Abstract

The performance of estimation algorithms is vital for the correct functioning of batteries in electric vehicles, as poor estimates will inevitably jeopardize the operations that rely on un-measurable quantities, such as State of Charge and State of Health. This paper compares the performance of three nonlinear estimation algorithms: the Extended Kalman Filter, the Unscented Kalman Filter and the Particle Filter, where a lithium-ion cell model is considered. The effectiveness of these algorithms is measured by their ability to produce accurate estimates against their computational complexity in terms of number of operations and execution time required. The trade-offs between estimators' performance and their computational complexity are analyzed.

Abstract

With the ratification of the Energy Community of Southeast Europe countries (14th July 2006) the Republic of Serbia, among other things, accepted the obligation to adopt and implement a plan of applying the Directive 2001/77/EC about promoting the production of electrical energy from renewable energy sources. The projects of the renewable energy resources use have a positive impact on the environment, in particular about the mitigation of global climate change and local environmental sustainability.

Abstract

For remote underdeveloped and sparsely populated regions, the use of national power grids to provide electricity can be both unsustainable and impractical. In recent years, decentralised renewable power has gained popularity, endowing social benefits to the local inhabitants through clean rural electrification. However, power reliability and system autonomy are often the primary technical concerns as current systems are largely single source reliant. Hybrid power systems that utilise multiple complementary renewables can help to reduce the dependency on conventional unclean options. A few selected case studies for both single source and hybrid power systems are reviewed, analysing critical success factors and evaluating existing difficulties. The additional integration of the novel rain-powered kinetic-to-electric generator technology to the existing hybrid model is analysed. As with development in general, there is no one-size-fits-all solution to bringing power to remote communities and the most sustainable solution should be found through analysing local resources, environmental conditions and maximising local involvement.

Abstract

In the last decades, the Brazilian government has put many public policies in place in order to create a favourable environment to promote energy efficiency and clean energy. In this paper we discuss the use of research and development financing support by the clean energy industry in Brazil. To do so, we carried out an empirical research analysing secondary data from legislation, literature case studies, and public and industry reports in order to determine if the companies of the clean energy industry have public financial support to research and development. Our ongoing research shows that, despite incentives to stimulate the dissemination of clean energy, the participation of some of the clean energy is very small (especially solar). We believe that the contributions of this study will assist policy makers, and the whole industry, to improve clean energy research and development investments in Brazil.

Abstract

The introduction of battery electric vehicles (BEVs) could help to reduce dependence on fossil fuels and emissions from transportation and as such increase energy security and foster sustainable use of energy resources. However a major barrier to the introduction of BEVs is their limited battery capacity and long charging durations. To address these issues of BEVs several solutions are proposed such as battery swapping and fast charging stations. However apart from these stationary modes of charging, recently a new mode of charging has been introduced which is called inductive charging. This allows charging of BEVs as they drive along roads without the need of plugs, using induction. But it is unclear, if and how such technology could be utilized best. In order to investigate the possible impact of the introduction of such inductive charging infrastructure, its potential and its optimal placement, a framework for simulating BEVs using a multi-agent transport simulation was used. This framework was extended by an inductive charging module and initial test runs were performed. In this paper we present the simulation results of these preliminary tests together with analysis which suggests that battery sizes of BEVs could be reduced even if inductive charging technology is implemented only at a small number of high traffic volume links. The paper also demonstrates that our model can effectively support policy and decision making for deploying inductive charging infrastructure.

Abstract

This paper investigates the impacts of Taipei Mass Rapid Transit (MRT) system on household car ownership and analyses how socioeconomic characteristics affect household car ownership. We employ a difference-in-difference (DID) strategy integrated with generalized Poisson regression models to examine the effects of MRT. The results are as follows: first, the establishment of Taipei MRT significantly reduced the level of household car ownership. Expanding the network of MRT system can be a feasible policy to control car ownership. Second, the levels of household car ownership are related to household’s socioeconomic characteristics. Third, households with high dependence on public transport own fewer cars after Taipei MRT began operation. Hence, the traffic authority should adopt more effective methods to encourage public transit use in order to decrease household car ownership.

Abstract

In this paper we built three types of artificial neural networks, namely: Feed forward networks, Elman networks and Cascade forward networks, for forecasting wind speeds and directions. A similar network topology was used for all the forecast horizons, regardless of the model type. All the models were then trained with real data of collected wind speeds and directions over a period of two years in the municipal of Puumala, Finland. Up to 70th percentile of the data was used for training, validation and testing, while 71–85th percentile was presented to the trained models for validation. The model outputs were then compared to the last 15% of the original data, by measuring the statistical errors between them. The feed forward networks returned the lowest errors for wind speeds. Cascade forward networks gave the lowest errors for wind directions; Elman networks returned the lowest errors when used for short term forecasting.

Abstract

In the past, industrialized countries have invested in or financed numerous renewable energy projects in developing countries, primarily through the Clean Development Mechanism (CDM) of the Kyoto Protocol. However, critics have pointed to its bureaucratic structure, problems with additionality and distorted credit prices as ill-equipped to streamline renewable energy investment. In this paper, we simulate the impact of policy on investment decisions on whether or not to invest in wind energy infrastructure in India, Brazil and China. Data from 2,578 past projects as well as literature on investor behaviour is used to inform the model structure and parameters. Our results show that the CDM acts differently in each country and reveal that while streamlining the approval process and reconsidering additionality can lead to non-trivial increase in total investment, stabilizing policy and decreasing investment risk will do the most to spur investment.

Abstract

Transition to a green economy is one of key directions of Russian modernisation. According to the “eastern vector” of the Russian economy, principles of a green development are crucial for regions of Eastern Siberia, one of which is the Baikal area. Actual directions of economic activities are a mining industry on a base of polymetallic ore fields, and a touristic industry in a frame of Special Economic Zone “Baikal haven”. Economic growth is a necessary condition for improvement of living standards of the local population, but environmental and economic indicators of these development directions differ considerably. Transition from traditional economic indicators, oriented on consumption, to effective development, focused on preserving of ecological services of natural landscapes, is one of the most important issues of green economy in a practice. This article considers perspective directions of economic development within the Republic of Buryatia as a part of the Baikal Natural Area, and evaluates possibilities of transition to a green economy.

Abstract

The underlying assumption of this study is that in order to retain the competitiveness while reaching for the EU targets regarding low-energy construction, district heating companies need to develop new business and service models. How district heating companies could broaden their perspective and switch to a more service-oriented way of thinking is a key interest of our research. The used methods in our study are house builder interviews and a questionnaire. With the help of these methods we discussed the potential interest in heating related services acquiring a comprehensive understanding of the customer needs. The results indicate the importance of certain criteria when choosing the heating system in households: easiness, comfort and affordability seem to dominate the house builders’ preferences. Also environmental awareness seems to be for many an important factor when making a decision about the heating of the house. Altogether, based on the results of this study, we suggest that the prospects of district heating could benefit from highlighting certain aspects and strengths in the future. District heating companies need to increase flexibility, readiness to adopt new services, to invest in new marketing strategies and improving the communication skills.

Abstract

Investigations of energy efficiency of 25 pumps showed wire-to-water efficiencies ranging from 30% to 60%, with an average of 47%. Raising the efficiency of just 7 pumps to the realistic target of 60% would require an initial investment of 126 k€ and represent a net present value (profit) of 446 k€ over a 10-year pump lifetime, saving 8.6 kt of CO2 emissions. The primary measures for raising efficiency are in order of priority: 1) improving pre-filtration of raw water to prevent rapid mechanical wear due to suspended particles during monsoon, 2) providing training, improved working conditions, and better tools and spare parts among pump operators and 3) replacing aging, oversized pumps with properly sized pumps operating close to peak efficiency. As of January 2014 the results have been confirmed by a Bureau of Energy Efficiency-certified energy auditor and the extent and funding of efficiency measures implementation is in planning.

Abstract

When facing the challenge of restructuring the energy system, bottom-up initiatives can aid the diffusion of decentralized and clean energy technologies. We focused here on a bottom-up initiative of citizen-funded and citizen-operated photovoltaic power plants. The project follows a case study-based approach and examines two different community initiatives. The aim is to investigate the potential incentives and barriers relating to participation or non-participation in predefined community PV projects. Qualitative, as well as quantitative empirical research was used to examine the key factors in the further development of bottom-up initiatives as contributors to a general energy transition.

Abstract

Following six decades of fastest economic and technological development in history, the current crises have been triggered by collapse of unsustainable financial systems. The extent of these contemporary interconnected crises of economic, societal, environmental, financial and other systems has also shown a need to reevaluate the measurement of sustainable development. Although the existing sustainability indicators are very complex, interdisciplinary and multidimensional, they could neither predict the onset of the crises nor their extent. Therefore relations between indicators of sustainability, technological development and happiness are presented and discussed also in terms of some of the current crises. Some possible solutions are also presented, which could be used for better measurement of life quality and could potentially replace the Gross Domestic Product as the prevailing measure of development.

Abstract

Most sources for renewable energy can be deduced from solar radiation as the main natural income of society. Contrary to conventional fossil and radioactive energy resources that are mined or pumped out from central point sources, solar energy is a de-central resource that requires area for its conversion to useful products and services. This requires a new technological as well as logistical concept for energy systems where regions play a key role as providers of energy and goods. The contribution will provide the conceptual framework for renewable energy system generation on a regional level, taking into account the responsibility of regions to provide goods and services to the larger society and to support urban centres. It will show how optimal resource-technology-demand networks may be constructed, using process network synthesis approaches and how the ecological efficiency of such regional systems can be measured. Application of these methods to real life case studies (in particular the region of Muehlviertel in Austria) will on the one hand prove the versatility of the methods presented and on the other hand will provide insight into the scope of necessary change if society moves towards a low carbon sustainable energy system.

Abstract

The Canary Islands (Spain) are highly dependent on imported oil. For 2015, the Energy Plan has established that 30% of the electricity demand will be covered by renewable energy sources, mainly wind and solar. One limitation in the Archipelago is the lack of available land. Considering both issues, land scarcity and energy goals, it is crucial to determine the photovoltaic (PV) potential on roofs. In this article, a methodology to determine the roof PV potential for small regions and/or islands is applied to the case of the Canary Islands. The results show that the potential PV production is higher than the electricity demand at competitive prices. Different scenarios depending on the use of the available roof area, economic assessment based on cost-resource curves and comparison of daily and monthly profiles (PV production versus electricity demand) have also been studied.

Abstract

Concentration of chlorophyll is an adequate parameter for assessing the trophic state of lagoon ecosystems. Objectives of this study are: selection of a system of bioindicators to enable a good qualitative evaluation of the trophic state of the lagoons and their dynamics; evaluation of seasonal water quality variability and comparison between lagoons. The trophic state of the lagoons is analysed every month over the year. Water samples are retrieved at four different sites (exact coordinates) each month, sites that are representative of different water circulation systems at each lagoon. The trophic level in the respective lagoons is thus assessed through selection of an adequate system of bioindicators, in order to observe the oscillations of the amount of chlorophyll and therefore to determine the level of eutrophication. Based on the above parameters, the comparison of the trophic state in these two lagoons has shown that they have different trophic states.

Abstract

More flexible demand side would benefit the electricity markets, networks and sustainable power generation in many ways. The success of demand response programs, however, relies on consumer acceptance. This paper reviews previous studies about acceptability of different kinds of residential demand response programs. Furthermore, it discusses whether consumers who are more aware of the principles and benefits of demand response have more positive attitudes towards demand response programs. The results of the literature review and two survey studies suggest that price and security of supply are currently bigger motives to change consumption behaviour than environmental issues and that the savings expected to trigger any action (and to lead to lasting change in behaviour) may be relatively high. Therefore, the framing of demand response programs goals may affect the acceptance. Additionally, consumers seem to prefer simple price structures that remain constant for a long time to more dynamic options.

Abstract

The present study intends to develop a high-performance solar-assisted desalination system (SADS) using multi-effect diffusion type still (MEDS) and the vacuum tube solar collector (VTSC). A MEDS prototype was designed and built. The measured result is very close to the estimation. The 10-effect MEDS will produce pure water at about 13.7 L/day/m2 collector area at a solar irradiation of 600 W/m2 and 19.7 L/day/m2 collector area at solar irradiation 800 W/m2. For 20-effect still, the yield rate increase is 32% compared to 10-effect still.

Abstract

Pervious concrete is a type of concrete with significantly increased water permeability, ensuring increased rates of drainage of rainfall. The high porosity is achieved by removing a large percentage of fine aggregates from the mix. The present paper is an approach for the addition of steel slag as a substitute for coarse aggregates in pervious concrete. More specifically, three types of aggregates have been used: steel slag, construction and demolition wastes and conventional limestone aggregates. The produced pervious concretes are compared for their properties, such as water permeability, compressive strength and abrasion behaviour. Also this paper contains the study of the porosity analysis of these pervious concrete mix designs by using porosity profiles produced from X-ray CT Scanning. According to the results of this paper, it is observed that the incorporation of industry by-products or of Construction and Demolition (C&D) wastes leads to better abrasion behaviour, and to the increase, in some cases, of the compressive strength and of the water permeability.

Abstract

This paper presents a means of estimating in-situ groundwater pH and oxidation-redox potential (ORP), two very important parameters for species migration analysis in safety assessments for radioactive waste disposal or carbon dioxide sequestration. The method was applied to a pumping test in a deep borehole drilled in a tertiary formation in Japan for validation. The following application examples are presented: when applied to several other pumping tests at the same site, it could estimate distributions of the in-situ groundwater pH and ORP; applied to multiple points selected in the groundwater database of Japan, it could help estimate the in-situ redox reaction governing the groundwater conditions in some areas.