Friday, September 29, 2017
Wednesday, September 27, 2017
Energy can be harvested from evaporation from lakes and rivers and could potentially power much of US ....New Study
Credit: Columbia University
In the first evaluation of evaporation as a renewable energy source, researchers at Columbia University find that U.S. lakes and reservoirs could generate 325 gigawatts of power, nearly 70 percent of what the United States currently produces.
Though still limited to experiments in the lab, evaporation-harvested power could in principle be made on demand, day or night, overcoming the intermittency problems plaguing solar and wind energy. The researchers' calculations are outlined in the Sept. issue of Nature Communications.
"We have the technology to harness energy from wind, water and the sun, but evaporation is just as powerful," says the study's senior author Ozgur Sahin, a biophysicist at Columbia. "We can now put a number on its potential."
Evaporation is nature's way of cycling water between land and air. Sahin has previously shown how this basic process can be exploited to do work. One machine developed in his lab, the so-called Evaporation Engine, controls humidity with a shutter that opens and closes, prompting bacterial spores to expand and contract. The spores' contractions are transferred to a generator that makes electricity. The current study was designed to test how much power this process could theoretically produce.
One benefit of evaporation is that it can be generated only when needed. Solar and wind power, by contrast, require batteries to supply power when the sun isn't shining and wind isn't blowing. Batteries are also expensive and require toxic materials to manufacture.
"Evaporation comes with a natural battery," said study lead author, Ahmet-Hamdi Cavusoglu, a graduate student at Columbia. "You can make it your main source of power and draw on solar and wind when they're available." Evaporation technology can also save water. In the study, researchers estimate that half of the water that evaporates naturally from lakes and reservoirs into the atmosphere could be saved during the energy-harvesting process. In their model, that came to 25 trillion gallons a year, or about a fifth of the water Americans consume.
States with growing populations and sunnier weather can best capitalize on evaporation's capacity to generate power and reduce water waste, in part because evaporation packs more energy in warm and dry conditions, the researchers say. Drought-prone California, Nevada and Arizona could benefit most.
The researchers simplified their model in several ways to test evaporation's potential. They limited their calculations to the United States, where weather station data are readily accessible, and excluded prime locations such as farmland, rivers, the Great Lakes, and coastlines, to limit errors associated with modeling more complex interactions. They also made the assumption that technology to harvest energy from evaporation efficiently is fully developed.
Klaus Lackner, a physicist at Arizona State University who was not involved in the study, expressed support for the team's findings. Lackner is developing artificial trees that draw carbon dioxide from the air, in part, by harnessing the power of evaporation.
"Evaporation has the potential to do a lot of work," he said. "It's nice to see that drying and wetting cycles can also be used to collect mechanical energy."
The researchers are working to improve the energy efficiency of their spore-studded materials and hope to eventually test their concept on a lake, reservoir, or even a greenhouse, where the technology could be used to simultaneously make power and limit water loss.
"We have the technology to harness energy from wind, water and the sun, but evaporation is just as powerful," says the study's senior author Ozgur Sahin, a biophysicist at Columbia. "We can now put a number on its potential."
Evaporation is nature's way of cycling water between land and air. Sahin has previously shown how this basic process can be exploited to do work. One machine developed in his lab, the so-called Evaporation Engine, controls humidity with a shutter that opens and closes, prompting bacterial spores to expand and contract. The spores' contractions are transferred to a generator that makes electricity. The current study was designed to test how much power this process could theoretically produce.
One benefit of evaporation is that it can be generated only when needed. Solar and wind power, by contrast, require batteries to supply power when the sun isn't shining and wind isn't blowing. Batteries are also expensive and require toxic materials to manufacture.
"Evaporation comes with a natural battery," said study lead author, Ahmet-Hamdi Cavusoglu, a graduate student at Columbia. "You can make it your main source of power and draw on solar and wind when they're available." Evaporation technology can also save water. In the study, researchers estimate that half of the water that evaporates naturally from lakes and reservoirs into the atmosphere could be saved during the energy-harvesting process. In their model, that came to 25 trillion gallons a year, or about a fifth of the water Americans consume.
The researchers simplified their model in several ways to test evaporation's potential. They limited their calculations to the United States, where weather station data are readily accessible, and excluded prime locations such as farmland, rivers, the Great Lakes, and coastlines, to limit errors associated with modeling more complex interactions. They also made the assumption that technology to harvest energy from evaporation efficiently is fully developed.
Klaus Lackner, a physicist at Arizona State University who was not involved in the study, expressed support for the team's findings. Lackner is developing artificial trees that draw carbon dioxide from the air, in part, by harnessing the power of evaporation.
"Evaporation has the potential to do a lot of work," he said. "It's nice to see that drying and wetting cycles can also be used to collect mechanical energy."
The researchers are working to improve the energy efficiency of their spore-studded materials and hope to eventually test their concept on a lake, reservoir, or even a greenhouse, where the technology could be used to simultaneously make power and limit water loss.
Sunday, September 17, 2017
The Unicorn of the sea ( Norwhals) Endangered
The narwhal looks like a cross between a whale and a unicorn with its long, spiraled tusk jutting from its head. Males most commonly have tusks, and some may even have two. The tusk, which can grow as long as 10 feet, is actually an enlarged tooth. Ongoing research by WWF collaborators indicates that the tusk has sensory capability, with up to 10 million nerve endings inside. The tusk may also play a role in the ways males exert dominance.
Narwhals spend their lives in the Arctic waters of Canada, Greenland, and Norway. The majority of the world’s narwhals winter for up to five months under the sea ice in the Baffin Bay-Davis Strait area (between Canada and western Greenland). Cracks in the ice allow them to breathe when needed, especially after dives, which can be up to a mile and a half deep. They feed mainly on Greenland halibut, along with other fish, squid and shrimp.
Narwhals have been listed as endangered since 2008. Very few laws have been proposed in attempts to protect this interesting species. In an effort to support conservation, the European Union established an import ban on tusks. Narwhals are becoming extinct for three main reasons. The primary catalyst for the series of events that have led to decrease narwhal populations is unprecedentedly rapid climate change.
Thousands of years of evolution have prepared an Arctic species like the narwhal for life on and around the sea ice. Because of climate change, this ice cover has dramatically decreased in both extent and thickness, at a rate far too quick for a species to adapt. A narwhal relies on sea ice for a place to feed and a place to take refuge—occasionally even a place to hide from predators. An additional result of climate change is the reduction in the population of the narwhal’s primary prey, the Greenland halibut.
Melting Arctic ice
Also encumbering rehabilitation efforts for the narwhal species is the increase in oil and gas development. The increased shipping of oil and gas has lead to increased shipping movement in sensitive areas. In addition to the possibility of fatal oil spills, collisions between boats and many species of marine life are certain to occur. Also, shipping, marine construction and military activities cause an increase in noise pollution. Whales, as well as many other marine species, rely heavily on sound for communication. This new interference by noise pollution can negatively affect a narwhal’s ability to find food and mates, navigate, avoid predators and take care of their young. “Man-made noise affects sea creatures like putting a bucket on your head. It cuts off the senses they need to survive. When they can’t hear, they can’t live”
Finally, hunting with modern equipment represents the most long-standing and consistent threat to narwhals throughout their habitat-range. Are Norwhals important??? Every link in the food chain is absolutely essential to the link that came before and the link that comes after it and the link after that. That food chain eventually makes it's way to humans, who consider themselves at the top of the chain. When those links start disappearing one by one so does our food.
It's like this...a little fish, while eating a shrimp, gets eaten by a bigger fish, which gets eaten by a bigger fish and so on until the last fish in the line is a huge marlin which is then caught by a man and eaten. That is how the food chain works. So even the species that aren't too pretty, like the narwhals hold an important place in the survival of the life on our planet.
Thursday, September 14, 2017
Monster from the Deep
When Preeti Desai was trying to assess the damage caused by Hurricane Harvey, she accidentally stumbled upon the depths of hell.
"What the heck is this indeed", Ms Desai.
The spine-chilling monster with its thick, serpent-like body, daggered teeth and NO EYES had social media stumped - the only thing they knew was that they were never going to swim again.
Some commenters threw out the suggestion of eel and a biologist agreed, telling the BBC it was a fangtooth snake-eel.
Fangtooth snake-eel. Oh okay then, so just a mixture of all of the worst things in the world – cool.
Dr Kenneth Tighe, a biologist and eel specialist, said it could be a conger or garden eel as "all three of these species occur off Texas and have large fang-like teeth".
Ms Desai, who is a part of the Audubon Society – a non-profit group dedicated to conservation, said she was seeing how extensively Hurricane Harvey had damaged the environment when she stumbled upon the creature.
"It was completely unexpected, it's not something that you'd typically see on a beach. I thought it could be something from the deep sea that might have washed on to shore," she reported.
"My main reaction was curiosity, to figure out what the heck it was."
She also said she left the horrifying monster eel on the beach "to let nature take its course".
But, monster or not, it is a citizen of earth, obviously a predator. I have seen conger eels but never one this huge. There are hundreds of thousands of aquatic species. Any average person has only ever seen a couple of hundred. With the oceans getting more acidic and warmer, thousands of these species hover on the brink of extinction.
The rapid loss of species we are seeing today is estimated by experts to be between 1,000 and 10,000 times higher than the natural extinction rate.
These experts calculate that between 0.01 and 0.1% of all species are becoming extinct each year.
Tuesday, September 5, 2017
Weep for What We Have Done
Death from exhaustion.
The Arctic Ocean is now the garbage dump at the top of the world. The ocean currents bring trash from all over the world.
It is almost too much to bear. Where do we begin??
How do we change people's thinking??
We must never give up trying.
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