Showing posts with label alternative power. Show all posts
Showing posts with label alternative power. Show all posts

Friday, July 11, 2008

Better Solar Cells

It is amazing how when one does research into a technology, that technology can get better.

Science 11 July 2008:
Vol. 321. no. 5886, pp. 226 - 228

High-Efficiency Organic Solar Concentrators for Photovoltaics
Michael J. Currie, Jonathan K. Mapel, Timothy D. Heidel, Shalom Goffri, Marc A. Baldo

The cost of photovoltaic power can be reduced with organic solar concentrators. These are planar waveguides with a thin-film organic coating on the face and inorganic solar cells attached to the edges. Light is absorbed by the coating and reemitted into waveguide modes for collection by the solar cells. We report single- and tandem-waveguide organic solar concentrators with quantum efficiencies exceeding 50% and projected power conversion efficiencies as high as 6.8%. The exploitation of near-field energy transfer, solid-state solvation, and phosphorescence enables 10-fold increases in the power obtained from photovoltaic cells, without the need for solar tracking.

Monday, February 25, 2008

Biofuels won't fix it.

Pretty much every issue of Trends in Ecology and Evolution has a paper or two worth the reading. I thought this one was worth drawing your attention to:

Christopher B. Field, J. Elliott Campbell and David B. Lobell. 2008. Biomass energy: the scale of the potential resource. Trends in Ecology & Evolution. Volume 23, Issue 2, Pages 65-72

Abstract:
Increased production of biomass for energy has the potential to offset substantial use of fossil fuels, but it also has the potential to threaten conservation areas, pollute water resources and decrease food security. The net effect of biomass energy agriculture on climate could be either cooling or warming, depending on the crop, the technology for converting biomass into useable energy, and the difference in carbon stocks and reflectance of solar radiation between the biomass crop and the pre-existing vegetation. The area with the greatest potential for yielding biomass energy that reduces net warming and avoids competition with food production is land that was previously used for agriculture or pasture but that has been abandoned and not converted to forest or urban areas. At the global scale, potential above-ground plant growth on these abandoned lands has an energy content representing ~5% of world primary energy consumption in 2006. The global potential for biomass energy production is large in absolute terms, but it is not enough to replace more than a few percent of current fossil fuel usage. Increasing biomass energy production beyond this level would probably reduce food security and exacerbate forcing of climate change.

Sunday, October 14, 2007

Windbelt

This is a really cool invention my friend Brent brought to my attention. It would be incredibly useful in places like PNG where solar doesn't work because it is always raining.