Friday, March 30, 2007
The solar panels, which are raised around 2 meters off the ground, cover an area of 60 hectares (150 acres) and produce 11 megawatts of electricity in one of Europe's sunniest spots -- Portugal's poor agricultural Alentejo region.
The plant, which has 52,000 photovoltaic modules, is near the town of Serpa, 125 miles southeast of Lisbon.
The scheme fits into Portugal's plans of reducing its reliance on imported energy and cutting output of greenhouse gasses that feed global warming.
Portugal's emissions have surged about 37 percent since 1990, one of the highest increases in the world.
By bringing modern technology to one of western Europe's poorest regions, the $75-million plant is expected to bring alternative development to the Alentejo.
Output of U.S. ethanol, which is mostly made from corn, is expected to jump in 2007 from 5.6 billion gallons per year to 8 billion gpy, as nearly 80 bio-refineries sprout up.
Corn prices have doubled over the last year as the Bush administration, seeking to reduce oil imports while boosting output of fuels believed to cut greenhouse gas emissions, offers millions of dollars in incentives to boost ethanol production.
The corn prices, the highest in a decade, have spurred thousands of people in Mexico to protest over the price of tortillas, a national staple made from corn. The spike has also lead to worries that meat and dairy prices could eventually rise.
Sell said the future of biofuels is cellulosic ethanol, made from microbes that break down woody bits of non-food crops into sugars that can be fermented into fuel.
Cellulosic, and other new biofuels such as biobutanol, which can be made from petroleum as well as biomass, could begin to feed the commercial fuel market within six to 10 years, he said. They could also be part of a larger program to cut greenhouse gases, he added.
In a related incident El Commandate has condemed the use of food to produce automotive fuel. An excerpt from a conversation beween Chavez and Castro published by the BBC is below.
BBC: The following is the transcript of the conversation between Venezuela's President Hugo Chavez and Cuban leader Fidel Castro. It has been edited for brevity.
...Chavez: Do you know how many hectares of corn are needed to produce one million barrels of ethanol?
Castro: To do what?
Chavez: To produce one million barrels of ethanol?
Castro: Ethanol. I believe you told me about that the other day. Somewhere around 20 million hectares.
Chavez:[Laughing] Just like that.
Castro: Go ahead, remind me.
Chavez: Indeed, 20 million. You are the one with an exceptional mind, not me.
Castro: Twenty million. Well, of course. The idea of using food to produce fuel is tragic, is dramatic. No one is sure how high the price of food will rise when soy is being used for fuel, with the need there is in the world to produce eggs, milk, to produce meat. It is a tragedy. One of many today.
Thursday, March 29, 2007
Humans are getting better at smaller things. This nano guitar modeled after a stratocaster is a about 10 microns long and is actually playable. The pick you will have to use is an atomic force microscope ! Made my the mavens at Cornel.
Wednesday, March 28, 2007
Lumileds (Philips now) has finally released the latest and greatest in low form factor power led's. The high efficacy (upt 72 lm/W) LED boasts a high Tj of 150 deg C. This is quite an innovation and can provide a much needed shot in the arm for LED general illumination space. Alternate Lighting (where i work) has already created some reference designs that will use this semiconductor. Currently this led is seen to have a large potential in the solar lighting and AC dowlighting (MR16, 11 etc) markets.
From the article in LED mag
The Rebel contains a 1x1 mm2 chip and has a footprint of just 3mm x 4.5mm, considerably smaller than rival power LEDs. The chip is mounted on a ceramic substrate and has a hemispherical silicone lens. The Rebel is engineered for operation between 350 mA and 1000 mA, and is the first power LED to offer guaranteed minimum performance (many datasheets for other LEDs specify typical performance values). Lumileds says that its minimum performance specifications enable greater design and manufacturing consistency, and allow customers to purchase the light output performance appropriate for each application.
The Rebel white binning structure includes a CCT range from 2670K to 3500K for warm-white, 3500K to 4500K for neutral-white, and 4500K to 10000K for cool-white. Sampling of the warm-white and neutral-white products begins immediately with volume production later this year.
For each CCT range, there are several bins with different minimum performance; 40, 50, 70 and 80 lm at 350 mA for cool- and neutral-white. With a forward voltage of 3.15 V, the highest bin has an efficacy of around 72 lm/W.
At higher drive currents, the datasheet shows that the top bins deliver 145 lm at 700 mA in cool- and neutral-white (57 lm/W), and 110 lm for warm-white (43 lm/W).
Typical color-rendering index (CRI) is 80 for warm-white, 75 for neutral-white, and 70 for cool-white.
The package's small footprint and low profile of just 2.1mm should enable significantly reduced color mixing and diffusion depths. This will allow luminaire designs that are significantly thinner than those using alternative power LED packages.
Saturday, March 24, 2007
While the green lobby tells us to fiddle with our standby buttons and low-energy light bulbs, no one is willing to address the accelerating growth in the world's population.
IN THE time it takes you to get to the end of this sentence, seven people have been added to the population of the world. At this rate, the United Nations estimates the number of people on the planet will nearly double by the middle of this century. Even with significant reductions in birth rates, the population is expected to increase from 6.7 billion now to 9.2 billion by 2050.
These figures are staggering. Yet there is hardly a mention of them in discussion of global warming and ensuing climate change.
The U.K., for example, last week unveiled its Climate Change Bill promising to cut emissions of carbon dioxide and other greenhouse gases blamed for global warming by 60 per cent from 1990 levels by 2050. Suggested policies to achieve this ranged from banning standby buttons on electrical equipment and old-fashioned, inefficient light bulbs to "capture and storage" of pollution from coal-fired power stations. Others want to limit air travel — a small but fast-growing source of greenhouse gases.
These have been well-intentioned, if not always convincing, ideas. At an Oxford, England, conference, scientists argued against the "Hollywoodisation" of the problem, that it is being promoted beyond the science. And still, everybody is talking only about one half of the equation: the emissions we generate, not how we generate them. All the standby buttons and low-energy light bulbs are dwarfed by the pressure of a global population rising by the equivalent of Britain every year.
Thursday, March 22, 2007
Cree has announced that it is shipping warm white XLamp LEDs that produce up to 124 lumens at a correlated color temperature (CCT) of 3,000 K when driven at 700 mA.
The company claims that this represents the industry's first demonstration of "lighting class" warm-white LEDs.
Times online reports on a creature that has turned the current orthodoxy in evolutionary biology around. Apparently this small rotifer family is all female. Shot in the arm for Lesbian groups :) From the article A tiny creature that has not had sex for 100 million years has overturned the theory that animals need to mate to create variety.
Analysis of the jaw shapes of bdelloid rotifers, combined with genetic data, revealed that the animals have diversified under pressure of natural selection.
Researchers say that their study “refutes the idea that sex is necessary for diversification into evolutionary species”.
The microscopic animals, less than four times the length of a human sperm, are all female, yet have evolved into different species that fill different ecological niches. Two sister species were found to be living together on the body of a water louse. One of them specialised in living around the louse’s legs and the other stayed close to the chest.
Genetic analysis showed that the two creatures were distinct, a fact backed up by observations that each type had differently shaped jaws.
Asexual animals and plants usually die out quickly in evolutionary terms but the ability of bdelloid rotifers to diversify may explain why they have survived so long.
A specimen trapped in amber has shown that the animals were living at least 40 million years ago and DNA studies have suggested they have been around for 100 million years. Modern Man has notched up about 160,000 years.
It had previously been recognised that asexual animals and plants can evolve through mutations into another species, but only into one species and at the cost of its original form. Bdelloid rotifers have displayed the ability to evolve into many different forms.
The study of several bdelloid rotifers, published in the journal PLoS Biology, was carried out by an international team including researchers from Imperial College London, the University of Cambridge and the Royal Botanic Gardens, Kew. “These really are amazing creatures, whose very existence calls into question scientific understanding,” said Tim Barraclough, of Imperial College.
He added that the two species of bdelloid rotifer almost certainly arrived on the louse as one species and later evolved to take better advantage of the environment.
There are many examples of asexual species of animals and plants, including some dande- lions. Asexuality is most common in invertebrates, such as aphids, but it is also found in a number of fish and frogs.
Monday, March 19, 2007
exhibit of "how life used to be." Energy specialists, environmental
activists and Philips Lighting North America recently announced that
they are working together to eliminate the incandescent light bulb in
This is a interesting case of a company trying to kill its own product. Read more here.