[en] Photovoltaic power plants are necessary to reduce the cost of solar energy but they require large areas to spread on their panels (1 MW requires 1 ha) and might be source of conflict with other land users like farmers. Areas dedicated to photovoltaic plants must be part of the national development scheme and must include ancient industrial sites that have no-future (for at least the next 15 years) like mines, dumps or waste lands. The examples of an ancient uranium mine and a municipal dump turned into a solar farm are presented. This kind of consensus could be the right solution that pleases both land owners and land developers without disturbing agriculture development. (A.C.)

[en] Here an estimate of the effect of random fluctuations in the solar radiation on the expected standard deviation of the performance of photovoltaic systems is presented. (author)

[en] This paper presents an approach for modeling space solar power system architectures, integrating both economic and technical parameters for all space and ground-based system elements. Key elements of the approach are an integrated architecture assessment model that is used to conduct architectural analysis, a data dictionary that defines all technical and economic parameters, and detailed analyses that are conducted to external to the integrated model for specific architectural elements. The overall architecture of the space solar power system is composed of eight specific elements including both ground and space segments. Key parameters are identified for each element including variables that are input by the user as well as dependent variables that are calculated by the model. For each element, parameters are grouped into four categories including engineering and operations related technical parameters, and recurring and non-recurring cost parameters. The integrated model allows the user to gain insights into the viability of the entire space solar power system through outputs such as internal rate of return, net present value, average duty cycle for use of on-orbit assets, and total non-recurring investment cost. The user can also conduct sensitivity analysis to understand those technologies that have the greatest impact, the markets that provide the greatest opportunity, and the systems which offer the greatest potential

[en] Short communication

[en] Short communication

[en] Studies of systems to provide solar power from space for terrestrial use defined very large, geostationary Earth orbit (GEO) satellite concepts that--given massive initial government investments and extremely low cost space launch--might have led to power production at costs only somewhat higher than expected commercial prices. These studies of space solar power (SSP) succeeded in establishing technical feasibility. Shortly after the completion of the 1970s study, however, US funding came to an abrupt and seemingly permanent halt--in part because projected costs for the reference system were staggering: well in excess of $100B to achieve the first commercial kilowatt-hour of power. SSP has seen sporadic study and limited experimentation during the past decade (e.g., in Japan). Still, no existing SSP concept has engendered private development. New technologies now make possible concepts and approaches that suggest that SSP economic feasibility may be achievable early in the next century. In 1995, NASA's Advanced Concepts Office initiated a study taking a fresh look at innovative concepts for SSP that differ markedly from previously examined concepts, addressing innovative system architectures, markets and technologies that could radically reduce initial and operational costs. This paper will explore the issues associated with SSP and will summarize the results to date of NASA's recent fresh look at this important and increasingly timely field of space applications

[en] Thousands of small photovoltaic power stations are demanding their connection to the national power grid. ERDF, the manager of the grid, has to adapt and reinforce some lines. The connection costs that were previously supported by the consumers has to be paid by the demander as the law NOME stipulates it. For installations below 18 kVA the cost ranges from 800 to 1600 euros and for more powerful installations an estimate has to be drawn by ERDF and the cost will depends on the presence or not of an adequate transformer in the vicinity, on the possible upgrading of the transformer, on the length of the cables necessary to make the connection and on whether the installation is in an urban area or not. A table gives the ERDF tariffs for the connection and the case of the connection of a 35 kVA station built on the roof of a shed in a rural zone is dealt with. The procedure to follow for demanding the connection to ERDF is detailed. (A.C.)

[en] A study was conducted to project photovoltaic (PV) module characteristics for the 1995 timeframe, and conceptual designs and cost estimates were developed for four 50-MW PV plants. Design performances were modelled for the conditions at two sites in California and Florida. Hypothetical but realistic utilities were formulated for each site for the purpose of assessing the economics of the PV plants. The capacity value and production cost analysis were used in an overall economic assessment of the PV plant designs. Environmental externalities associated with the displacement of hydrocarbon fuels were taken into account. Other factors considered included the year of installation of the technology and the module production volume. Sites with the highest insolation were found to be able to support economically viable projects in the near future if investors can receive credit for project environmental benefits and overall PV demand can support a 25 MW/y production facility. Between 65% and 75% of the total benefits of the designs studied were associated with energy displacement, so future economics will be highly sensitive to future fossil fuel costs. Air quality benefits amounted to 18-25% of total project benefits and capacity benefits were 4-10%. 3 refs., 2 figs., 9 tabs

[en] The aim of this paper is to introduce a system developed for monitoring PV solar plants using a novel procedure based on virtual instrumentation. The measurements and processing of the data are made using high precision I/O modular field point (FP) devices as hardware, a data acquisition card as software and the package of graphic programming, LabVIEW. The system is able to store and display both the collected data of the environmental variables and the PV plant electrical output parameters, including the plant I-V curve. A relevant aspect of this work is the development of a unit that allows automatic measuring of the solar plant I-V curve using a car battery as power supply. The system has been in operation during the last two years and all its units have functioned well

[en] Short communication