- Email: [email protected]
Others, including development, economics
07 Alternative energy sources (others, including development, economics) 03/00223 Stealth wind turbines: designs and technologies to reduce visual pollution Furse, J. Refocus, 2002, 3, (2), 18-20.
03/00228 Diffusion reduction in an arbitrary scale third generation wind wave model Rogers, W. E. el al. Ocean Engineering, 2002, 29, (l 1), 1357-1390.
Protests are increasingly heard from many countries concerning visual pollution from tall wind turbine towers and it is indeed true that most modern megawatt-size models with tower heights of 50-70 m certainly stand out in the landscape. As the siting of onshore wind farms begins to encroach on the urban environment, visual pollution protests and objections are no doubt going to continue and to hinder some projects. Raising awareness of the benefits of wind farms and increased public acceptance is half of the battle in getting projects approved, but are there other less visually imposing designs and technologies that could be implemented in certain cases? This article discusses some of the relevant modern technological solutions that could help resolve or alleviate the pressing visual pollution issues of wind turbines.
The numerical schemes for the geographic propagation of random, short-crested, wind-generated waves in third-generation wave models are either unconditionally stable or only conditionally stable. Having an unconditionally stable scheme gives greater freedom in choosing the time step (for given space steps). The third-generation wave model SWAN ('Simulated WAves Nearshore') has been implemented with this type of scheme. This model uses a first order, upwind, implicit numerical scheme for geographic propagation. The scheme can be employed for both stationary (typically small scale) and non-stationary (i.e. time-stepping) computations. Though robust, this first order scheme is very diffusive. This degrades the accuracy of the model in a number of situations, including most model applications at larger scales. The authors reduce the diffusiveness of the model by replacing the existing numerical scheme with two alternative higher order schemes, a scheme that is intended for stationary, small-scale computations, and a scheme that is most appropriate for nonstationary computations. Examples representative of both large-scale and small-scale applications are presented. The alternative schemes are shown to be much less diffusive than the original scheme while retaining the implicit character of the particular SWAN set-up. The additional computational burden of the stationary alternative scheme is negligible, and the expense of the non-stationary alternative scheme is comparable to those used by other third generation wave models. To further accommodate large-scale applications of SWAN, the model is reformulated in terms of spherical coordinates rather than the original Cartesian coordinates. Thus the modified model can calculate wave energy propagation accurately and efficiently at any scale.
03/00224
Substitution potential of wind energy in Egypt
EI-Sayed, M. A. H. Energy Policy, 2002, 30, (8), 681-687. The amount of energy generated by conventional power plants is expected to decline in near future due to environmental concern and the possible penetration of renewable energy such as wind generation. Therefore, the evaluation of the substitution potential of wind energy is becoming an important task by generation planning of power systems. A new methodology for estimating the capacity credit due to wind generation is developed based on the convolution technique considering the statistical wind speed variations. Moreover, the economic impact of wind energy is assessed in the form of cost/benefit ratio to justify the substitution potential of such clean energy resource. The feasibility of the proposed approaches are illustrated using the planned 600 MW wind farm in Za'afarana, which would be integrated to the Egyptian unified power network.
03/00225 Wind energy in urban areas: concentrator effects for wind turbines close to buildings Mertens, S. et al. Refocus, 2002, 3, (2), 22-24.
03/00229 Green energy in Europe: selling green energy with green certificates Ouillet, L. Refocus, 2002, 3, (2), 52.
One often overlooked alternative to conventional large-scale wind farms is to produce wind energy close to where we need it such as in the built environment. In this case we do not need to transport the energy and we keep rural areas untouched. However, the built environment has lower average wind speeds and higher turbulence levels. What means do we have to compensate for this? This article describes some of the specific technology and design issues in the use of wind energy in buildings.
Sales of green power products are booming in Europe: 50 000 customers in the United Kingdom, 775 000 in the Netherlands and 300 000 in Germany. Laws of physics are however formal: the way in which electricity flows within the grid does not allow suppliers to assure customers that they are directly receiving electricity produced exclusively from renewable energy sources. What are marketers selling their green energy customers then? This article takes a closer look and focuses on the potential of selling green energy in the form of renewable energy certificates.
03/00226 Wind farm planning consents: meeting renewables targets or national security - a conflict? Cassidy, P. Re[ocus, 2002, 3, (2), 50-51.
03/00230 Greening products: a framework for product chain management Boons, F. Journal of Cleaner Production, 2002, 10, (5), 495-505.
On 14 December 2001, a preliminary hearing was held in the High Court of justice in the UK. The purpose of the hearing was to decide whether EcoGen Developments Limited (EcoGen) had the right for a full judicial review, following the Secretary of State for Trade and Industry's (SSTI) decision, on 29 March 2001, to block the development of an 80MW onshore wind farm at Humble Hill, Northumberland, UK. This paper takes a closer look at the decision and what it may mean for obtaining planning consent for wind farms in certain parts of the UK.
Others, including development, economics 03100227
Carbon sequestration in agroforestry systems
Pandey, D. N. Climate Policy, 2002, Management of trees in agroecosystems such as agroforestry, ethnoforests, and trees outside forests can mitigate green house gas (GHG) emissions under the Kyoto Protocol. Agroforestry systems are a better climate change mitigation option than oceanic, and other terrestrial options because of the secondary environmental benefits such as helping to attain food security and secure land tenure in developing countries, increasing farm income, restoring and maintaining aboveground and below-ground biodiversity, corridors between protected forests, as CH4 sinks, maintaining watershed hydrology, and soil conservation. Agroforestry also mitigates the demand for wood and reduces pressure on natural forests. Promoting woodcarving industry facilitates long-term locking-up of carbon in carved wood and new sequestration through intensified tree growing. By making use of local knowledge, equity, livelihood security, trade and industry, can be supported. There is need to support development of suitable policies, assisted by robust country-wide scientific studies aimed at better understanding the potential of agroforestry and etbnoforestry for climate change mitigation and human well-being.
Diminishing the ecological effects of products has become an important focus of corporate environmental strategies. Based on empirical research by the author and published sources, this paper presents a conceptual framework of six types of product chain management. By looking at several categories costs and benefits for different actors (suppliers, producers, distributors, consumers) associated with each of these types, the framework focuses on their differential nature. In addition, the diversity in strategies open to each of these actors in the product chain is a main focus of the paper. The use of the framework as an analytical as well as an interventionist tool is discussed.
03/00231 Latching control of deep water wave energy devices using an active reference Korde, U. A. Ocean Engineering, 2002, 29, (l 1), 1343-1355. This paper investigates latching type control on a floating wave energy converter in deep water. An on-board, actively controlled motioncompensated platform is used as a reference ('active reference') for power absorption and latching. A variational formulation is used to evaluate an optimal control sequence in the time domain, Time domain simulation results are presented for a heaving buoy in small-amplitude waves. Results are compared with an equivalent system where latching and power absorption are from a sea-bottom-fixed reference.
03/00232 Neuro-fuzzy control for autonomous wind-diesel systems using biomass Jurado, F. and Saenz, J. Renewable Energy, 2002, 27, (1), 39-56. This paper deals with the development of a neuro-fuzzy controller for a wind-diesel system composed of a stall regulated wind turbine with an induction generator connected to an ac bus-bar in parallel with a diesel generator set having a synchronous generator. A gasifier is capable of converting tons of wood chips per day into a gaseous fuel that is fed into a diesel engine. The controller inputs are the engine speed error and its derivative for the governor part of the controller, and the voltage error and its derivative for the automatic voltage regulator. These are readily measurable quantities leading to a simple controller which can be easily implemented. It is shown that by tuning the fuzzy logic controllers, optimal time domain performance of the autonomous
Fuel and Energy Abstracts
January 2003
29
07 Alternative energy sources (others, including development, economics) wind-diesel system ean be achieved in a wide range of operating conditions compared to fixed-parameter fuzzy logic controllers and PID controllers.
03/00233 Overview of renewable energy sources in the Republic of the Sudan Omer, A. M. Energy, 2002, 27, (6), 523-547. Sudan is an agricultural country with fertile land, plenty of water resources, livestock, forestry resources and agricultural residues. An overview of the energy situation in Sudan is introduced with reference to the end uses and regional distribution. Energy sources are divided into two main types: conventional energy (biomass, petroleum products and electricity) and non-conventional energy (solar, wind, hydro, etc.). Sudan possesses a relatively high abundance of solar radiation, moderate wind speeds, hydro and biomass energy resources. Application of new and renewable sources of energy available in Sudan is now a major issue in strategic planning for alternatives to fossil fuels to provide part of local energy demand. Sudan is an important case study in the context of renewable energy. It has a long history of meeting its energy needs through renewables. Sudan's renewables portfolio is broad and diverse, due in part to the country's wide range of climates and landscapes. Like many of the African leaders in renewable energy utilization, Sudan has a well-defined commitment to continue research, development and implementation of new technologies. Sustainable low-carbon energy scenarios for the new century emphasize the untapped potential of renewable resources. Rural areas of Sudan can benefit from this transition. The increased availability of reliable and efficient energy services stimulates new development alternatives. Renewable environmentally friendly energy must be encouraged, promoted, implemented and demonstrated, for use in the Republic of the Sudan.
03•00234 Pathways to a more sustainable production of energy: sustainable hydrogen - a research objective for Shell Gosselink, J. W. International Journal el Hydrogen Energy, 2002, 27, (11-12), 1125-1129. Towards a sustainable energy supply is a clear direction for exploratory research in Shell. Examples of energy carriers, which should be delivered to the envisaged sustainable energy markets, are bio-fuels, produced from biomass residues, and hydrogen (or electricity), produced from renewable sources. In contrast to the readily available ancient sunlight stored in fossil fuels, the harvesting of incident sunlight will be intermittent, efficient electricity and hydrogen storage technologies need to be developed. Research to develop those energy chains is going on, but the actual transformation from current fossil fuel based to sustainable energy markets will take a considerable time. In the meantime the fossil fuel-based energy markets have to be transformed to mitigate the impact of the use of fossil fuels. Some elements in this transformation are fuels for ultra-clean combustion (hydrocarbons and oxygenates), hydrogen from fossil fuels, fuels for processors for fuel cells, carbon sequestration.
03/00235 Potential of extremophiles for biotechnological and petroleum applications Tango, M. S. A. and Islam, M. R. Energy Sources, 2002, 24, (6), 534559. The ability of microorganisms to survive under harsh conditions has recently prompted researchers to study these .microbes to better understand their characteristics and eventually utilize them in various applications. Extremophilic microorganisms withstand one or more extreme condition constraints due to cold, heat, high acidity, high alkalinity, high salinity, and high pressure levels. These constraints would destroy normal microorganisms. Extremophiles can be classified according to the environment in which they survive. Many extremophilie microorganisms possess properties suitable for biotechnological and commercial uses. This article discusses the characteristics and future potentials of extremophiles.
03/00236 a review
Renewable and sustainable energy use in Turkey:
Kaygusuz, K. Renewable and Sustainable Energy Reviews, 2002, 6, (4), 339-366. Turkey is an energy importing nation with more than half of its energy requirements met by imported fuels. Air pollution is becoming a significant environmental concern in the country. In this regard, renewable energy resources are becoming attractive for sustainable energy development and environmental pollution mitigation in Turkey. Turkey's geographical location has several advantages for extensive use of m o s t of these renewable energy sources. Because of this and the limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be a serious alternative for Turkey's energy future. This article presents a review of the present energy situation and assesses sustainability, technical, and economical potential of renewable energy sources, and future policies for the energy sector in Turkey.
30
Fuel and Energy Abstracts
January 2003
Throughout the paper, problems relating to renewable energy sources, environment, and sustainable development are discussed for both current and future energy investments. The renewable energy potential of the country and its present status are evaluated.
03•00237 Renewable energy sources project appraisal under uncertainty: the case of wind energy exploitation within a changing energy market environment Venetsanos, K. et al. Energy Policy, 2002, 30, (4), 293-307. There are four elements which contribute to the oncoming increase of electricity demand; climate changes, the expected growth rates of EU Member State economies, changes in the consumption patterns and the introduction of new technologies. The new deregulated electricity market is expected to respond to this challenge and the energy supply will be adequate and cost effective within this new environment which offers promising opportunities for power producers both existing and newcomers. In this paper a framework for the appraisal of power projects under uncertainty within a competitive market environment is identified, focusing on the electricity from renewable energy sources. To this end the wind energy-to-electricity production in Greece will serve as a case study. The subject matter is centred on the following areas: (1) the uncertainties within the new deregulated energy market; (2) the evaluation methods including an analysis of the introduced uncertainties after deregulation and a new approach to project evaluation using the real options, as well as comparison of the valuation methodologies within the new environment drawing from the case for Greece.
03100238
Renewable energy storage: the missing link
Marsh, G. Re[ocus, 2002, 3, (2), 38-41. Because the supply of renewable energies may not coincide with demand, energy storage must provide the missing link. Though this key enabler has been overshadowed by more glamorous generating technologies, innovation in this sector is crucial for a renewablesbased future.
03•00239
Renewables: a US congressman's view
Udall, M. Refocus, 2002, 3, (2), 48-49. US Representative Mark Uda[I is a key leader in the effort to expand the adoption and development of renewable energy. Udall's role as cochair of the US House of Representatives' Renewable Energy and Energy Efficiency Caucus has placed him in a central position in terms of influencing US federal government renewable energy policy. This article looks at his enthusiastic involvement on renewable energy matters may portend a brighter future for US policy.
03100240 resource
Rent-seeking and quota regulation of a renewable
Bergland, H. et al. Resource and Energy Economics, 2002, 24, (3), 263279. This paper deals with rent-seeking behaviour among agents who compete for future shares of a common renewable natural resource. Rent-seeking might become profitable when the agents expect that the distribution of the natural resource in the coming periods will be dependent on the agents' extraction of the resource in the past, even though high exploitation might reduce the stock that future individual quotas will be based upon. Whether aggressive rent-seeking behaviour by one agent will encourage other agents to rent-seek more, however, is generally found to be ambiguous.
03/00241
Review of biomass energy in Turkey
Kaygusuz, K. and Tiirker, M. F. Energy Sources, 2002, 24, (5), 383401. Biomass energies, including fuelwood, agricultural residues, animal wastes, charcoal, and other fuels derived from biological sources, are a promising option with a potentially large impact for developing countries, where the current levels of energy services are low. Biomass accounts for about one-third of all energy in developing countries as a whole and nearly 90% in some of the least developed countries. In the case of Turkey, biomass has great potential to provide improved rural energy services based on forest and agricultural residues. The present study gives a review of the production, consumption, and economics of biomass energy for sustainable development in Turkey. In 1999, the biomass share of the total energy consumption of the country was 10%. In this study, the potential for important biomass energy sources and animal solid wastes of the country were determined. Considering total cereal products and fatty seed plants, approximately 50-60 million tons per year of biomass and 8-10 million tons of solid matter animal waste are produced, and 70% of total biomass is seen as possible for use for energy. Some useful suggestions and recommendations are also presented.
08 Steam raising (boiler operation~design) 03/00242
Sustainable building
Anon, Refocus, 2002, 3, (2), 56-58. Sustainable building is a hot topic at the moment because building integrated technologies such as photovohaics (BIPV) and solar thermal are becoming more and more accessible both economically and in terms of ease-of-use. The number of developments that choose to utilize these technologies is still relatively small but it is growing and buildings that do employ sustainability serve as an example to others. Two examples from Scandinavia are considered in this article - the Klosterenga Ecology Dwellings in Oslo, Norway, and a new community centre in Kolding in Denmark.
03/00243 Sustainable development of rural energy and its appraising system in Chin~,~ Wang, X. and Feng, Z. Rene~va~le and Sustainable Energy Reviews, 2002, 6, (4), 395-404. The local biomass resources have been used in rural China for quite a long time, which has a close connection with and will inevitably affect the environment. In recent years, China has experienced rapid economic growth and equally rapid increases in energy use, especially commercial energy, in rural areas. As a result, energy induced environmental degradation has also increased in rural China. This paper discusses the relationship between China's rural energy and its sustainable development. It brings forward the index system for appraising the sustainable development of rural energy (SDRE), calculates the weighing of each index with analytic hierarchy process (AHP), puts forward the quantification method and provides the basis for the research of the rural energy for sustainable development in different areas and periods.
03/00244 The growth productivity, and environmental impact of the cultivation of energy crops on sandy soil in Germany Scholz, V. and Ellerbrock, R. Biomass and Bioenergy, 2002, 23, (2), 8192. Energy plants, cultivated on set-aside land, could substitute nearly 3% of the primary energy in Germany and could raise income of farmers. However, the substitution of fossil fuels by plants requires the selection of plant species with high site suitability, an ecologically benign farming system and high yields. This paper describes results of the cultivation of 10 energy plant species suitable for combustion. Over a period of 6 year, yield, energy gain, and environmentally relevant substances in the plant and the soil were determined under practical conditions. Fertilization was carried out in four variants each ranging from 0 to 150 kg N ha -1 and with wood- and straw ashes, as well as basic mineral fertilizer. Plant protection products were entirely dispensed with. The results show that, except for Topinambur haulm (Jerusalem artichoke) and short rotation coppice with undersown crops, the mean yield ranges between 8 and 12 tDM h a ~ and that a reduction of nitrogen application from 150 to 75 kg N ha i causes only slight yield losses. Without fertilization, yields diminish by 20-40% after 6 years, except for poplars, which reach similarly a high yield level as with fertilization. The contents of the emission- and combustion-relevant plant nutrients, such as nitrogen, potassium, sulfur and chlorine, are significantly lower in poplars and willows than in grass, rye, triticale and hemp. Heavy metals, such as cadmium, copper, zinc, and lead, are absorbed differently. Hemp, poplars, and winter rye allow high-energy yields to be achieved. Even if nitrogen fertilization is reduced, net energy gains of more than 120 GJ ha i year i (3.2 kl oil equivalent ha year -t ) are reached.
03/00245 The potential contribution of renewable energy in air pollution abatement in China and India Boudri, J. C. et al. Energy Policy, 2002, 30, (5), 409-424. The potential for the use of renewable sources of energy in China and India and their cost effectiveness in air pollution abatement in Asia is studied. This is done through an integrated assessment of the costs and the environmental impacts of several types of renewables, in comparison with fossil fuels. Results for different scenarios for fuel use in China and India for the period 1990-2020 are presented. The acidification model R A I N S - A S I A is used to analyse environmental impacts (exceedance of critical loads for acidification) and to perform an optimization analysis, aiming at minimizing abatement costs. The costs of controlling the emissions from fossil fuels (e.g. through flue gas desulfurization). For the environmental targets analysed in this study an increased use of renewable energy could cut SO2 emission-control costs in China by 17-35%, and in India by more than two thirds.
03/00246 Wave energy in Europe: current status and perspectives Cl~.ment, A. et al. Renewable and Sustainable Energy Revien's, 2002, 6, (5), 405-431. The progress in wave energy conversion in Europe during the past ten years is reviewed and current activities and initiatives in the wave energy sector at National and Union level are described. Other
important activities worldwide are summarized. The technical and economical status in wave energy conversion is outlined and important wave energy developments are presented.
08
STEAM RAISING Boiler operation/design
03•00247 Combined cycle plant efficiency increase based on the optimization of the heat recovery steam generator operating parameters Franco, A. and Russo, A. International Journal qf Thermal Sciences, 2002, 41, (9), 843-859. Combined cycle (CC) power plants allow the growing energy demand to be met with the least fuel consumption. Thus it is of great interest to define a strategy for the optimization of these systems, in order to get greater performances and efficiency from them. The objective of most manufacturers would be to reach an overall thermal efficiency of 60% in the short-term period, by improving the gas turbine inlet temperature. In this paper, it is shown how it could be possible to reach the same performances by best fitting the existing technology. In particular attention is directed to the optimization of the heat recovery steam generator (HRSG), as a first step in the analysis of the whole plant, according to a hierarchical strategy. The problem is handled by adopting both a thermodynamic and a thermoeconomic objective function instead that with the usual pinch point method. Thermodynamic optimization has the purpose to diminish energy losses, expressed on exergy basis, while the aim of the thermoeconomic optimization is the minimization of a cost function, sum of the cost of exergy inefficiencies and the cost of the HRSG. Proposed methods have been applied to some HRSG configurations, including some present commercial plants. The results of the application of the thermoeconomic optimization leads to a meaningful increase of the thermal efficiency of the plant that approaches the 60%, obtained with and increases of the heat surface and a decrease of the pinch-points. The economic evaluations are referred to US dollars ($) even if the costs are referred to European scenario, assuming US$1 = El.1.
03/00248 Computer simulation and visualization of the thermodynamic properties of steam and steam processes Barakat, M. H. Energy Sources, 2002, 24, (33, 247-261. Process simulation programs based on water and steam as a working fluid require the feed of thermodynamic properties during the program runtime. This paper presents the mathematical model necessary to identify the phase and to simulate the thermodynamic properties of water, steam, and wet steam at different temperatures and pressures. The simulated values are compared to the tabulated values and the deviation errors are indicated. A computer program is constructed and visual presentation of the properties on an interactive interface, as well as by plotting on the enthalpy-entropy chart, are presented.
03100249 High temperature air combustion boiler for low BTU gas Kawai, K. el al. Energy Conversion and Management, 2002, 43, (9-12), 1563-1570. A new concept boiler where fuel can be efficiently combusted by high temperature preheated air is proposed and experimental demonstration is done. This boiler is suitable for low BTU gas derived from gasification process of coal and wastes with no dioxin emission. This boiler is characterized by the following features: uniform heat flux field, augmentation of heat transfer, reduction of combustion noise level, suppression of NO, emission and compactness. Preliminary experiments using natural gas as a fuel demonstrate above distinct performance as well as good agreement with three-dimensional numerical simulation.
03/00250 Methods of choosing the optimal parameters for solid fuel combustion in stoker-fired boilers Rusinowski, H. et al. Energy Conversion and Management, 2002, 43, (9123, 1363-1375. Stoker-fired boilers are used for the combustion of coal and solid wastes. The most important disadvantage is their low thermal efficiency. The authors present methods of choosing the optimal rate of travel of the grid and height of the fuel layer basing on both real scale and laboratory measurements. Basing on industrial-scale experiments the authors calculated the optimal thermal efficiency and main
Fuel and Energy Abstracts January 2003 31
03/00228 Diffusion reduction in an arbitrary scale third generation wind wave model Rogers, W. E. el al. Ocean Engineering, 2002, 29, (l 1), 1357-1390.
Protests are increasingly heard from many countries concerning visual pollution from tall wind turbine towers and it is indeed true that most modern megawatt-size models with tower heights of 50-70 m certainly stand out in the landscape. As the siting of onshore wind farms begins to encroach on the urban environment, visual pollution protests and objections are no doubt going to continue and to hinder some projects. Raising awareness of the benefits of wind farms and increased public acceptance is half of the battle in getting projects approved, but are there other less visually imposing designs and technologies that could be implemented in certain cases? This article discusses some of the relevant modern technological solutions that could help resolve or alleviate the pressing visual pollution issues of wind turbines.
The numerical schemes for the geographic propagation of random, short-crested, wind-generated waves in third-generation wave models are either unconditionally stable or only conditionally stable. Having an unconditionally stable scheme gives greater freedom in choosing the time step (for given space steps). The third-generation wave model SWAN ('Simulated WAves Nearshore') has been implemented with this type of scheme. This model uses a first order, upwind, implicit numerical scheme for geographic propagation. The scheme can be employed for both stationary (typically small scale) and non-stationary (i.e. time-stepping) computations. Though robust, this first order scheme is very diffusive. This degrades the accuracy of the model in a number of situations, including most model applications at larger scales. The authors reduce the diffusiveness of the model by replacing the existing numerical scheme with two alternative higher order schemes, a scheme that is intended for stationary, small-scale computations, and a scheme that is most appropriate for nonstationary computations. Examples representative of both large-scale and small-scale applications are presented. The alternative schemes are shown to be much less diffusive than the original scheme while retaining the implicit character of the particular SWAN set-up. The additional computational burden of the stationary alternative scheme is negligible, and the expense of the non-stationary alternative scheme is comparable to those used by other third generation wave models. To further accommodate large-scale applications of SWAN, the model is reformulated in terms of spherical coordinates rather than the original Cartesian coordinates. Thus the modified model can calculate wave energy propagation accurately and efficiently at any scale.
03/00224
Substitution potential of wind energy in Egypt
EI-Sayed, M. A. H. Energy Policy, 2002, 30, (8), 681-687. The amount of energy generated by conventional power plants is expected to decline in near future due to environmental concern and the possible penetration of renewable energy such as wind generation. Therefore, the evaluation of the substitution potential of wind energy is becoming an important task by generation planning of power systems. A new methodology for estimating the capacity credit due to wind generation is developed based on the convolution technique considering the statistical wind speed variations. Moreover, the economic impact of wind energy is assessed in the form of cost/benefit ratio to justify the substitution potential of such clean energy resource. The feasibility of the proposed approaches are illustrated using the planned 600 MW wind farm in Za'afarana, which would be integrated to the Egyptian unified power network.
03/00225 Wind energy in urban areas: concentrator effects for wind turbines close to buildings Mertens, S. et al. Refocus, 2002, 3, (2), 22-24.
03/00229 Green energy in Europe: selling green energy with green certificates Ouillet, L. Refocus, 2002, 3, (2), 52.
One often overlooked alternative to conventional large-scale wind farms is to produce wind energy close to where we need it such as in the built environment. In this case we do not need to transport the energy and we keep rural areas untouched. However, the built environment has lower average wind speeds and higher turbulence levels. What means do we have to compensate for this? This article describes some of the specific technology and design issues in the use of wind energy in buildings.
Sales of green power products are booming in Europe: 50 000 customers in the United Kingdom, 775 000 in the Netherlands and 300 000 in Germany. Laws of physics are however formal: the way in which electricity flows within the grid does not allow suppliers to assure customers that they are directly receiving electricity produced exclusively from renewable energy sources. What are marketers selling their green energy customers then? This article takes a closer look and focuses on the potential of selling green energy in the form of renewable energy certificates.
03/00226 Wind farm planning consents: meeting renewables targets or national security - a conflict? Cassidy, P. Re[ocus, 2002, 3, (2), 50-51.
03/00230 Greening products: a framework for product chain management Boons, F. Journal of Cleaner Production, 2002, 10, (5), 495-505.
On 14 December 2001, a preliminary hearing was held in the High Court of justice in the UK. The purpose of the hearing was to decide whether EcoGen Developments Limited (EcoGen) had the right for a full judicial review, following the Secretary of State for Trade and Industry's (SSTI) decision, on 29 March 2001, to block the development of an 80MW onshore wind farm at Humble Hill, Northumberland, UK. This paper takes a closer look at the decision and what it may mean for obtaining planning consent for wind farms in certain parts of the UK.
Others, including development, economics 03100227
Carbon sequestration in agroforestry systems
Pandey, D. N. Climate Policy, 2002, Management of trees in agroecosystems such as agroforestry, ethnoforests, and trees outside forests can mitigate green house gas (GHG) emissions under the Kyoto Protocol. Agroforestry systems are a better climate change mitigation option than oceanic, and other terrestrial options because of the secondary environmental benefits such as helping to attain food security and secure land tenure in developing countries, increasing farm income, restoring and maintaining aboveground and below-ground biodiversity, corridors between protected forests, as CH4 sinks, maintaining watershed hydrology, and soil conservation. Agroforestry also mitigates the demand for wood and reduces pressure on natural forests. Promoting woodcarving industry facilitates long-term locking-up of carbon in carved wood and new sequestration through intensified tree growing. By making use of local knowledge, equity, livelihood security, trade and industry, can be supported. There is need to support development of suitable policies, assisted by robust country-wide scientific studies aimed at better understanding the potential of agroforestry and etbnoforestry for climate change mitigation and human well-being.
Diminishing the ecological effects of products has become an important focus of corporate environmental strategies. Based on empirical research by the author and published sources, this paper presents a conceptual framework of six types of product chain management. By looking at several categories costs and benefits for different actors (suppliers, producers, distributors, consumers) associated with each of these types, the framework focuses on their differential nature. In addition, the diversity in strategies open to each of these actors in the product chain is a main focus of the paper. The use of the framework as an analytical as well as an interventionist tool is discussed.
03/00231 Latching control of deep water wave energy devices using an active reference Korde, U. A. Ocean Engineering, 2002, 29, (l 1), 1343-1355. This paper investigates latching type control on a floating wave energy converter in deep water. An on-board, actively controlled motioncompensated platform is used as a reference ('active reference') for power absorption and latching. A variational formulation is used to evaluate an optimal control sequence in the time domain, Time domain simulation results are presented for a heaving buoy in small-amplitude waves. Results are compared with an equivalent system where latching and power absorption are from a sea-bottom-fixed reference.
03/00232 Neuro-fuzzy control for autonomous wind-diesel systems using biomass Jurado, F. and Saenz, J. Renewable Energy, 2002, 27, (1), 39-56. This paper deals with the development of a neuro-fuzzy controller for a wind-diesel system composed of a stall regulated wind turbine with an induction generator connected to an ac bus-bar in parallel with a diesel generator set having a synchronous generator. A gasifier is capable of converting tons of wood chips per day into a gaseous fuel that is fed into a diesel engine. The controller inputs are the engine speed error and its derivative for the governor part of the controller, and the voltage error and its derivative for the automatic voltage regulator. These are readily measurable quantities leading to a simple controller which can be easily implemented. It is shown that by tuning the fuzzy logic controllers, optimal time domain performance of the autonomous
Fuel and Energy Abstracts
January 2003
29
07 Alternative energy sources (others, including development, economics) wind-diesel system ean be achieved in a wide range of operating conditions compared to fixed-parameter fuzzy logic controllers and PID controllers.
03/00233 Overview of renewable energy sources in the Republic of the Sudan Omer, A. M. Energy, 2002, 27, (6), 523-547. Sudan is an agricultural country with fertile land, plenty of water resources, livestock, forestry resources and agricultural residues. An overview of the energy situation in Sudan is introduced with reference to the end uses and regional distribution. Energy sources are divided into two main types: conventional energy (biomass, petroleum products and electricity) and non-conventional energy (solar, wind, hydro, etc.). Sudan possesses a relatively high abundance of solar radiation, moderate wind speeds, hydro and biomass energy resources. Application of new and renewable sources of energy available in Sudan is now a major issue in strategic planning for alternatives to fossil fuels to provide part of local energy demand. Sudan is an important case study in the context of renewable energy. It has a long history of meeting its energy needs through renewables. Sudan's renewables portfolio is broad and diverse, due in part to the country's wide range of climates and landscapes. Like many of the African leaders in renewable energy utilization, Sudan has a well-defined commitment to continue research, development and implementation of new technologies. Sustainable low-carbon energy scenarios for the new century emphasize the untapped potential of renewable resources. Rural areas of Sudan can benefit from this transition. The increased availability of reliable and efficient energy services stimulates new development alternatives. Renewable environmentally friendly energy must be encouraged, promoted, implemented and demonstrated, for use in the Republic of the Sudan.
03•00234 Pathways to a more sustainable production of energy: sustainable hydrogen - a research objective for Shell Gosselink, J. W. International Journal el Hydrogen Energy, 2002, 27, (11-12), 1125-1129. Towards a sustainable energy supply is a clear direction for exploratory research in Shell. Examples of energy carriers, which should be delivered to the envisaged sustainable energy markets, are bio-fuels, produced from biomass residues, and hydrogen (or electricity), produced from renewable sources. In contrast to the readily available ancient sunlight stored in fossil fuels, the harvesting of incident sunlight will be intermittent, efficient electricity and hydrogen storage technologies need to be developed. Research to develop those energy chains is going on, but the actual transformation from current fossil fuel based to sustainable energy markets will take a considerable time. In the meantime the fossil fuel-based energy markets have to be transformed to mitigate the impact of the use of fossil fuels. Some elements in this transformation are fuels for ultra-clean combustion (hydrocarbons and oxygenates), hydrogen from fossil fuels, fuels for processors for fuel cells, carbon sequestration.
03/00235 Potential of extremophiles for biotechnological and petroleum applications Tango, M. S. A. and Islam, M. R. Energy Sources, 2002, 24, (6), 534559. The ability of microorganisms to survive under harsh conditions has recently prompted researchers to study these .microbes to better understand their characteristics and eventually utilize them in various applications. Extremophilic microorganisms withstand one or more extreme condition constraints due to cold, heat, high acidity, high alkalinity, high salinity, and high pressure levels. These constraints would destroy normal microorganisms. Extremophiles can be classified according to the environment in which they survive. Many extremophilie microorganisms possess properties suitable for biotechnological and commercial uses. This article discusses the characteristics and future potentials of extremophiles.
03/00236 a review
Renewable and sustainable energy use in Turkey:
Kaygusuz, K. Renewable and Sustainable Energy Reviews, 2002, 6, (4), 339-366. Turkey is an energy importing nation with more than half of its energy requirements met by imported fuels. Air pollution is becoming a significant environmental concern in the country. In this regard, renewable energy resources are becoming attractive for sustainable energy development and environmental pollution mitigation in Turkey. Turkey's geographical location has several advantages for extensive use of m o s t of these renewable energy sources. Because of this and the limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be a serious alternative for Turkey's energy future. This article presents a review of the present energy situation and assesses sustainability, technical, and economical potential of renewable energy sources, and future policies for the energy sector in Turkey.
30
Fuel and Energy Abstracts
January 2003
Throughout the paper, problems relating to renewable energy sources, environment, and sustainable development are discussed for both current and future energy investments. The renewable energy potential of the country and its present status are evaluated.
03•00237 Renewable energy sources project appraisal under uncertainty: the case of wind energy exploitation within a changing energy market environment Venetsanos, K. et al. Energy Policy, 2002, 30, (4), 293-307. There are four elements which contribute to the oncoming increase of electricity demand; climate changes, the expected growth rates of EU Member State economies, changes in the consumption patterns and the introduction of new technologies. The new deregulated electricity market is expected to respond to this challenge and the energy supply will be adequate and cost effective within this new environment which offers promising opportunities for power producers both existing and newcomers. In this paper a framework for the appraisal of power projects under uncertainty within a competitive market environment is identified, focusing on the electricity from renewable energy sources. To this end the wind energy-to-electricity production in Greece will serve as a case study. The subject matter is centred on the following areas: (1) the uncertainties within the new deregulated energy market; (2) the evaluation methods including an analysis of the introduced uncertainties after deregulation and a new approach to project evaluation using the real options, as well as comparison of the valuation methodologies within the new environment drawing from the case for Greece.
03100238
Renewable energy storage: the missing link
Marsh, G. Re[ocus, 2002, 3, (2), 38-41. Because the supply of renewable energies may not coincide with demand, energy storage must provide the missing link. Though this key enabler has been overshadowed by more glamorous generating technologies, innovation in this sector is crucial for a renewablesbased future.
03•00239
Renewables: a US congressman's view
Udall, M. Refocus, 2002, 3, (2), 48-49. US Representative Mark Uda[I is a key leader in the effort to expand the adoption and development of renewable energy. Udall's role as cochair of the US House of Representatives' Renewable Energy and Energy Efficiency Caucus has placed him in a central position in terms of influencing US federal government renewable energy policy. This article looks at his enthusiastic involvement on renewable energy matters may portend a brighter future for US policy.
03100240 resource
Rent-seeking and quota regulation of a renewable
Bergland, H. et al. Resource and Energy Economics, 2002, 24, (3), 263279. This paper deals with rent-seeking behaviour among agents who compete for future shares of a common renewable natural resource. Rent-seeking might become profitable when the agents expect that the distribution of the natural resource in the coming periods will be dependent on the agents' extraction of the resource in the past, even though high exploitation might reduce the stock that future individual quotas will be based upon. Whether aggressive rent-seeking behaviour by one agent will encourage other agents to rent-seek more, however, is generally found to be ambiguous.
03/00241
Review of biomass energy in Turkey
Kaygusuz, K. and Tiirker, M. F. Energy Sources, 2002, 24, (5), 383401. Biomass energies, including fuelwood, agricultural residues, animal wastes, charcoal, and other fuels derived from biological sources, are a promising option with a potentially large impact for developing countries, where the current levels of energy services are low. Biomass accounts for about one-third of all energy in developing countries as a whole and nearly 90% in some of the least developed countries. In the case of Turkey, biomass has great potential to provide improved rural energy services based on forest and agricultural residues. The present study gives a review of the production, consumption, and economics of biomass energy for sustainable development in Turkey. In 1999, the biomass share of the total energy consumption of the country was 10%. In this study, the potential for important biomass energy sources and animal solid wastes of the country were determined. Considering total cereal products and fatty seed plants, approximately 50-60 million tons per year of biomass and 8-10 million tons of solid matter animal waste are produced, and 70% of total biomass is seen as possible for use for energy. Some useful suggestions and recommendations are also presented.
08 Steam raising (boiler operation~design) 03/00242
Sustainable building
Anon, Refocus, 2002, 3, (2), 56-58. Sustainable building is a hot topic at the moment because building integrated technologies such as photovohaics (BIPV) and solar thermal are becoming more and more accessible both economically and in terms of ease-of-use. The number of developments that choose to utilize these technologies is still relatively small but it is growing and buildings that do employ sustainability serve as an example to others. Two examples from Scandinavia are considered in this article - the Klosterenga Ecology Dwellings in Oslo, Norway, and a new community centre in Kolding in Denmark.
03/00243 Sustainable development of rural energy and its appraising system in Chin~,~ Wang, X. and Feng, Z. Rene~va~le and Sustainable Energy Reviews, 2002, 6, (4), 395-404. The local biomass resources have been used in rural China for quite a long time, which has a close connection with and will inevitably affect the environment. In recent years, China has experienced rapid economic growth and equally rapid increases in energy use, especially commercial energy, in rural areas. As a result, energy induced environmental degradation has also increased in rural China. This paper discusses the relationship between China's rural energy and its sustainable development. It brings forward the index system for appraising the sustainable development of rural energy (SDRE), calculates the weighing of each index with analytic hierarchy process (AHP), puts forward the quantification method and provides the basis for the research of the rural energy for sustainable development in different areas and periods.
03/00244 The growth productivity, and environmental impact of the cultivation of energy crops on sandy soil in Germany Scholz, V. and Ellerbrock, R. Biomass and Bioenergy, 2002, 23, (2), 8192. Energy plants, cultivated on set-aside land, could substitute nearly 3% of the primary energy in Germany and could raise income of farmers. However, the substitution of fossil fuels by plants requires the selection of plant species with high site suitability, an ecologically benign farming system and high yields. This paper describes results of the cultivation of 10 energy plant species suitable for combustion. Over a period of 6 year, yield, energy gain, and environmentally relevant substances in the plant and the soil were determined under practical conditions. Fertilization was carried out in four variants each ranging from 0 to 150 kg N ha -1 and with wood- and straw ashes, as well as basic mineral fertilizer. Plant protection products were entirely dispensed with. The results show that, except for Topinambur haulm (Jerusalem artichoke) and short rotation coppice with undersown crops, the mean yield ranges between 8 and 12 tDM h a ~ and that a reduction of nitrogen application from 150 to 75 kg N ha i causes only slight yield losses. Without fertilization, yields diminish by 20-40% after 6 years, except for poplars, which reach similarly a high yield level as with fertilization. The contents of the emission- and combustion-relevant plant nutrients, such as nitrogen, potassium, sulfur and chlorine, are significantly lower in poplars and willows than in grass, rye, triticale and hemp. Heavy metals, such as cadmium, copper, zinc, and lead, are absorbed differently. Hemp, poplars, and winter rye allow high-energy yields to be achieved. Even if nitrogen fertilization is reduced, net energy gains of more than 120 GJ ha i year i (3.2 kl oil equivalent ha year -t ) are reached.
03/00245 The potential contribution of renewable energy in air pollution abatement in China and India Boudri, J. C. et al. Energy Policy, 2002, 30, (5), 409-424. The potential for the use of renewable sources of energy in China and India and their cost effectiveness in air pollution abatement in Asia is studied. This is done through an integrated assessment of the costs and the environmental impacts of several types of renewables, in comparison with fossil fuels. Results for different scenarios for fuel use in China and India for the period 1990-2020 are presented. The acidification model R A I N S - A S I A is used to analyse environmental impacts (exceedance of critical loads for acidification) and to perform an optimization analysis, aiming at minimizing abatement costs. The costs of controlling the emissions from fossil fuels (e.g. through flue gas desulfurization). For the environmental targets analysed in this study an increased use of renewable energy could cut SO2 emission-control costs in China by 17-35%, and in India by more than two thirds.
03/00246 Wave energy in Europe: current status and perspectives Cl~.ment, A. et al. Renewable and Sustainable Energy Revien's, 2002, 6, (5), 405-431. The progress in wave energy conversion in Europe during the past ten years is reviewed and current activities and initiatives in the wave energy sector at National and Union level are described. Other
important activities worldwide are summarized. The technical and economical status in wave energy conversion is outlined and important wave energy developments are presented.
08
STEAM RAISING Boiler operation/design
03•00247 Combined cycle plant efficiency increase based on the optimization of the heat recovery steam generator operating parameters Franco, A. and Russo, A. International Journal qf Thermal Sciences, 2002, 41, (9), 843-859. Combined cycle (CC) power plants allow the growing energy demand to be met with the least fuel consumption. Thus it is of great interest to define a strategy for the optimization of these systems, in order to get greater performances and efficiency from them. The objective of most manufacturers would be to reach an overall thermal efficiency of 60% in the short-term period, by improving the gas turbine inlet temperature. In this paper, it is shown how it could be possible to reach the same performances by best fitting the existing technology. In particular attention is directed to the optimization of the heat recovery steam generator (HRSG), as a first step in the analysis of the whole plant, according to a hierarchical strategy. The problem is handled by adopting both a thermodynamic and a thermoeconomic objective function instead that with the usual pinch point method. Thermodynamic optimization has the purpose to diminish energy losses, expressed on exergy basis, while the aim of the thermoeconomic optimization is the minimization of a cost function, sum of the cost of exergy inefficiencies and the cost of the HRSG. Proposed methods have been applied to some HRSG configurations, including some present commercial plants. The results of the application of the thermoeconomic optimization leads to a meaningful increase of the thermal efficiency of the plant that approaches the 60%, obtained with and increases of the heat surface and a decrease of the pinch-points. The economic evaluations are referred to US dollars ($) even if the costs are referred to European scenario, assuming US$1 = El.1.
03/00248 Computer simulation and visualization of the thermodynamic properties of steam and steam processes Barakat, M. H. Energy Sources, 2002, 24, (33, 247-261. Process simulation programs based on water and steam as a working fluid require the feed of thermodynamic properties during the program runtime. This paper presents the mathematical model necessary to identify the phase and to simulate the thermodynamic properties of water, steam, and wet steam at different temperatures and pressures. The simulated values are compared to the tabulated values and the deviation errors are indicated. A computer program is constructed and visual presentation of the properties on an interactive interface, as well as by plotting on the enthalpy-entropy chart, are presented.
03100249 High temperature air combustion boiler for low BTU gas Kawai, K. el al. Energy Conversion and Management, 2002, 43, (9-12), 1563-1570. A new concept boiler where fuel can be efficiently combusted by high temperature preheated air is proposed and experimental demonstration is done. This boiler is suitable for low BTU gas derived from gasification process of coal and wastes with no dioxin emission. This boiler is characterized by the following features: uniform heat flux field, augmentation of heat transfer, reduction of combustion noise level, suppression of NO, emission and compactness. Preliminary experiments using natural gas as a fuel demonstrate above distinct performance as well as good agreement with three-dimensional numerical simulation.
03/00250 Methods of choosing the optimal parameters for solid fuel combustion in stoker-fired boilers Rusinowski, H. et al. Energy Conversion and Management, 2002, 43, (9123, 1363-1375. Stoker-fired boilers are used for the combustion of coal and solid wastes. The most important disadvantage is their low thermal efficiency. The authors present methods of choosing the optimal rate of travel of the grid and height of the fuel layer basing on both real scale and laboratory measurements. Basing on industrial-scale experiments the authors calculated the optimal thermal efficiency and main
Fuel and Energy Abstracts January 2003 31