphere ranks high on international political and scientific agendas. Growing international concern and cooperation regarding the climate change problem have increased the need to consider the uncertainty in inventories of GHG emissions. The approaches to address uncertainty discussed in this special issue reflect attempts to improve national inventories, not only for their own sake but also from a wider, system analytic perspective. They seek to strengthen the usefulness of national emission inventories under a compliance and/or global monitoring and reporting framework. The papers in this special issue demonstrate the benefits of including inventory uncertainty in policy analyses. The issues raised by the authors and featured in their papers, along with the role that uncertainty analysis plays in many of their arguments, highlight the challenges and the importance of dealing with uncertainty. While the Intergovernmental Panel on Climate Change (IPCC) clearly stresses the value of conducting uncertainty analyses and offers guidance on executing them, the arguments made here in favor of performing these studies go well beyond any suggestions made by the IPCC to date. Improving and conducting uncertainty analyses are needed to develop a clear understanding and informed policy. Uncertainty matters and is key to many issues related to inventorying and reducing emissions. Considering uncertainty helps to avoid situations that can create a false sense of certainty or lead to invalid views of subsystems. Dealing proactively with uncertainty allows for the generation of useful knowledge that the international community should have to hand while strengthening the 2015 Paris Agreement, which had been agreed at the 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC). However, considering uncertainty does not come free. Proper treatment of uncertainty is demanding because it forces us to take the step from “simple to complex” and to grasp a holistic system view. Only, thereafter, can we consider potential simplifications. That is, comprehensive treatment of uncertainty does not necessarily offer quick or easy solutions for policymakers. This special issue brings together 13 papers that resulted from the 2015 (4th) International Workshop on Uncertainty in Atmospheric Emissions, in Cracow, Poland. While they deal with many different aspects of the uncertainty in emission estimates, they are guided by the same principal question: “What GHGs shall be verified at what spatio-temporal scale to support conducive legislation at local and national scales, while ensuring effective governance at the global scale?” This question is at the heart of mitigation and adaptation. It requires an understanding of the entire system of GHG sources and sinks, their spatial characteristics and the temporal scales at which they react and interact, the uncertainty (accuracy and/or precision) with which fluxes can be measured, and last but not least, the consequences that follow from all of the aforementioned aspects, for policy actors to frame compliance and/or global monitoring and reporting agreements. This bigger system context serves as a reference for the papers in the special issue, irrespective of their spatio-temporal focus, and is used as a guide for the reader.

It is important for a modern consumer of thermal energy to know and be able to reduce the consumption of thermal energy, for which purpose an energy audit should be conducted. Today, three types of energy audit of residential buildings are used in Ukraine. The first one is development of the energy performance certificate of the building. The obtained energy performance certificate will give an idea of the level of thermal losses of the building and identify the main areas where measures to reduce the consumption of energy resources should be taken. The second method involves carrying out experimental studies to determine the class of air permeability of enclosing structures, which also makes it possible to assess the level of heat losses of the building and the condition of the ventilation system of the building. The third type of energy audit involves carrying out thermal imaging of the building envelope for the subsequent analysis of infrared images. A methodological approach has been developed for processing multiple infrared images. An energy inspection of a residential house has been conducted on the basis of which an energy performance certificate was compiled. The premises of the residential building have been tested for air permeability. Considering the main types of energy audit, its advantages and disadvantages have been determined both for the consumer and for the employees who conduct the audit.  

Purpose. In modern conditions of energy consumption growth and a rapid increase in energy prices the actual problem is the development and implementation of energy efficiency programs and resource-saving conversion in to a source to provide the needs of industry and municipal power. The paper aims to solve the urgent problem of energy saving and efficient use of fuel-energy ones and heat supply system optimization on the basis of Uman National University of Horticulture (UNUH). Methodology. The work investigated the process of heating and hot water supply in the course of 2007-2015 years. Implementation of current problems of energy saving is grounded on the scientific-practical and efficient assurance of fuel and energy usage. At the same time energy-saving technologies are viewed as a priority direction of the energy sector development, reduction of man-induced impact on the environment and as a way of improving the competitiveness of the national economy. Findings. Statistical data acquisition and analyzing of gas flow and outside air temperature for nine years was carried out. On the basis of this analysis, the problem was identified and specific targets for its solutions were set. Originality. Scientific novelty lies in solving the problem of energy saving and efficient use of fuel resources in Ukraine through the use of a systematic approach, the methodology development of efficient use of different fuels and optimization of local heating operation, applying contemporary automation and control systems. Firstly it was in detail analyzed and conducted the comprehensive assessment of various factors influence on energy conservation. It takes into account the human factor, professionalism and responsibility of the operators of boilers and their superiors, as well as the relevant control services. Practical value. For UNUH campus hybrid use of solid fuel and gas boilers was carried out. Decentralization of the university heating system has been conducted through the restoration of 350 individual heating systems in residential buildings, remote departments and campus dormitories. The conclusions propose the list of activities upon the real economy of fuel and energy resources, and measures to overcome the economic and political crisis in the country.

The dynamic process of movement of vehicles in cities is associated with interaction with objects of the road environment. Road conditions, traffic and pedestrians require certain actions from the driver to ensure road safe-ty. Under such circumstances, the reliability and safety of road traffic in human-machine systems mainly depends on the functional state of the driver (provided that the technical component, the subsystem is “car”) and his ability to respond to changes in the traffic situation when obstacles arise (conflict situations). The development of states of tension and fatigue of the driver is associated with an increase in energy costs, which leads to a natural in-crease in the heart rate, respiration and other parameters indicating changes in the energy balance of the driver's body. Eye Tracking technology has been applied to detect attention. Energy costs were determined using a method that takes into account the frequency of the driver's external respiration when driving on the road and in the background. As a result, a model of change in the attention of drivers with driving experience and a model of en-ergy consumption when driving in the evening twilight at a certain level of illumination were obtained. To determine the influence of conflict situations during movement in the evening twilight on the indicator of attention and energy consumption of the driver, a study was carried out in real conditions on city streets. A group of drivers with experience of 3-5 years and 10-16 years performed arrivals in the evening twilight on passenger cars "C" class. Experimental studies of the indicator of drivers' attention and functional state in conditions of evening twilight were carried out on different categories of city streets. The study involved drivers between the ages of 20 and 40. The obtained dependences of the change in the driver's functional state on illumination showed that at low illumination levels in the evening twilight, a rapid increase in the driver's functional state shifts. Thus, the energy consumption of the driver while driving depends on the types of conflict situations and the level of illumination. It was found that for drivers with less than 5 years of driving experience, shifts in functional state were more im-portant than other drivers. Also, such drivers had lower attention indicators compared to experienced drivers with more than 10 years of driving experience. It was found that when the illumination changes at dusk, the energy consumption increases on average to 3.3 kcal / min for drivers with less than 5 years of experience, and for drivers with more than 10 years of experience, it increases by 2.4 kcal / min on average. Keywords: driver, conflict situations, attention, energy costs.

AbstractThe stability of synchronised networked systems is a multi-faceted challenge for many natural and technological fields, from cardiac and neuronal tissue pacemakers to power grids. For these, the ongoing transition to distributed renewable energy sources leads to a proliferation of dynamical actors. The desynchronisation of a few or even one of those would likely result in a substantial blackout. Thus the dynamical stability of the synchronous state has become a leading topic in power grid research. Here we uncover that, when taking into account physical losses in the network, the back-reaction of the network induces new exotic solitary states in the individual actors and the stability characteristics of the synchronous state are dramatically altered. These effects will have to be explicitly taken into account in the design of future power grids. We expect the results presented here to transfer to other systems of coupled heterogeneous Newtonian oscillators.

Using the method of computer modelling, considered in this paper is optimization of a passive air system design for cooling the powerful LED luminaire based on heat pipes and cooling rings. Thermal and mass characteristics of the cooling system have been studied for various design parameters: distance between rings, thickness of ring materials and thermal loads. It has been shown that, to provide a minimal case temperature of LED source, the optimal distance between cooling rings should be 6 mm, but in this case the mass of cooling system is not least. To reduce the luminaire mass, it is reasonable to choose the distance between the cooling rings equal to 8 mm. Then the temperature of light source increases by only 1.8 °С, or by 2.2%, while the mass of cooling system reduces by 1357 g, or by 20.5%. At the same time, lowering the ring thickness from 2 down to 0.8 mm can in addition reduce this mass by 2700 g, or by 48.6%. However, when doing so the temperature of LED source case is increased by 5.9 °С. The offered cooling system based on heat pipes is capable to provide the thermal resistance 0.131 С/W when scattering the thermal power 500 W under the maximum temperature of LED source crystal 135.5 С. Recommendations for application of the developed cooling system have been formulated.

The paper represents the analysis, which has helped to establish the usage of gas hydrate technologies in the methane conversion. This gas could be obtained in different ways. Possibilities and sources for the gas obtaining have been demonstrated. Use of other environmentally friendly sources to support operation in such systems in terms of joint energy complex has been considered. The necessary kinetic connections to provide operational sustainability of all the constituents have been given. The approach helps evaluate quantitatively the priority of its physicochemical transformations to obtain gas hydrates artificially. It is possible to transport methane at considerable distances when it is solidified. Actually, in this case there is no necessity to build costly compressor stations and pipelines for its transportation to consumers. The approach is extremely important for mining regions as it helps prolong the operating period and working out of the abandoned and off-balance coal reserves. In this case, it is proposed to apply special gasification technologies tending to maximum methane recovery. The proposed solutions give the possibility to define the trends of our further research. They will be highlighted in the following authors’ studies.

The possibility of band gap engineering (BGE) in RAlO3 (R = Y, La, Gd, Yb, Lu) perovskites in the context of trap depths of intrinsic point defects was investigated comprehensively using experimental and theoretical approaches. The optical band gap of the materials, E g, was determined via both the absorption measurements in the VUV spectral range and the spectra of recombination luminescence excitation by synchrotron radiation. The experimentally observed effect of E g reduction from ∼8.5 to ∼5.5 eV in RAlO3 perovskites with increasing R3+ ionic radius was confirmed by the DFT electronic structure calculations performed for RMIIIO3 crystals (R = Lu, Y, La; MIII = Al, Ga, In). The possibility of BGE was also proved by the analysis of thermally stimulated luminescence (TSL) measured above room temperature for the far-red emitting (Y/Gd/La)AlO3:Mn4+ phosphors, which confirmed decreasing of the trap depths in the cation sequence Y → Gd → La. Calculations of the trap depths performed within the super cell approach for a number of intrinsic point defects and their complexes allowed recognizing specific trapping centers that can be responsible for the observed TSL. In particular, the electron traps of 1.33 and 1.43 eV (in YAlO3) were considered to be formed by the energy level of oxygen vacancy (VO) with different arrangement of neighboring YAl and VY, while shallower electron traps of 0.9-1.0 eV were related to the energy level of YAl antisite complexes with neighboring VO or (VO + VY). The effect of the lowering of electron trap depths in RAlO3 was demonstrated for the VO-related level of the (YAl + VO + VY) complex defect for the particular case of La substituting Y.