Abstract

Renewable energy sources exploitation acquires special importance for creating low-carbon energy systems. In Mexico a national regulation limits the fossil fuel-based electricity generation to 65%, 60% and 50% by years 2024, 2030 and 2050 respectively. This study evaluates several scenarios of renewables incorporation into the Mexican electricity system to attend those targets as well as a 75% renewables-based electricity share target towards a 100% renewable system. By its size, the Mexican electricity system, with a generation of 260.4 TWh/year (85% based on fossil fuels), can be regarded as an illustrating reference. The impact of increasing amounts of wind, photovoltaic solar, biomass, biogas, geothermal, hydro and concentrating solar power on the system’s capacity to attend demand on a one-hour timescale resolution is investigated utilizing the EnergyPLAN model and the minimum total mix capacity method. Possible excess of electricity production is also assessed. For every target year, a solution is obtained corresponding to the combination resulting in the minimum total generation capacity for the electricity system. A transition strategy to a system with a high share of renewables-based electricity is designed where every transition step corresponds to the optimal energy mix for each of the target years.

Abstract

This paper analyses the cross-sectoral integration of the water-energy nexus in Brazil. Recent droughts resulted in unprecedented water scarcity. This caused water shortages for population and agriculture, as well as for electricity production (hydropower being the main source of electricity production). As a result, the system became more vulnerable to blackouts. To alleviate the problem, fossil fuels were used as a back up. Droughts, floods and other water-related problems will not dissipate as time goes by in Brazil. The dependency on one single predominant source (hydropower) makes Brazil’s electricity supply vulnerable. This study shows through data analysis, flow diagrams and metrics the interrelation between water and energy. Based on historical data, the analysis shows the importance of the water demand for hydropower, cooling for thermal plants, and the extraction and production of biofuels, as well as of the energy demand of water services (water supply, wastewater treatment).

Abstract

Demand Response can be seen as one effective way to harmonize demand and supply in order to achieve high self-coverage of energy consumption by means of renewable energy sources. This paper presents two different simulation-based concepts to integrate demand-response strategies into energy management systems in the customer domain of the Smart Grid. The first approach is a Model Predictive Control of the heating and cooling system of a low-energy office building. The second concept aims at industrial Demand Side Management by integrating energy use optimization into industrial automation systems. Both approaches are targeted at day-ahead planning. Furthermore, insights gained into the implications of the concepts onto the design of the model, simulation and optimization will be discussed. While both approaches share a similar architecture, different modelling and simulation approaches were required by the use cases.

Abstract

This paper presents a real industrial example in which the steam utility network of a refinery is modelled in order to evaluate potential Heat Integration retrofits proposed for the site. A refinery, typically, has flexibility to optimize the operating strategy for the steam system depending on the operation of the main processes. This paper presents a few examples of Heat Integration retrofit measures from a case study of a large oil refinery. In order to evaluate expected changes in fuel and electricity imports to the refinery after implementation of the proposed retrofits, a steam system model has been developed. The steam system model has been tested and validated with steady state data from three different operating scenarios and can be used to evaluate how changes to steam balances at different pressure levels would affect overall steam balances, generation of shaft power in turbines, and the consumption of fuel gas.

Abstract

To investigate the effect of organic and inorganic amendments on heavy metal immobilization in soil and organic carbon sequestration, a growth chamber study over a period of 18 months was conducted. Phytoremediation of two degraded soils, smelter-polluted soil and post-mining soil, was carried out using Scots Pine (Pinus Sylvestris L.) and Giant Miscanthus (Miscanthus x Giganteus). The increase in organic carbon content for lake chalk amended soils was noted. In addition, the largest root biomass production after fertilization of heavy metal contaminated soil with lake chalk was observed. This soil additive increases soil pH and reduces heavy metal mobility, which finally minimizes the harmful effect of metals on plant life and growth. Root biomass production of Giant Miscanthus was significantly higher than Scots pine root biomass for both soils. This may indicate better phytosequestration properties of Giant Miscanthus, especially in the case of land degradation due to mining and destruction of soil profiles.

Abstract

Public protests, which lead to increased administrative and permission procedures, are amongst the most important obstacles in development of wind energy projects. The community’s fears of visual and acoustic impacts of new power plants are commonly recognized as the weakest aspects of public acceptance. To address these issues Visualisation Dome has been designed to better communicate the economic, political, spatial, ecological and social benefits of wind power plants and the associated risks to local communities. The approach combines the experimental and simulation method. The integrated analysis software tool, which allows assessing the impacts of planed wind power plants underpins their 360-degree video and audio simulations. The Visualisation Dome demonstration resulted in 57% of the interviewed participants improving their opinion of wind power following the experience. Visualisation Dome’s novel approach for improving procedural justice of wind energy projects development forms innovative, interactive and streamlined processes, and enables constructive participation of audiences.

Abstract

Nowadays, the installation of efficient lighting sources and Information and Communications Technologies can provide economic benefits, energy efficiency, and visual comfort requirements. More advantages can be derived if the public lighting infrastructure integrates a smart grid. This study presents an experimental multifunctional infrastructure for public lighting, installed in Palermo. The system is able to provide smart lighting functions (hotspot Wi-Fi, video-surveillances, car and pedestrian access control, car parking monitoring and support for environmental monitoring). A remote control and monitoring platform called “Centro Servizi” processes the information coming from different installations as well as their status in real time, and sends commands to the devices (e.g. to control the luminous flux), each one provided with a machine to machine interface. Data can be reported either on the web or on a customised app. The study has shown the efficient operation of such new infrastructure and its capability to provide new functions and benefits to citizens, tourists, and public administration. Thus, this system represents a starting point for the implementation of many other lighting infrastructure features typical of a “smart city.”

Abstract

Compressed natural gas can be used in diesel engine with great benefits, but because of its low reactivity it is usually used in a so called dual fuel combustion process. Optimal parameters for dual fuel engines are not yet investigated thoroughly which is the motivation for this work. In this work, a numerical study performed in a cycle simulation tool (AVL Boost v2013) on the influence of different injection timings on fuel slip into exhaust and influence of compression ratio on knock phenomena in port injected dual fuel engine was conducted. The introduction of natural gas into the intake port of a diesel engine usually results in some fuel slipping into the exhaust port due to valve overlap. By analysing the simulation results, the injection strategy that significantly decreases the natural gas slip is defined. The knock occurrence study showed that the highest allowed compression ratio that will result in knock free operation of the presented engine is 18 for ambient intake condition, while for charged intake conditions the compression ratio should be lowered to 16.

Abstract

Transition to alternative energy systems is indicated by EU Commission as a suitable path to energy efficiency and energy saving in the next years. The aims are to decrease greenhouses gases emissions, relevance of fossil fuels in energy production and energy dependence on extra-EU countries. These goals can be achieved increasing renewable energy sources and/or efficiency on energy production processes. In this paper an innovative micro-cogeneration system for household application is presented: it covers heating, domestic hot water and electricity demands for a residential user. Solid oxide fuel cells, heat pump and Stirling engine are utilised as a system to achieve high energy conversion efficiency. A transition from traditional petrol cars to electric mobility is also considered and simulated here. Different types of fuel are considered to demonstrate the high versatility of the simulated cogeneration system by changing the pre-reformer of the fuel cell. Thermodynamic analysis is performed to prove high efficiency with the different fuels.

Abstract

Energy and water are the two major concerns which humanity is presently facing at large, and many concerns are being expressed at the international, national and local level related to these critical issues. Optimizing the use of energy and water in buildings are significant challenges faced by architects and designers in developing countries like India while planning of townships and designing of buildings and their surrounding environments. Different building regulations are formulated in various Indian cities to optimize the use of energy and water in built environment. But, these regulations are not efficiently enforced and followed. As a result, the problem related to insufficient supply and inappropriate use of energy and water persists, which leads to excessive pressure on already scarce energy and water resources. Environmentally sensitive in hill towns of India are facing most of the issues, where provision and improvement of infrastructural facilities is a tedious task and may lead to enormous impacts on the environment. In this paper, an attempt is made to understand their issues and problems of different building regulations related to energy and water enforced in Indian hill towns. Valuable lessons are outlined related to formulation and implementation of building relations imposed on development in hilly areas in other countries. This paper also includes various interventions required to incorporate regulations related to energy and water in existing building regulations of Indian hill towns.

Abstract

Abstract

This study is a survey conducted in questionnaire format on the usage time and the quantity of consumer durables that consume energy, relevant to households in Kobe, Japan. Based on the data containing quantity and daily usage days of consumer durables obtained from the questionnaire survey, the rate of energy consumption for each household type was calculated. By using results, energy consumption of household sector in Kobe in 2010 was estimated at approximately 25,559 TJ. Taking future changes in the number of households in Kobe into consideration, the future energy consumption in 2035 would decline by approximately 6.0% from 2010. We also revealed that full electrification of residential houses would change energy consumption structures rather than overall the energy consumption.

Abstract

The widespread adoption of electric vehicles and electric heat pumps would result in radically different household electrical demand characteristics, while also possibly posing a threat to the stability of the electrical grid. In this paper, a micro-trigeneration system (composed of a 6.0 kW_el cogeneration device feeding a 4.5 kW_cool electric air-cooled vapor compression water chiller) serving an Italian residential multi-family house was investigated by using the dynamic simulation software TRNSYS. The charging of an electric vehicle was considered by analyzing a set of seven electric vehicle charging profiles representing different scenarios. The simulations were performed in order to evaluate the capability of micro-cogeneration technology in: alleviating the impact on the electric infrastructure (a); saving primary energy (b); reducing the carbon dioxide equivalent emissions (c) and determining the operating costs in comparison to a conventional supply system based on separate energy production (d).

Abstract

Minimisation of variability of energy delivered from a group of wind plants into the power system using portfolio theory approach was studied. One of the assumptions of that theory is Gaussian distribution of the sample, which is not satisfied in case of wind generation. Therefore, optimisation of a “portfolio” of plants with different goal functions was studied. It was supposed that a decision on distribution of a fixed amount of generation capacity to be installed among a set of geographical locations with known wind statistics is to be made with minimised variability of generation as a goal. In that way the statistical cancellation of variability would be used in the best possible manner. This article is a brief report on results of such an investigation. An example of nine locations in Croatia was used. These locations’ wind statistics are known from historic generation data.

Abstract

Experimental data of total wind generation, recorded at 5 minute intervals and published by the Bonneville Power Administration for the years 2007 to 2013, were analyzed on a year by year basis. All data were normalized to total installed power of wind plants. Statistical distribution functions were obtained for the following wind generation-related quantities: total generation as percentage of total installed capacity; change in total generation power in 5, 10, 15, 20, 25, 30, 45, and 60 minutes as percentage of total installed capacity; duration of intervals with total generated power, expressed as percentage of total installed capacity, lower than certain pre-specified level. The statistical distributions obtained from the data were used to devise simple, yet accurate, theoretical models. The models presented here can be utilized in analyses related to power system economics/policy, because they describe availability of wind energy resource in simple statistical terms relevant to interactions of wind generation with electricity system, and electricity markets. After a brief display of the models, the article concentrates on static properties of the observed system’s electricity generation related to its capacity credit, as well as on dynamic properties related to the demand for fast regulation (i.e., secondary and fast tertiary reserve). Both properties are important for technical planning of future electricity systems, as well as rational design of policy measures.

Abstract

Water is a human right which is recognised globally, with an increasing focus being placed on the ethical considerations of water use. The paper focuses on investigating access and perceptions surrounding this basic need in the Bekkersdal community and the Wonderfonteinspruit, in the Gauteng Province, South Africa. It is hypothesised that several challenges exist both internally and externally in the process of ensuring the right to water in Bekkersdal, from both an environmental and service provision perspective. Through the use of a questionnaire conducted with a statistically representative group from the Bekkersdal community, the following issues were investigated: current water use of municipal and river water, challenges regarding water availability and quality, perceptions regarding the state of the Wonderfonteinspruit and future water use wants and needs. The results indicate a strong reliance on municipal water complicated with water service delivery issues, which resulted in 10% of the residents making use of the polluted Wonderfonteinspruit on a regular basis. Furthermore, the need for solutions to water supply and availability solutions should be developed in conjunction with community members. This research represents some of the first steps that need to be taken to do so.

Abstract

The objective of this research was to study how the maximum vehicle weight (76 t) will affect roundwood transportation in environmentally efficient transportation system. Actual traffic levels were assessed with calculations based on the vehicle configurations (60, 64, 68, and 76 t) a year after the weight limit was raised. Consequences of this change were also assessed for predicted future traffic levels. The reduction in operational vehicle-km was 12.5% (versus a decrease of 9.3% based on the legal weight), though this may underestimate the long-term prediction (26.7%) that will be achieved when the roundwood transportation sector adjusts fully to the higher maximum weight limit. The migration of loads to heavier vehicles did not create any wood harvesting problems for 60, 64 and 68 t vehicle configurations. However, 76 t vehicles were often volume-constrained, so it was harder to achieve the maximum weight. The main operational challenge was pulpwood (3.5 and 4.0 m) when onboard loaders were not available. Based on comparison of roundwood length measurements as an indicator of volume-constraint vehicles, the best practice system is discussed to enable an efficient transportation system for sustainable wood procurement.

Abstract

In the current paper, the sustainability of community-based water supply projects in four different states in Sudan was assessed using a set of multidimensional indicators. A sustainability index was developed using a set of sustainability criteria including technical, reliability/risk, social, organisational, financial as well as sustainability. Basic sustainability criteria were selected based on literature review and stakeholders discussion. For each criterion a set of observable indicators was identified, in total 23 indicators were identified. Furthermore, a detailed statistical analysis and model development was carried out to identify main sustainability determinants for community-based water supply projects in Sudan. Partial least squares-path modelling was used to determine and quantify relationships between the sustainability criteria. The results showed that although all analyzed projects were relatively young projects (1 to 4 years), all projects showed low sustainability performance. This was mainly due to organizational as well as financial aspects, which also was confirmed by path modeling analysis, the sustainability of community-based water supply projects was directly related to organizational aspects, but indirectly related to financial issues. There is a need to give more attention to the communities’ organizational and financial abilities and to leverage their ability through governmental and/or non-governmental organization support especially after project implementation phase.

Abstract

Since the majority of network concession contracts in Germany were set to expire some time between 2005 and 2016, a window of opportunity arose in which to rebuild and remunicipalise the local energy supply. As a result, 72 new local power companies were established in Germany within the space of just seven years (between early 2005 and late 2012). This paper provides an introduction to the topic of establishing municipal utilities in Germany. The findings were identified on the basis of the comprehensive screening of all newly established municipal utilities in Germany. Our analysis provides information about regional concentration, the size of municipalities, the legal forms of the newly founded municipal public utilities and the role of strategic partnerships. The key findings are that remunicipalisation is not a question of size and that knowledge gaps may be closed by entering into close strategic partnerships.

Abstract

Intrinsic catalytic properties of mineral matrices of various kinds (basalts, clays, sandstones) were studied, which are of interest for in-situ heavy oil upgrading (i.e., underground) to create advanced technologies for enhanced oil recovery. The elemental, surface and phase composition and matrix particle morphology, surface and acidic properties were studied using elemental analysis, X-ray diffraction, adsorption and desorption of nitrogen and ammonia. The data on the catalytic activity of inorganic matrices in ammonium nitrate decomposition (reaction with a large gassing), oxidation of hydrocarbons and carbon monoxide, and hydrocracking of asphaltenes into maltenes (the conversion of heavy hydrocarbons into more valuable light hydrocarbons) were discussed. In order to check their applicability for the asphaltenes hydrocracking catalytic systems development, basalt and clay matrices were used as supports for iron/basalt, nickel/basalt and iron/clay catalysts. The catalytic activity of the matrices in the reactions of the decomposition of ammonium nitrate, oxidation of hydrocarbons and carbon monoxide, and hydrocracking of asphaltens was observed for the first time.