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  speculative: claimed new fuel-cell battery combination - which i don’t fully get!
[Original article in the Royal Society of Chemistry Journal.]

Claims to be taken with caution.

This item is being reported in various places with a degree of confusion. The technology is alleged to produce a useful energy at a density higher than petrol (gas) or diesel, and at an order of magnitude (ten times) higher than lithium battery technology.

The claim seems to be that this fuel-cell battery combination can be charged like an ‘ordinary’ battery and, when the charge is run down, the combination becomes a fuel cell. The fuel cell/battery cannibalises energy in some manner from its vanadium-boride anode, as it then acts as a fuel-cell. The anode can then be replaced., for instance at a garage in the manner of a petrol fill-up, and the anode can then be returned to functionality.

There are also suggestions that other combinations, including lithium and aluminium-[aluminum]-based systems, can be developed in this direction.

I get the impression that the reports I have seen so far are written by authors who do not fully understand the claims, and I certainly do not have a good outline grasp of the system!

So, I am linking this report for others to look at, without much confidence that I understand it!

“Energy capacity comparison of gasoline (petrol), hydrogen and electrochemical energy sources. The intrinsic energy of gasoline yields a maximum practical efficiency of 30% due to Carnot and friction losses. Air fuel cells do not have this Carnot inefficiency, and have practical capacities instead constrained by overpotential losses, and the requisite volume of the air anode and all other cell components. Volumetric capacity of liquid H2 is constrained by its density of 0.0708 kg L-1. Shaded superimposed on solid, colors, compare intrinsic and practical capacities.”

related material
Fuel cells and battery-powered vehicles
claim of producing hydrogen locally at normal temperatures - also, algae to petrol/gasoline

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alleged solar thermal concentrator

Another attempt/claim at solar thermal concentration..

“In their prototype, they concentrated sunlight up to 5,000 times the intensity that normally would fall on a surface on earth. This immense solar concentration can create heat at the focal point that approach the surface temperature of the sun at 6,000 °C (11,000 °F). Metal placed at the focus is instantly melted. In commercial scale systems, SHEC expects that the concentrations could be as high as 11,000 to 16,000 times the intensity of the sun.

“In practice, the objective is to not let the receiver get that hot. This is accomplished by continuously pulling off the heat into whatever the system is designed to do.”
—
“This array will result in a 11,000-fold concentration of the sun's energy.”
—
“While the capitalization costs of a SHEC array will be greater than for a fossil-fuel-based plant of comparable output, the operational costs are much lower, not requiring fuel, for example. So the payback time is in the region of five to fifteen years. Compare that to the 50 year amortization schedule common for a hydroelectric plant, for example.”

related material
concentrators

attempt at another form of concentrator for pv cells

MIT press release:

“As a result, rather than covering a roof with expensive solar cells (the semiconductor devices that transform sunlight into electricity), the cells only need to be around the edges of a flat glass panel. In addition, the focused light increases the electrical power obtained from each solar cell "by a factor of over 40," Baldo says."
—
“ The MIT solar concentrator involves a mixture of two or more dyes that is essentially painted onto a pane of glass or plastic. The dyes work together to absorb light across a range of wavelengths, which is then re-emitted at a different wavelength and transported across the pane to waiting solar cells at the edges.

“In the 1970s, similar solar concentrators were developed by impregnating dyes in plastic. But the idea was abandoned because, among other things, not enough of the collected light could reach the edges of the concentrator. Much of it was lost en route.

“The MIT engineers, experts in optical techniques developed for lasers and organic light-emitting diodes, realized that perhaps those same advances could be applied to solar concentrators. The result? A mixture of dyes in specific ratios, applied only to the surface of the glass, that allows some level of control over light absorption and emission. "We made it so the light can travel a much longer distance," Mapel says. "We were able to substantially reduce light transport losses, resulting in a tenfold increase in the amount of power converted by the solar cells." ”

Image: NSF

“An artist's representation shows how a cost effective solar concentrator could help make existing solar panels more efficient. The dye-based organic solar concentrator functions without the use of tracking or cooling systems, greatly reducing the overall cost compared to other concentrator technologies. Dye molecules coated on glass absorb sunlight, and re-emit it at a different wavelengths. The light is trapped and transported within the glass until it is captured by solar cells at the edge. Some light passes through the concentrator and can be absorbed by lower voltage solar cells underneath. Alternatively, the partially transmissive concentrator can function as a window.”

on bird relationships

“A new study – the largest analysis of birds to date using modern genetic methods – has turned up numerous surprising relationships that will force biologists to reevaluate much of what they thought they knew about avian evolution.”
—
“To resolve this problem, Reddy and her colleagues sequenced 19 regions of the genome of 169 species of birds – a total of 32,000 DNA "letters" per species – then used the sequences to construct the most robust avian evolutionary tree ever made.

“This new tree contains several notable surprises. For example, falcons are more closely related to songbirds than to other hawks and eagles. The closest kin of the diving birds called grebes turn out to be flamingos. [...]”

related material
human classification systems, using the example of classification of ‘living organisms’ (taxonomy)

global warming > less ice > less krill > less whales

WWF predictions based on an assumption that average temperatures will rise by 2.0 degrees Celsius by 2042.

“As well as retreating, the vital front between cold sea ice and warmer sea water which causes an upwelling of nutrients supporting the krill on which the whales feed will also contract, reducing the amount of food available.

“ "Essentially, what we are seeing is that ice-associated whales such as the Antarctic minke whale will face dramatic changes to their habitat over little more than the lifespan of an individual whale," [...]”
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“Especially at risk from the retreating Antarctic sea ice are the Blue Whale, the world's largest living creature, and the Humpback Whale.”

related material
antarctica melting ice, sea levels, water and weather implications
arctic melting ice, sea levels
global warming

  globally, is there is enough land?

Useful scan.

“Strictly speaking, there is no global shortage of land. Cereal production peaked at around 740m hectares in 1981 and slid steadily for over two decades before recovering a little in the latest revival to 680m, according to the FAO.”

Link from Mel Rowing.

high claims for innovative automotive transmission system

“In confirmed third-party tests, the U.K. Energy Saving Trust, a grant supplier for the project, says Artemis’ prototype BMW 530i hydraulic series hybrid, outfitted with HEDDAT (High Efficiency Digital Displacement Automotive Transmission) technology performed with double the MPG in city tests (a start and stop environment) of the same car with a manual transmission.

“Additionally, Artemis and the Energy Saving Trust say the performance of the BMW prototype, including highway driving, revealed 30 per cent lower CO2 emissions before the company fitted the hydraulic transmission.”
—
“Whenever there’s a lot of starting and stopping, that’s where we’ll beat electric hybrids," said Caldwell. "We can store energy at a faster rate.”

Artimis page on the Digital Displacement technology.

Artimis page on Digital Displacement Hybrid Transmissions.

emissions reduction test results
driving conditions	six speed manual	Artimis digital displacement hybrid	percentage by which less CO2 produced
European urban	20.4 mpg	41.1 mpg	50%
European combined (urban+motorway)	29.7 mpg	39.6 mpg	30%
US combined (urban+motorway)	27.9 mpg	42.1 mpg	34%

solar cell avalanche effect could improve output - from xavier

Visualisation of avalanche effect. Credit: TU Delft
Rough text translations:
foto-excitatie - incoming photons
thermische relaxatie - conventional solar cell
ladingsvermenigvuldiging -semiconducting nanocrystal

“[...] there are currently significant limitations, such as the relatively low output of most solar cells (typically fifteen percent) and high manufacturing costs.”
—
“In conventional solar cells, one photon (light particle) can release precisely one electron.”
—
“In some semiconducting nanocrystals, however, one photon can release two or three electrons, hence the term avalanche effect.”
—
“Within the Joint Solar Programme TU Delft’s Prof. Laurens Siebbeles has now demonstrated that the avalanche effect does indeed occur in lead selenide (PbSe) nanocrystals.”

Abstract of original paper (paid subscription necessary to see full document).

related material
photovoltaics (solar cells)

on the genetics of the platypus

Image: epa.qld.gov.au

“Is the platypus part bird, part reptile part mammal, an amalgam of very different groups of animals? Is it a primitive mammal that resembles the early ancestors of all mammals? Can we figure out just what this creature is by gazing at its genome?”
—
“The platypus is not part anything: it's 100% mammal, with some primitive traits of ancient mammals, like egg laying, and a few newly invented traits like the bill, the webbed feet, and the venomous spines.

“The big story hidden in the platypus genome is that evolutionary biologists were right about what the platypus is: by looking at its genome, we can see which platypus traits are ancestral, and which are new inventions (derived is the proper term), only now in much more detail because we can see how the genes involved changed.”

ddt killing penguins - but why? ddt is now mostly banned

“The use of DDT peaked several decades ago at more than 36,000 metric tons per year (t/yr). Today, less than 1000 t of the organochlorine pesticide—banned in most countries since the 1980s—is applied annually for mosquito control and farming, mainly in the Southern Hemisphere. Despite this drop, Adélie penguins in the Antarctic continue to have the same levels of total DDT in their bodies as they did 30 years ago. New research [...] identifies Antarctic meltwater as the continued source of total DDT, and possibly other pollutants, in the southern continent's ecosystems.”

“In 1958, Olga Owens Hucking, the owner of a private bird sanctuary in Duxbury, Massachusetts sent a letter to Carson. Ms. Hucking was alarmed at the dead and dying birds at her sanctuary. That letter may have been the deciding factor prompting Carson's next book. It was clear to Carson that the issue of pesticides had to be addressed in a book with a tone different than her earlier writings. Her book, Silent Spring, was published in 1962. In it, Carson addressed the dangers posed by DDT and the dangers of a society blinded by technological progress.

“The evidence was undisputedly conclusive that DDT interfered with calcium metabolism in birds at the top of the food chain. With no mechanism to excrete or breakdown DDT, birds at the top of the food chain accumulated DDT as they ate smaller birds, which, in turn, ate insects exposed to DDT. The interference with calcium metabolism caused thinning eggshells that broke easily.” [Quoted from dep.state.pa.us]

The negative response to using DDT, and its widespread ban, led to the re-emergence of malaria. DDT had kept malaria mosquito populations under control. It is now understood that selective spraying of houses with DDT can control mosquito infestation without damaging bird and plantlife.

related material
malaria

Silent Spring by Rachel Carson first published in 1962 Penguin Classics, 2000 ISBN-10: 0141184949 ISBN-13: 978-0141184944 £6.99 [amazon.co.uk] {advert} Mariner Books, 2002 ISBN-10: 0618249060 ISBN-13: 978-0618249060 $10.17 [amazon.com] {advert}

the potential of tethered windmills

The Magenn company have got the tethered rotor windmill to work in a hanger.

A list of claims

• Magenn Air Rotor System is less expensive per unit of actual electrical energy output than competing wind power systems.
• Magenn Power Air Rotor System will deliver time-averaged output much closer to its rated capacity than the capacity factor typical with conventional designs. Magenn efficiency will be 40 to 50 percent. This is hugely important, since doubling capacity factor cuts the cost of each delivered watt by half.
• Wind farms can be placed closer to demand centers, reducing transmission line costs and transmission line loses.
• Conventional wind generators are only operable in wind speeds between 3 meters/sec and 28 meters/sec. Magenn Air Rotors are operable between 1 meter/sec and in excess of 28 meters/sec.
• Magenn Air Rotors can be raised to higher altitudes, thus capitalizing on higher winds aloft. Altitudes from 400-ft to 1,000-ft above ground level are possible, without having to build an expensive tower, or use a crane to perform maintenance.
• Magenn Air Rotors are mobile and can be easily moved to different locations to correspond to changing wind patterns. Mobility is also useful in emergency deployment and disaster relief situations.

related material
Wind power

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