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This work describes, photoelectrocatalytic degradation of organic pollutants by using methyl orange (an azo dye) as a model compound. The TiO2 thin film and TiO2/Cu2O composite electrodes were used as semiconductor photo electrodes. Photo catalysis by UV light Corresponding to the light intensity range of the solar light was employed with the aim of using renewable and pollutionfree energy. Result showed that the rate of removal of color was enhanced when potential bias of 1.5 V was applied. The degradation rate was also increased either in acidic (pH 2) or alkaline (pH 10) conditions. The application of a positive potential higher than the flat-band potential on the TiO2 electrode decreases the rapid charge recombination process, and enhanced the degradation of organic compound. When the TiO2/Cu2O thin film electrode was used, more efficient electron and hole separation was observed in the composite system under very low potential. It is considered that the photo-generated holes migrate towards the interface while the electrons migrate towards TiO2 and then to the back contact transparent fluorine doped tin-oxide-coated glass (TCO), making the behavior of the composite film analogous to that of an n-type semiconductor. In all cases, the kinetics of the photo catalytic oxidation of methyl orange followed a pseudo first order model and the apparent rate constant may depend on several factors such as, the nature and concentration of the organic compound, radiant flux, the solution pH and the presence of other organic substances. [ABSTRACT FROM AUTHOR]

Bosnia and Herzegovina has substantial primary energy resources and its energy industry could be profitable. This chapter presents the current status of the energy sector and the data on primary energy resources, potentials, energy infrastructure, and the production and consumption of energy. A comparison of consumption with neighbouring countries and the world is shown, as well as some energy indicators. There are ambitious plans for electric power generation in Bosnia and Herzegovina and an overview of the capacities under consideration is presented. [ABSTRACT FROM AUTHOR]

A survey of the developments in the energy sector of Macedonia is presented, including past and current activities as well as perspectives for further development. Considered are the connection between the development of the energy sector and industrial systems, the infrastructure for energy resources and perspectives on its utilisation. Attention is focused on basic problems in the development of the energy sector in Macedonia, the present energy balance, problems with the energy supply, costs and obstacles associated with imported energy, and challenges with the underdeveloped energy infrastructure and connections with neighboring countries. The review aims to provide a perspective on continued development of the energy sector as a part of the total economic development of the country. [ABSTRACT FROM AUTHOR]

The energy system in Serbia is faced with a number of challenges and inefficiencies. The technologies currently used are outdated, the equipment is old and needs to be replaced or refurbished, industrial energy consumption is high, and the energy strategy and price policies need to be revised. The current status of the energy system in Serbia is presented in this chapter, with special emphasis on energy efficiency, the use of renewable energy sources (RES) and the country's dependence on imported energy. The activities of the National Energy Efficiency Programme (NEEP), founded by the Ministry of Science and Environmental Protection, is presented in detail. Within the framework of the NEEP, 231 research, development and demonstration (R&D&D) projects and 44 feasibility studies have been financed up to now. The main aim of NEEP is to combine science and engineering in order to research, develop, demonstrate and implement efficient modern technologies and equipment, engineering and management methods and to promote the use of renewable energy sources. The Board of Directors is responsible for the choice of priorities, and the selection and control of the projects financed. NEEP has engaged the majority of the most experienced researchers and engineers in Serbia previously working in energy research. In spite of very applicable results achieved, implementation has not been successful due to lack of investment money and an unfavourable environment for the rational and efficient behaviour of the public and the companies concerned. [ABSTRACT FROM AUTHOR]

The present status of energy wood production and use in Bulgaria is considered in the framework of the current energy policy of the country, existing laws and the respective regulations, the energy market and entrepreneurship in this sector of the Bulgarian economy.We begin with an overview of Bulgarian forests and forestry and wood processing industry and then present an analysis of the structure of wooden biomass and its potential for energy production. Current status of the technology for harvesting, transportation and storage of wooden biomass is considered, followed by an overview of production of pellets and briquettes and other ways of biomass utilisation for energy production. The chapter closes with a perspective on future development of the wood chain industry in Bulgaria. [ABSTRACT FROM AUTHOR]

As amember of the EuropeanUnion, Slovenia follows a European energy policy and its objectives of a sustainable, competitive and secure supply of energy. Renewable energy sources (RES) have an important role in the global fight against climate change and are at the same time an important factor for a long-term security of energy supply.With about 11% RES share in the national primary energy balance, Slovenia is still far away from meeting its renewable energy targets. This share is slightly decreasing (12% in the year 2000) in spite of increasing use of RES. The main reason is that RES utilisation is growing slower than the primary energy (electricity) demand. However, with over 54% of the country's land covered with forest, the potential for use of solid biomass is relatively high, but it also depends on application of new utilisation technologies. Nevertheless, this type of renewable energy source has started to penetrate the market, despite many barriers. The most significant RES for electricity production is still hydro power, which in part relies on a large amount of old, small hydro power plants. Their renovation as well as the installation of additional new units is a principal part of Slovenian strategy for use of renewable energy sources. [ABSTRACT FROM AUTHOR]

We consider possible application of the state-of-the-art in technological concepts of CO2 capture and sequestration to retrofitting of low-quality coal-fired power plants. The most promising options, namely the oxy-fuel combustion and the flue gases treatment by amine scrubbing, were evaluated as retrofit options for a typical modern lignite-fired power plant. Results from thermodynamic simulations of the examined cases were used to demonstrate the potential for emissions reduction and evaluate the associated power output and efficiency penalties. Furthermore, an economic assessment of electricity production cost was carried out, in relation to the application of different existing and near future technologies. The economical impact related to fuel prices and CO2 emission risks was assessed. [ABSTRACT FROM AUTHOR]

A comparison of possible CO2 separation methods for coal-based power plant processes is considered. The requirements concerning development and research of oxy-fuel processes are presented. Steam generator concepts suited for combustion with pure oxygen are introduced, focusing on the new controlled staging with rich/lean burners. [ABSTRACT FROM AUTHOR]

In view of the threatening global environmental issues and depletion of fossil fuel resources, a hydrogen energy-oriented society is expected to be realised around 2030-2050 supported by the introduction of a large amount of renewable energy. To achieve this, however, it will take a long time and a realistic intermediate scenario is needed which is practical and socially acceptable. For this purpose, a new system integration for CO2 -free coal utilisation combined with hydrogen energy and CO2 sequestration is proposed and discussed. The method is based on the present status and future prospect of various related technologies in Japan including O2/CO2 (oxy-firing) coal combustion with CO2 recovery, hydrogen gas turbine power station, highly sophisticated utilisation of hydrogen and CO2 sequestration. [ABSTRACT FROM AUTHOR]

Technologies for capturing CO2 from power generation, that is separating CO2 from other components in a gaseous or liquid mixture, are examined from a triple point of view: of impacts of capture on performance, of costs and of pollutant emission. It is shown that there is currently no winner among the main three capture options, namely post-combustion removal of CO2 from flue gas, pre-combustion carbon removal from fuel and from oxy-combustion power systems. Although postand pre-combustion capture is an available technology in industrial applications, it must still be scaled up to the size of large power plants and from that point of view the three options are not at the same stage of development. Pilot plants are expected to be in operation in the period 2010-2015, especially in European funded projects, Europe being in the forefront of reducing strongly CO2 emissions from power plants. [ABSTRACT FROM AUTHOR]

MARS is a fission nuclear reactor developed at the Department of Nuclear Engineering and Energy Conversion of the University of Rome "La Sapienza". The design was aimed at a multipurpose, modular reactor to be used in high population density areas not only for electricity generation, but also for industrial heat production and, in particular, for water desalination or district heating. This objective, not common for nuclear power plants, required the adoption of very high safety standards not achievable by the use of conventional systems; the only viable approach was the extensive use of "passive" safety. The whole plant is assembled with special flanged connections and even major components of the primary loop, such as the reactor vessel and the steam generator, may be easily substituted or repaired. The cost of KWh is competitive with that of large reactors. [ABSTRACT FROM AUTHOR]

The currently operating light and heavy water nuclear reactors have reached a high level of safety, reliability and cost-effectiveness, demonstrated over thousands of years of cumulated operation. Mature industrial solutions are available for all stages of nuclear fuel cycles, including spent-fuel treatment, conditioning of medium-level waste, vitrification of high-level waste, and various technologies for interim storage. Considerable progress has been achieved in several countries to develop practical solutions for geological disposal of high-level, long-lived nuclear waste. To establish itself as a viable option for long-term energy production, accepted by public opinion, nuclear fission energy generation must meet the following criteria for sustainable development: (i) life-cycle cost advantage over other energy sources, together with a level of financial risk comparable to other energy projects; (ii) high-level safety and security, eliminating the need for offsite emergency response; (iii) protection of workers, population and environment against radiological hazards; (iv) minimal generation of long-lived, high-level radiotoxic waste; (v) safe disposal of all remaining waste products; (vi) optimised use of natural resources; (vii) closed fuel cycle, in harmony with the goal of "sustainability"; (viii) proliferation resistant, by fabricating the fuel so that it would be very difficult to extract fissile material from spent fuel, while minimising material accounting difficulties within the international safeguards system. This chapter aims at summarising the current status of nuclear fission energy generation vis-à-vis the above criteria. [ABSTRACT FROM AUTHOR]

In anticipation that massive production of hydrogen from renewable energy sources will not be achieved soon, we consider a distributed energy generation system using the Solid Oxide Fuel Cell (SOFC), and its hybrid system, which are characterised by fuel flexibility and high electricity generation efficiency. It is demonstrated that this system competes well in efficiency with the most advanced oil-fired large-scale combined-cycle electricity generation plants. The SOFC is very effective in reducing the emission of carbon dioxide and thus it is seen as a potential energy generation method that does not contribute to global warming. A short overview is given of the state-of-the-art of commercial type home cogeneration systems in Japan, using an SOFC or another type of fuel cell, Polymer Electrolyte Fuel Cells (PEFC). We also discuss numerical simulations of an SOFC single unit and of an SOFC stack module. These can be used as a tool for optimum design and thermal management either of an SOFC single unit or of an SOFC stacked module aimed at improving their durability and at lowering their cost. [ABSTRACT FROM AUTHOR]

The direct conversion of solar energy into hydrogen represents an attractive but challenging alternative for photovoltaic solar cells. Several metal oxide semiconductors are able to split water into hydrogen and oxygen upon illumination, but the efficiencies are still quite low. The operating principles of the photoelectrochemical device, the materials requirements, main bottlenecks, and the various device concepts will be discussed, and some promising directions for future research will be indicated. [ABSTRACT FROM AUTHOR]

Incident solar radiation is the most fundamental of the sustainable energy sources, being at the origin of all others — wind and wave, biomass and even fossil fuels which represent stored solar energy over a geological time scale. Only nuclear and geothermal sources are non-solar. The direct conversion of incident solar radiation into the most convenient energy vector, electricity, motivates the development of lower cost, higher efficiency and larger area photovoltaic devices and systems. Their history, technology and applications are here reviewed. [ABSTRACT FROM AUTHOR]

Wind energy has conquered many startup problems and has attained in a new, more mature phase. The annual market volume increases by 20-30% per year, making significant contributions to the national electricity supply in some countries (DK, DE, ES).Wind turbines have increased in size, achieved compliance with severe grid connection requirements and have cautiously gone offshore. The cost of wind-generated electricity approaches the cost of fossil-fuel-generated electricity. With this success, new challenges arise: the integration of wind energy into the electricity supply system, the step from wind turbines into (offshore) wind power plants, the associated extreme reliability requirements and the prospect of a continued cost decrease. The chapter presents the state of the art, and discusses perspectives on these issues. [ABSTRACT FROM AUTHOR]

Starting with an overview of the current state of the Russian energy situation and power industry, we consider future prospects and developments in energy production and consumption in Russia. Energy efficiency, safety, economic efficiency, and ecological safety are considered to be priorities in the further development of energy conversion utilities and in the power industry. To this purpose, the significance of the role of energy- and resource-saving techniques are considered, followed by an overview of various novel and promising technologies. [ABSTRACT FROM AUTHOR]

Sustainability has become an unavoidable issue in all major planning and undertakings that involve future use of energy, water and any other natural resources. In order to ensure sustainable growth of our society, we must satisfy the sustainability criteria and meet the constraints imposed by the finiteness of all natural resources and the dynamics of their natural renewal. But how do we quantify and measure sustainability and how do we ensure that the sustainability requirements are fulfilled? We consider the sustainability concept for energy, water and environmental systems and its interaction with current major global trends: globalisation, democratisation and decentralisation. In the assessment of global energy and water resources we consider the current resource consumption and possible scenarios for meeting future demands. We then move to the definition of the sustainability concept. In order to introduce a measure of sustainability, we focus on possible definitions of respective criteria with specific application to energy system design. It is argued that multicriteria sustainability measurements of options for an energy system must be based on four sets of indicators: technological efficiency, economic, environmental and social indicators. [ABSTRACT FROM AUTHOR]

We review the global energy situation from an anthropogenic point of view. What are the world's energy needs? How can they be satisfied in the midterm as the world population continues to grow? What kind of balance can be promoted between various sources of energy? How can we progress gradually towards a necessarily limited system, the "Earth Surface, Oceans and Atmosphere" (ESOA) system? Can we define guidelines for energy planning at local, regional and global levels? [ABSTRACT FROM AUTHOR]