[amor de cosmos]

Solar Power's Future Brawl
Simulations Help North and South Dakota Researchers Decide Which Technology Would Make a Better Solar Collector, Quantum Dot or Nanowire
Released: 10/1/2013 1:45 PM EDT
Source Newsroom: American Institute of Physics (AIP)

Newswise — WASHINGTON, D.C. Oct. 1, 2013 -- A trio of researchers at North Dakota State University, Fargo and the University of South Dakota have turned to computer modeling to help decide which of two competing materials should get its day in the sun as the nanoscale energy-harvesting technology of future solar panels -- quantum dots or nanowires.

Andrei Kryjevski and his colleagues, Dimitri Kilin and Svetlana Kilina, report in AIP Publishing's Journal of Renewable and Sustainable Energy that they used computational chemistry models to predict the electronic and optical properties of three types of nanoscale (billionth of a meter) silicon structures with a potential application for solar energy collection: a quantum dot, one-dimensional chains of quantum dots and a nanowire. The ability to absorb light is substantially enhanced in nanomaterials compared to those used in conventional semiconductors. Determining which form -- quantum dots or nanowire -- maximizes this advantage was the goal of the numerical experiment conducted by the three researchers.

"We used Density Functional Theory, a computational approach that allows us to predict electronic and optical properties that reflect how well the nanoparticles can absorb light, and how that effectiveness is affected by the interaction between quantum dots and the disorder in their structures," Kryjevski said. "This way, we can predict how quantum dots, quantum dot chains and nanowires will behave in real life even before they are synthesized and their working properties experimentally checked."

http://www.newswise.com/articles/sol...s-future-brawl

News Release NR-5113
NREL Releases New Roadmap to Reducing Solar PV “Soft Costs” by 2020
September 25, 2013

The Energy Department’s (DOE) National Renewable Energy Laboratory (NREL) recently issued a new report, “Non-Hardware (‘Soft’) Cost-Reduction Roadmap for Residential and Small Commercial Solar Photovoltaics, 2013–2020,”PDF funded by DOE’s SunShot Initiative and written by NREL and Rocky Mountain Institute (RMI). The report builds off NREL’s ongoing soft-cost benchmarking analysis and charts a path to achieve SunShot soft-cost targets of $0.65/W for residential systems and $0.44/W for commercial systems by 2020.

Non-hardware costs — also referred to as soft, balance of system, or business process costs — include permitting, inspection, interconnection, overhead, installation labor, customer acquisition, and financing. The report also highlights that certain processes often categorized as soft costs, such as permitting and interconnection, may not appear significant when measured in terms of dollars-per-watt, but are costly in that they pose significant market barriers which slow PV deployment.

“Regardless of the specific path taken to achieve the SunShot targets, the concerted efforts of numerous photovoltaic (PV) market stakeholders will be required,” NREL Solar Technology Markets and Policy Analyst Kristen Ardani said. “This report illustrates how the required participation of each type varies substantially by soft-cost-reduction category while noting that roles and responsibilities will be complementary and evolve over time.”

“Soft costs are the majority of costs for residential solar and a large minority for commercial PV projects. They have remained stubbornly high in recent years despite impressive hardware-costs reductions,” said Jon Creyts, program director at Rocky Mountain Institute. “Aggressive soft-cost-reduction pathways must be developed to achieve the SunShot Initiative’s PV price targets.”

Soft costs account for more than 50 percent of total installed residential solar costs and more than 40 percent of commercial solar costs. The report covers strategies to overcoming market barriers and decreasing costs across four key areas: customer acquisition; permitting, inspection, and interconnection; installation labor; and financing. The report identifies residential installation labor, and permitting, inspection, and interconnection as facing the most uncertain near-term paths toward roadmap targets.

http://www.nrel.gov/news/press/2013/3301.html