Development and Prototype Testing of Low-Cost Lightweight Thin Film Solar Concentrator

Author(s):  
Gani Ganapathi ◽  
Arthur Palisoc ◽  
Armin Buchroithner ◽  
Sai Nataraj ◽  
Bill Nesmith ◽  
...  

A low-cost rigid foam-based concentrator technology development program was funded by the DOE SunShot Initiative to meet installed cost goals of $75/m2 vs. current costs of ∼ $200–250/m2. Phase 1 of the project focused on design trades and cost analyses leading to a cost-optimized self-powered autonomous tracking heliostat concept with a mirror surface area in the 100m2 range. In Phase 2 30-year accelerated testing of the mirror modules based on ReflecTec film with 94% specular reflectivity bonded on composite foam substrate were initiated and completed in Phase 3. The tests with 15 coupons showed optical performance degradation of less than 5% in specular reflectance following 30-year equivalent UV testing and other abuse testing such as acid rain, bird dropping, thermal cycling, etc. A small scale prototype (3m×2m) heliostat design based on modular truss elements with removable mirror modules was developed in detail. In this phase components such as the dual-axis actuators were sized and selected based on wind load requirements and pointing accuracy demands were completed. Finite Element analyses for the mechanical structure with mirror modules were performed using three separate commercial codes — ANSYS, COMSOL and SolidWorks to validate the optical errors induced by wind loads on the structure up to 35 mph. Results indicated that the RMS deflections contributed to less than 0.4 mrad pointing error. Dynamic response of the heliostat indicated that the first 5 eigenmodes were in the 17–20 Hz range. The individual structure elements such as the trusses and c-rails were fabricated locally and assembled with the mirror facets in the lab for initial fit check and testing. The nine mirror facet surface errors were characterized using photogrammetry and verified using Reverse Hartmann techniques and showed to be in the order of 1 mrad or less. A three-level controller (main, gateway and heliostat) was architected and built. Tracking of the sun is done using NREL’s Sun Tracking Algorithm implemented in the gateway controller. Target-pointing vectors are calculated for each heliostat and conveyed wirelessly to the individual heliostat controllers for actuating the azimuth and elevation motors. The power subsystem consisting of solar panels and a battery provide 24V for the actuators and controller boards. The system was sized to provide adequate power for a period of 5hrs of operation when power is not available. Initial calibration will be performed with on-site camera tracking the sun’s image on a target located approximately 52m from the heliostat. Testing of the heliostat pointing under calm and windy conditions will be done to demonstrate overall performance that meet DOE targets of 4 mrad under 27mph winds. Commercialization efforts are underway to transition the design to the commercial sector. The project is well on its way to approaching overall cost targets and current estimates are approximately $90–110/m2 and lower costs can be achieved with alternates to the film we have identified.

Author(s):  
Gani B. Ganapathi ◽  
Art Palisoc ◽  
Bill Nesmith ◽  
Gyula Greschik ◽  
Koorosh Gidanian ◽  
...  

A low-cost rigid foam-based concentrator technology development program was funded by the DOE SunShot Initiative to meet installed cost goals of $75/m2 vs. current costs of $200–250/m2. The cost reduction in this approach focuses primarily on designing a mirror module with a rigid foam center with stainless steel facesheets and reflective film. The low mechanical strength of the foam is compensated by optimizing the densities and dimensions to meet pointing accuracy requirements of 4 milliradians (mrad) in 27mph winds. Two alpha concentrators were built to validate the mirror module manufacturing process and one of them was accurate to 0.15 mrad RMS vs. the design requirement of 1 mrad RMS. To understand the lifetime reliability of the panels, fifteen 4-inch square samples were exposed to various environmental conditions including acid rain, bird droppings, thermal cycling, and the final results indicated no loss in reflectivity of 95%. UV testing will be performed in the next phase. Three mechanical structure options covering the range of large multi-faceted heliostats with diagonal load carrying elements, small single facet heliostats low to the ground and optimized truss-based deep structure designs were analyzed with FEA and analytically; results indicated a significant cost benefit (>2×) for the truss-based design over the other options. Other elements such as the controls, actuators were also considered in th analysis with vendor data. Cost trades were performed for heliostats ranging from 10m2 to 250m2. The results indicated a broad installed cost minimum around $113/m2 for heliostat sizes ranging from 80 m2 to 130 m2. Additional cost saving approaches will be considered in Phase 2 of the project.


1979 ◽  
Author(s):  
M. W. Horner ◽  
W. H. Day ◽  
D. P. Smith ◽  
A. Cohn

A continuing technology development program initiated by General Electric (GE) in the early 1960s and joined by the Electric Power Research Institute (EPRI) in 1974 is successfully resolving potential barrier problems in the development of water cooled turbines. Early work by GE Corporate Research and Development demonstrated the feasibility of closed circuit, pressurized water-cooling of stationary nozzles (vanes), and of open circuit, unpressurized water-cooling of rotating buckets (blades). A small-scale turbine was designed, fabricated, and operated at a gas temperature of 2850 F (1565 C) at 16 atm, with surface metal temperatures less than 1000 F (540 C). Early results from the EPRI sponsored Water-Cooled Gas Turbine Development Programs were presented at the 1978 Gas Turbine Conference (Report #ASME 78-GT-72). This paper reports more recent results, obtained between mid-1977 and mid-1978. Significant progress has been made in a number of areas: (a) water-cooled nozzle and bucket design and fabrication, (b) corrosion kinetics model verification and testing, (c) partially filled internal channel bucket heat transfer testing, and (d) stationary to rotating water transfer and collection testing. Results to date are encouraging with regard to the application of water-cooled turbine components to achieve improved reliability and fuels flexibility at increased turbine firing temperatures.


2020 ◽  
Author(s):  
Florencia López Boo ◽  
Jane Leer ◽  
Akito Kamei

Expanding small-scale interventions without lowering quality and attenuating impact is a critical policy challenge. Community monitoring overs a low-cost quality assurance mechanism by making service providers account-able to local citizens, rather than distant administrators. This paper provides experimental evidence from a home visit parenting program implemented at scale by the Nicaraguan government, with two types of monitoring: (a) institutional monitoring; and (b) community monitoring. We find d a positive intent-to-treat effect on child development, but only among groups randomly assigned to community monitoring. Our findings show promise for the use of community monitoring to ensure quality in large-scale government-run social programs.


1980 ◽  
Vol 209 (1174) ◽  
pp. 183-186 ◽  

Crystal ball gazing is a hazardous occupation: the sharper the picture, the greater the possibility of error. In the future, appropriate technologies that will raise standards of health and diminish the prevalence of disease in the Third World must take cognizance of such factors as burgeoning population growth, impossibly high cost of energy sources, a widening gap between food requirements and food production, increasing urbanization, and inherent difficulties of control of disease vectors and water-borne diseases. The technologies that must be made available will be both large-scale and small-scale, low-cost and simple, improving life for the individual and the community, mediated by appropriately trained and adequately supervised polycompetent auxiliaries. The present reappraisal of health needs in the context of food (seeds, soils, irrigation, protection against loss of the harvested products) and of prevention of disease by appropriate prophylactic measures and its treatment, will necessitate hard thinking and greater cooperation between all concerned.


1978 ◽  
Author(s):  
M. W. Horner ◽  
W. H. Day ◽  
D. P. Smith ◽  
A. Cohn

Development of water-cooled gas turbine technology was begun at General Electric in the early 1960’s, and by the early 1970’s, a small-scale turbine had been operated to temperatures of 2850 F and 16 atm, with metal temperature less than 1000 F. The Water-Cooled Turbine Development Program was begun in 1974, funded by the Electric Power Research Institute, to do preliminary design on a utility-size gas turbine using water cooling and to do basic technology development to address the problem areas. This paper presents the results of the program, including descriptions of the test hardware and data on phenomena, such as corrosion, erosion, heat transfer, and water collection. Cycle analysis results are presented for two potential combined cycle configurations: (a) one using low-Btu coal gas fuel, and (b) one using a heavy liquid fuel. Summary performance curves are given showing the effect of changes of pressure ratio and firing temperature. Methods of improving the baseline cycle and their effect on baseline performance which are judged most promising are also given on the performance curves. Turbine design features to achieve low component metal surface temperatures for increased fuels flexibility are given with particular emphasis to the first-stage nozzles and buckets. Fundamental development testing needs have been identified and programs have been put into place to bring the water-cooled turbine to a point where a full-size water-cooled turbine can be built. Descriptions of the development test facilities, task descriptions, test plans and /or test results are given for eight tasks.


foresight ◽  
2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Reza Hafezi ◽  
Ahmad Borumand Kakhki ◽  
Maziar Attari ◽  
Zohreh Besharati Rad ◽  
Ashraf Sadat Pasandideh

Purpose Many devices needed electrical power to work, thus, major energy carriers such as oil and gas were used to generate electrical power via converter mechanisms and special technologies. The microturbine is a developed technology that is remarkable for its relatively high performance and ability to use several types of fuels. Microturbines are economically feasible because of the production of combined heat and power and small-scale applicability. This study aims to investigate microturbine technology development to support modern energy access in a developing country (i.e. Iran). Design/methodology/approach This paper presents a technology foresight methodology to create plausible futures of microturbine development in Iran when the country faces different driving forces and uncertainties. On other hand, the paper deals with a theoretical question: how to select appropriate foresight methodology? A procedure is proposed, which equipped the research team to select appropriate method combinations based on Popper’s diamond. Finally, the selected methodology includes defining focal issues environmental scanning and patent analysis aimed at developing five plausible scenarios for microturbine development future in Iran and creating shared visions among policymakers. Findings This paper proposed a series of scenarios on the path to developing microturbine technology. The scenario development logic in a participatory way contains a common four-quarter technique that attempts to depict scenarios based on two critical uncertainties inclusive energy price and technology obsolescence, which will shape the future. Also, a scenario is presented to describe a wild card that can disturb the desired futures. Such materials help decision-makers to policies under plausible conditions that guarantee a robust policy basket. Originality/value The originality of this paper can be studied based on two aspects, first, the methodology that provides a systematic method selections procedure in an emerging complex technology development program. Second, from the practical aspect, this paper is one of the very first attempts to manage the microturbine technology development program. Then, results are used to feed the policy-making process in Iran.


1993 ◽  
Vol 28 (10) ◽  
pp. 1-8 ◽  
Author(s):  
A. Gaber ◽  
M. Antill ◽  
W. Kimball ◽  
R. Abdel Wahab

The implementation of urban village wastewater treatment plants in developing countries has historically been primarily a function of appropriate technology choice and deciding which of the many needy communities should receive the available funding and priority attention. Usually this process is driven by an outside funding agency who views the planning, design, and construction steps as relatively insignificant milestones in the overall effort required to quickly better a community's sanitary drainage problems. With the exception of very small scale type sanitation projects which have relatively simple replication steps, the development emphasis tends to be on the final treatment plant product with little or no attention specifically focused on community participation and institutionalizing national and local policies and procedures needed for future locally sponsored facilities replication. In contrast to this, the Government of Egypt (GOE) enacted a fresh approach through a Local Development Program with the United States AID program. An overview is presented of the guiding principals of the program which produced the first 24 working wastewater systems including gravity sewers, sewage pumping stations and wastewater treatment plants which were designed and constructed by local entities in Egypt. The wastewater projects cover five different treatment technologies implemented in both delta and desert regions.


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