07 Alternative
energy sources (solar energy)
from the southern reservoir. The separated water will be reinjected into the northernmost part of the northern reservoir, in order to prevent a cold sweep problem for production.
ohmic, the I-C’characteristics of several other device\ acre Invcstlaated. It has beendiscovered that the presence of Cc,,, in a bulk heterojunct&n solar cell introduces fill factor reducing shunting paths.
Structure and hydrology of the Ogiri field, West Kirishima geothermal area, Kyushu, Japan
00101982 Crystal network formation in organic solar cells Dittmer, J. J. Sol. .Ger,qrMar. & Sol. C<,l/s.2000. 61. (I ). 53-61
00101976
Goko. K. Georhcrtnic.\, 2000. 29. (2). 127-149. The geothermal system in the West Kirishima area is controlled by a system of faults and fractures oriented along two main directions. northwest to southeast and east-northeast to west-southwest. The Ginyu fault extends through the Ogiri field in the Ginyu area, which is one of the east-northeast to west-southwest striking faults in this area. This fault is the reservoir target for developing the geothermal resources in the Ogiri field. The Ginyu fault is a near planar fracture with a uniform temperature of 232°C and has near-neutral pH, chloride fluids. Based on the results of a detailed analysis of the Ginyu faU\t, all production wells drilled in the Ogiri field intersected the Ginyu fault reservoir successfully, securing steam production for a 30 MW, power plant. A typical fracture-type geothermal model for the Ogiri field was developed on the basis of the geology, electric and geophysical logs. fluid chemistry, and well test data.
00101977 Takigami geothermal system, northeastern Kyushu, Japan
Furuya. S. Georher~m,.\. 2000. 29. (2). 191-21 I The Takigami geothermal reservoir is bounded by a system of faults and fractures oriented along two main directions, north to south and east to west. The Noine fault has a large vertical displacement and trends north to south, dividing the subsurface characteristics of resistivity. permeability, temperature and reservoir depth. The Takigami geothermal fluid has a near neutral pH and is of the Na-Cl type, with a chloride content ranging from 400 to 600 ppm. The southwestern part of the area has the highest subsurface temperature, up to 250°C. The deep fluid originates from the southwest, and flow is mainly to the north and partly to the east along faults and fractures, decreasing in temperature with increasing lateral flow.
00/01976 Thermal and geochemical structure of the Uenotai geothermal system, Japan Takeno, N. Gcorhcrr~f~r~s. 2000, 29. (2). 257-277. The Uenotai geothermal area is located in southern Akita prefecture of northern Honshu Island. The Uenotai geothermal system is a liquiddominated system with a central zone of aquifer boiling. The two-phase reservoir has evolved from liquid in the natural state due to exploitation. Gas composition of the vapor phase in the reservoir is nearly in equilibrium and correlates with the vapor fraction in the reservoir and with discharging steam quality. The marginal part of the Uenotai system has cooled with the drop in ground-water level. The chemical characteristics of the geothermal water indicate mixing of the immature high chlorine source water with conductively heated or steam-heated shallow water or surface water, as well as boiling and steam gain.
Solar energy
00101979 A comparative life cycle energy cost analysis of photovoltaic and fuel generator for load shedding application Koner, P. K. Sol. OI?,:~.I Mrrf. & Sol. Cells, 2000. 60. (4). 309-322. Comparative life cycle energy cost analysis for different electricity generators (photovoltaic generator, kerosene generator and diesel generator) used during load shedding is presented. The parameters considered for calculation of the unit cost of energy are: the discount rate, inflation rate, IREDA loan facility to promote PV, operation and maintenance cost of PV and fuel generator (FG) set and the associated fuel cost. It is found that the unit cost of PV electricity is comparable to or less than that of FG generated electricity at present market prices.
00/01960 A photoelectrochemical solar cell based on ZnOldyel polypyrrole film electrode as photoanode Hao, Y. Sol. Elto,g~, Mtrr. & Sol. Crlls. 2000. 60. (4), 349-359. Nanostructured zinc oxide film electrodes were prepared. A preliminary PEC solar cell based on nanostructured Zno/dye/polypyrrole (PPy) film electrode was fabricated. A fill factor of 0.754 and a high overall light to electricity conversion efficiency of 1.3% for this PEC solar cell were obtained. The sensitization mechanisms of the nanostructured zinc oxide electrodes were also discussed.
This paper presents a study on the effects of annealing on performance and morphology of photovoltaic devices using blends of two organic semiconductors: a conjugated polymer and a soluble perylene derivative. The efficiency of such photovoltaic cells has been determined. The effect of temperature on blend morphology has been investigated for actual device films. Annealing leads to the formation of micron size perylene crystals and an enhancement of the quantum efficiency. This enhancement has been attributed to the formation of an electron conducting perylene crystal network.
00/01983 Dye-based donor/acceptor solar cells Petritsch,K. Sol. D1erx.r Mar. & Sol. C&. 2000. 6 I. (I ).
63-72. Organic donor/acceptor solar cells have been fabricated with three different architectures using solrrhle derivatives (dyes) of the molecular semiconductors phthalocyanine as electron donor (D). i.e. hole transport mate!-ial and perylene as electron acceptor (A). i.e. electron transport material. The\? architectures comprise a blend and a double layer structure as well ;I\ the only recently reported laminated-device structure. The orpanIc \rmiconductlng films were deposited at room ICI~I/>P~~/~II~~~,a spin coating from solution. Current-voltage (I-I’) characterlsticc and erternal ~ILIII~UI~ efficiency spectra will he discussed. The measured quantum efflclenclr\ reach values between 0.3% and 1.1% with a photorcsponhc coverIng the entire spectrum of visible light. The results demon\tratc that together with insoluble small molecules (pigments) and conJugated polymerr. dye molecules represent a new class of organic semi-conducting materials that can be used to manufacture D/A solar cells.
00101984 Effect of short-wavelength radiation on the photoresponse of MIS-IL solar cells (experimental study) Kagilik,A. S. and Abusaid, M. F. Applictl Ewr,q~.. 2000. 65. (l-4). I I5
120. MIS-IL solar cells are potentially low-cost devices, due to their simplicity and avoidance of the high-temperatures in their fabrication processing. In addition, inversion-layer (IL) solar cells are demonstrated to have higher collection efficiencies at short wavelengths. The spectral response of MISIL solar cells has been measured in the wavelength range 340-I 100 nm. From these measurements, the external and internal quantum cfficiencles have been determined. Also, a comparative study of the quantum efficiencies of inversion layer and diffused junction cells has been carried out. The IL cell has a higher collection-efficiency for carriers generated by ultra-violet light than the conventional p-rt junction solar cell. These result\ reveal one of the important advantages of IL solar cells. Also. it can he seen that IL solar cells can be improved by surface texturing in a slmllal- way to ;I conventional diffused solar cells.
00101985 Effects of sandblasting on the efficiencies of solar panels Bouaouadja,N. App/id Etwrg~~ 2000. 65. (l-41.99 105. Photovoltaic solar-energy can be a solution. if efficiently used. for providing electrification, water pumping and communications in inaccessible region\ as in the south of Algeria. The glass-protected solar panels made for thecc purposes are, however, constantly exposed to the damaging effects caused by sandstorms. These occur particularly in spring with velocities that can reach 120 km/h, and for various durations, typically -48 h. The small particles of sand (of average size > 120 /Im‘l rise high into the atmosphere. and the relatively large particles (average size > 120 irm) remain at lower altitudes and at ground level. This preliminary work considers the effects of the sandblasting duration on the efficiencies of solar panels. The result\ show that the solar panels’ efficiencies decrease during sandstorms. and some of these decreases are permanent when the protective glass sheets arc damaged by erosion.
00101986 Effects of temperature and r.f. power sputtering on electrical and optical properties of SnO, Hamzaoui. S. and Adnane. M. Applied EWV,~IL NOO. 65. ( I 4). 1’1 2X. Electrical and optical properties of SnO,. which ic a photovoltaic material for solar energy conversion fo electricity. have been invcstlgated. Semconducting Sn02 has been grown by r.f. sputtering. Reported in this paper are the influence of process variables, such as substrate temperature andr.f. power. The film resistivity decreases with increasing temperature. but rises with increasing r.f. power: these can be related to crystallite size and the film orientation respectively. From the optical measurements, we deduce a variation of band-gap energy with substrate temperature. We show that the substrate temperature has a subsequent influence on the electrical and optical properties of this material.
00101981 Analytical study of PPV-oligomer-and &-based devices for optimising organic solar cells
00/01987
Geens, W. So/. E~rrr,~~, Mrlt. & Sol. Cell,. 2000. 61. (I ). 43-5 I. A blend of a S-ring !I-octyloxy-rubstltuted oligo(p-pbenylene vinylene) and C,,,,. sandwiched between two electrodes. has been used as the active layer for an orgamc solar cell. It delivered external quantum efficiencies up lo 60% in the visible and 70% in the UV part of the spectrum. To unambiguously determine which parts of the bulk heterojunction structure are responsible for the rectifying behaviour and which can be considered as
Miller, D. and Hope, C. E,rc,rg~. Po//t,r. 2000. 2X. (2). X7 I05 The World Bank has sought to advance the diffusion of solar photovf)ltalc (PV) technology for off-grid applications in the developing world. As these systems are fundamentally different to centralised power stations and conventional rural electrification, the World Bank has been learning how
Learning to lend for off-griq solar power: policy. :a,s,skoans from World Bank loans to India, Indonesia, and Sn
Fuel and Energy Abstracts
July
2000
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