215 research outputs found
The CPV âtoolboxâ: New approaches to maximizing solar resource utilization with application-oriented concentrator photovoltaics
As the scaling of silicon PV cells and module manufacturing has driven solar energy
penetration up and costs down, concentrator photovoltaic technologies, originally conceived as a
cost-saving measure, have largely been left behind. The loss of market share by CPV is being locked in
even as solar energy development encounters significant obstacles related to space constraints in many
parts of the world. The inherently higher collection efficiency enabled by the use of concentrators
could substantially alleviate these challenges, but the revival of CPV for this purpose requires
substantial reinvention of the technology to actually capture the theoretically possible efficiency gains,
and to do so at market-friendly costs. This article will discuss recent progress in key areas central
to this reinvention, including miniaturization of cells and optics to produce compact, lightweight
âmicro-CPVâ systems; hybridization of CPV with thermal, illumination and other applications to
make use of unused energy streams such as diffuse light and waste heat; and the integration of
sun-tracking into the CPV module architecture to enable greater light collection and more flexible
deployment, including integration into built structures. Applications showing particular promise
include thermal applications such as water heating, industrial processes and desalination; agricultural
photovoltaics; building-integrated photovoltaics with dynamic daylighting capabilities; and chemical
processes including photocatalysis and hydrogen production. By appropriately tailoring systems
to the available solar resource and local energy demand, we demonstrate how CPV can finally
achieve real-world efficiencies, or solar resource utilization factors, far higher than those of standard
silicon-based PV systems. This makes the argument for sustained development of novel CPV designs
that can be applied to the real-world settings where this efficiency boost will be most beneficial
Efficiency enhancement in two-cell CIGS photovoltaic system with low-cost optical spectral splitter.
Spectrum splitting represents a valid alternative to multi-junction solar cells for broadband light-to-electricity conversion. While this concept has existed for decades, its adoption at the industrial scale is still stifled by high manufacturing costs and inability to scale to large areas. Here we report the experimental validation of a novel design that could allow the widespread adoption of spectrum splitting as a low-cost approach to high efficiency photovoltaic conversion. Our system consists of a prismatic lens that can be manufactured using the same methods employed for conventional CPV optic production, and two inexpensive CuInGaSe(2) (CIGS) solar cells having different composition and, thus, band gaps. We demonstrate a large improvement in cell efficiency under the splitter and show how this can lead to substantial increases in system output at competitive cost using existing technologies
Progress in crystal extraction and collimation
Recent IHEP Protvino experiments show efficiencies of crystal-assisted slow
extraction and collimation of 85.3+-2.8%, at the intensities of the channeled
beam on the order of 10^12 proton per spill of 2 s duration. The obtained
experimental data well follows the theory predictions. We compare the
measurements against theory and outline the theoretical potential for further
improvement in the efficiency of the technique. This success is important for
the efficient use of IHEP accelerator and for implementation of
crystal-assisted collimation at RHIC and slow extraction from AGS onto E952,
now in preparation. Future applications, spanning in the energy from order of 1
GeV (scraping in SNS, slow extraction from COSY and medical accelerators) to
order of 1 TeV and beyond (scraping in Tevatron, LHC, VLHC), can benefit from
these studies.Comment: 7pp. Presented at HEACC 2001 (Tsukuba, March 25-30
Crystal experiments on efficient beam extraction
Silicon crystal was channeling and extracting 70-GeV protons from the U-70
accelerator with efficiency of 85.3+-2.8% as measured for a beam of 10^12
protons directed towards crystals of 2 mm length in spills of 1-2 s duration.
The experimental data follow very well the prediction of Monte Carlo
simulations. This success is important to devise a more efficient use of the
U-70 accelerator in Protvino and provides a crucial support for implementation
of crystal-assisted collimation of gold ion beam in RHIC and slow extraction
from AGS onto E952, now in preparation at Brookhaven Nat'l Lab. Future
applications, spanning in the energy from sub-GeV (medical) to order of 1 GeV
(scraping in the SNS, extraction from COSY) to order of 1 TeV and beyond
(scraping in the Tevatron, LHC, VLHC), can benefit from these studies.Comment: 12pp. Presented at 19-th Intern. Conference on Atomic Collisions in
Solids (ICACS-19: Paris, July 29 - August 3, 2001
Highly efficient crystal deflector for channeling extraction of a proton beam from accelerators
The design and performance of a novel crystal deflector for proton beams are
reported. A silicon crystal was used to channel and extract 70 GeV protons from
the U-70 accelerator in Protvino with an efficiency of 85%, as measured for a
beam of ~1e12 protons directed towards crystals of ~2 mm length in spills of ~2
s duration. Experimental data agree with the theoretically predicted Monte
Carlo results for channeling. The technique allows one to manufacture a very
short deflector along the beam direction (2 mm). Consequently, multiple
encounters of circulating particles with the crystal are possible with little
probability of multiple scattering and nuclear interactions per encounter.
Thus, drastic increase in efficiency for particle extraction out of the
accelerator was attained. We show the characteristics of the crystal- deflector
and the technology behind it. Such an achievement is important in devising a
more efficient use of the U-70 accelerator and provides crucial support for
implementing crystal-assisted slow extraction and collimation in other
machines, such as the Tevatron, RHIC, the AGS, the SNS, COSY, and the LHC.Comment: Presented at PAC 2003 (Portland, May 12-16
Crystal Deflector for Highly-efficient Channelling Extraction of a Proton Beam from Accelerators
The design and manufacturing details of a new crystal deflector for proton beams are reported. The technique allows one to manufacture a very short deflector along the beam direction (2 mm). Thanks to that, multiple encounters of circulating particles with the crystal are possible with a reduced probability of multiple scattering and nuclear interactions per encounter. Thus, drastic increase in efficiency for particle extraction out of the accelerator was attained (85%) on a 70-GeV proton beam. We show the characteristics of the crystal-deflector and the technology behind it
The Investigations Of Beam Extraction And Collimation At U-70 Proton Synchrotron Of IHEP By Using Short Silicon Crystals
The new results of using short (2-4mm) bent crystals for extraction and
collimation of proton beam at IHEP 70 Gev proton synchrotron are reported. A
broad range of energies from 6 to 65 GeV has been studied in the same crystal
collimation set-up. The efficiency of extraction more than 85% and intensity
more than 10E12 were obtained by using crystal with the length 2-mm and the
angle 1 mrad. The new regime of extraction is applied now at the accelerator to
deliver the beam for different experimental setups within the range of
intensity 10E7-10E12ppp.Comment: Presented at EPAC 2002 (Paris, June 3-7), 3p
Crystal deflector for highly efficient channeling extraction of a proton beam from accelerators
The design and manufacturing details of a new crystal deflector for proton beams are reported. The technique allows one to manufacture a very short deflector along the beam direction (2 mm). Thanks to that, multiple encounters of circulating particles with the crystal are possible with a reduced probability of multiple scattering and nuclear interactions per encounter. Thus, drastic increase in efficiency for particle extraction out of the accelerator was attained (85%) on a 70 GeV proton beam. We show the characteristics of the crystal deflector and the technology behind it
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