[en] The traditional renewable energy resources such as firewood, charcoal, crop residues (wastes) and animal dung, account for virtually all of the fuel used in many rural areas, and may account for about 20 to 25 per cent of the total energy consumption in the developing world. But this sources of energy posses a clear danger in the living of much of the population of the rural areas and increases the air pollution. About 75 of the population of the rural areas in the developing countries uses traditional fuels, largely within household and primary for cooking. 15 figs

[en] In spite of the fact that solar energy is a ''clean'' energy form, gaseous pollutants are emitted during the manufacturing of the systems necessary for its utilisation. An attempt is made in this paper to estimate the level of atmospheric pollutants emitted during the successive stages which make up the manufacture process for solar water heating (SWH) systems, and to evaluate these results in comparison with the respective pollutant emission levels attributed to the generation of electricity in Greece's conventional power plants. As energy consumption is recognised as the main source of atmospheric pollution, a Life Cycle Analysis (LCA) method was applied, focusing on the most energy-consuming stages of the SWH system production process. The conclusions of the analysis indicate that the emissions of gaseous pollutants associated with the utilisation of solar energy are considerably lower than those caused by the production of electricity in conventional systems, thereby substantiating that solar energy utilisation can make a notable contribution to the abatement of atmospheric pollution. (author)

[en] Production of electricity in solar cells enables a flowing energy resource, sunlight, to be brought into the technological system. Although only small adverse environmental effects result from the operation of solar cells, production and sometimes disposal have more environmental impact. The impact is described for a number of types of solar cells, in various applications, and the technology is evaluated from an environmental point of view, as compared with power production from fossil fuels and nuclear power. A life-cycle perspective is adopted, although the study is not a quantitative life-cycle assessment. Crystalline silicon (c-Si) and amorphous silicon (a-Si) cells, copper-indium-diselenide (CIS) and cadmium-telluride (CdTe) cells, are considered. c-Si cells require considerable amounts of energy during production. Both CIS and CdTe cells contain cadmium, but CIS to a smaller extent. Indium is a very scarce resource. All the technologies except CdTe involve use of toxic and/or explosive gases during production. Solar cells are used in consumer products such as pocket calculators. The energy production in this application is marginal. They may constitute an environmental problem if they contain cadmium or are used in connection with cadmium containing batteries. Stand-alone systems often require batteries which contain heavy metals. They may contribute to electivity generation to some extent. They may have a positive influence on aesthetic natural values through reducing the need for power transfer to single, remote power consumers. Large scale electricity production in grid-connected systems is possible in a longer time perspective, and thus the assessment has a larger degree of uncertainty. (author)

[en] This paper discusses the present state and the future potential of solar thermal and photovoltaic (PV) technologies, and examines both the environmental implications of these technologies and the economics which determine their viability in the energy market. Although some significant cost reductions have been achieved, particularly in PV technology, solar conversion technologies are still not generally competitive against conventional fuels, and future cost reductions may be limited. It is argued that fiscal measures will be necessary if solar conversion technologies are to make a significant global impact. (Author)

[en] A Life Cycle Assessment (LCA) is a tool for analysing and estimating the total influence on the environment during the complete life cycle of a certain product. The assessment can bring valuable information about the production processes, the use of materials, the use and the disposal of the product. This information can be used to determine, how to improve the product environmentally. The LCA information can also be used as a comparative study to determine which of two products are environmentally preferably. LCA''s on solar collectors are interesting because solar energy systems are introduced to encourage a sustainable development, hence it follows that the systems themselves should be based on a sustainable technology. The collector should produce as much energy as possible during its lifetime, but it is also important that it is produced in an environmentally friendly way, that it can be disposed properly after use and so on. (orig.) 2 refs

[en] This paper creates a theoretical framework of analysis for understanding the concerns and methods of ecological designers. Various definitions of ecological design are reviewed to show its basis in natural ecological systems, either as analog or as context, and its purpose as creating sustainability. Ecological design methods are categorized as conceptual, factual, or integrative. The characteristics and definitions of these methods are explained and several practitioners and theorists classified. Lyle's concept of ecosystematic order is used to show the basis of methods in either a building architecture or a landscape architecture perspective. A matrix is generated and applied to a representative of each category, showing the concerns of each in terms of the integration of human and natural ecosystem structure, function, and location

[en] In global terms, communities can be open-quotes readclose quotes as tissues on the land. In both their placement and physical form, they demonstrate varying degrees of environmental fit. They can work with and support, or conquer and degrade the natural environment. Energy resources in their acquisition, delivery and conversion play an insidious but fundamental role in this linkage. CAD-based modeling offers a powerful tool for interpreting the role of energy resource in community patterning/community form -- the open-quote tissuing of the landclose quotes. When linked to database capability (e.g. GIS), the very opportunity for open-quote designing environmental impactclose quotes is possible. This paper presents CAD-based models which examine the organizational impact of energy resources and environmental forces as prime determinants in community form. Included is a discussion of global and local determinants. As a rule, the community models presented attempt to consider tissuing of the land as a transparent/interactive condition. That is, the layering of the community is structured to interpret and express opportunities for the design of earth/sky connection through, the community fabric. The plan/footprint patterning reflects consideration of orientation and encompasses reference to infrastructure options for tissue support. Extensive descriptive, and experiential, images will be provided during presentation of the paper to support the written explanation of the models examined

[en] The authors describe the concept of the central receiver and consider the following topics: the plan of their solar thermal power system or ''solar power tower'' based on optical transmission; the history of the solar tower; the receiver subsystem; the design of the heliostats and their placement in a field; thermal storage; environmental concerns; and economics

[en] This study is part of the ExternE program of the European Commission on the external costs of the photovoltaic (PV) fuel cycle. The objective of this paper is the quantitative evaluation of the main environmental impacts of two selected PV systems--the ground-based 1MWp system in Toledo, Spain and the 40 kWp building integrated facade in Newcastle upon Tyne, NE England, using the methodology of life cycle analysis (LCA). Both systems use silicon wafer technology at present, but the Newcastle facade was also studied with the incorporation CdTe modules. The results of the LCA show that atmospheric emissions are the priority impacts with respect to the assessed PV systems. Comparing Si wafer systems, the CO₂ emissions were 88 t/GWh for the Toledo PV plant and 143t/GWh for the BIPV facade. If the facade had used electrodeposited CdTe, the CO₂ emissions would fall to about 50t/GWh

[en] During normal operation, photovoltaic (PV) power systems do not emit substances that may threaten human health or the environment. In fact, through the savings in conventional electricity production they can lead to significant emission reductions. There are, however, several indirect environmental impacts related to PV power systems that require further consideration. The production of present generation PV power systems is relatively energy intensive, involves the use of large quantities of bulk materials and (smaller) quantities of substances that are scarce and/or toxic. During operation, damaged modules or a fire may lead to the release of hazardous substances. Finally, at the end of their useful life time PV power systems have to be decommissioned, and resulting waste flows have to be managed. An expert workshop was held as part of the International Energy Agency Photovoltaic Power Systems Implementing Agreement Programme, to address these environmental aspects of PV power systems. The objectives of the workshop were: (a) review/overview of issues and approaches regarding environmental aspects of PV power systems; (b) enhanced clarity and consensus regarding e.g. Energy Pay-Back Time; (c) identification of issues of environmental importance regarding PV power systems ('hot spots'); (d) identification of issues requiring further attention ('white spots'); and (e) establish a network of researchers working on PV environmental issues. 25 participants from Europe, the United States, Japan, and Australia attended the workshop, representing the researchers in the field of environmental aspects of PV systems, R ampersand D managers, industry and utilities. The environmental issues that are considered most relevant for PV power systems were identified in the workshop as well as the approaches that may be used to investigate them. The main environmental issues discussed at the workshop were: energy use; resource depletion (e.g. the resource availability for indium (used in CIS- modules) and silver (used in mc-Si modules) has been indicated as potentially problematic); climate change (reenhouse gas emissions (notably CO2) mostly originate from energy use and the potential for PV power systems to reduce these emissions is receiving increasing attention); health and safety (continuous or accidental releases of hazardous materials can pose a risk towards workers and the public); waste; and land use (at least in the case of ground-based arrays). 15 papers are presented in this report