http://www.cnn.com/2011/TECH/innovation/06/27/fusion/index.html?hpt=hp_c2
Thursday, June 30, 2011
Wednesday, June 29, 2011
Tuesday, June 28, 2011
GE Funds 10 Energy Startups
www.technologyreview.com
$68 million goes to wireless charging, smart buildings, cooler LEDs and other tech.
Obama has called for all cars to get at least 56.2 MPG by 2025!
Obama Calls for 56.2 MPG Fuel Efficiency Mandate by 2025
inhabitat.com
The Obama administration is bumping up it's aims for fuel efficiency mandates to 56.2 mpg by 2025.
inhabitat.com
The Obama administration is bumping up it's aims for fuel efficiency mandates to 56.2 mpg by 2025.
Are biofuels the future of flight?
www.cnn.com
Some commercial passenger jets will begin flying on biofuels within months, as the airline industry attempts to shed its image as a major source of global pollution.
New solar cell: Engineers crack full-spectrum solar challenge
www.sciencedaily.com
Engineering researchers report a new solar cell that may pave the way to inexpensive coatings that efficiently convert the sun's rays to electricity.
Fwd: Last call for speakers - Opportunity Green 2011
---------- Forwarded message ----------
From: "Karen Solomon" <karen@opportunitygreen2011.com>
Date: Jun 28, 2011 11:01 AM
Subject: Last call for speakers - Opportunity Green 2011
To: John Sokol
From: "Karen Solomon" <karen@opportunitygreen2011.com>
Date: Jun 28, 2011 11:01 AM
Subject: Last call for speakers - Opportunity Green 2011
To: John Sokol
If you're having trouble viewing this email, you may see it online .
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Last chance reminder: the speaker application deadline for Opportunity Green is June 30th! To submit a speaker recommendation, please visit our speaker application page. Stay tuned - registration for the conference begins in July. Karen Solomon Co-Founder and CEO
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Monday, June 27, 2011
Saturday, June 25, 2011
Tuesday, June 14, 2011
Wake galloping wind power , as in Galloping Gertie
From New Scientist: Wind power harnesses the energy of galloping
Now Hyung-Jo Jung and Seung-Woo Lee at the Korea Advanced Institute of Science and Technology in Daejeon, South Korea, plan to harness these destructive forces to generate energy. They have built a prototype that produces energy using a specific type of unstable airflow called wake galloping.
Wake galloping is a form of vigorous vibration that affects cylindrical parts of structures, such as the cables on suspension bridges, exposed to seemingly harmless airflow. When the wind passes a horizontal cylinder, eddy currents called wake vortices are created on the lee side. These induce a lifting force on a cylinder in the path of these eddies - but only if the two have the same diameter and the second cylinder is three to six diameters away from the first.
The leeward cylinder's weight counteracts the lift by pulling it back down again, resulting in the cylinder repeatedly moving up and down as the wind continues to blow. It is this movement that Jung and Lee hope to harness as energy.
To do this, they built a device containing two 85-centimetre long, 5-cm-diameter perspex rods spaced appropriately from each other. The rod on the leeward side was attached to a magnet, which was free to move within a copper coil (see diagram). As the cylinder moved, so did the magnet, generating a current in the coil.
The team found that even at wind speeds between 2.5 to 4.5 metres per second, when traditional wind turbines are inefficient, the system generated nearly half a watt of electrical power. They think this could be improved if the magnets and coils were optimised. The team report their findings in Smart Materials and Structures (DOI: 10.1088/0964-1726/20/5/055022).
"One of the most promising applications for this is monitoring a structure's health using wireless sensors," Jung says. "The device could supply the monitors with power in a bridge or a high-rise building." And if enough of the generators were grouped together, he adds, they could power a bridge's street lighting.
The pair are now attempting to find what Jung calls the "most efficient size of the device" before they attempt to commercialise it.
Jung and Lee are not alone in harnessing unusual aspects of the wind. Humdinger Wind Energy of Honolulu, Hawaii, led by founder Shawn Frayne, is interested in a similar phenomenon called aeroelastic flutter, in which aerodynamic forces reinforce a structure's natural resonance, causing it to vibrate. The most famous example of this occurred in 1940, when the newly opened Tacoma Narrows bridge in Washington state began undulating in a light breeze, earning it the nickname Galloping Gertie. Within four months of completion, the bridge had shaken itself to shreds in a storm.
Frayne has created the Windbelt, which uses aeroelastic flutter to vibrate a plastic ribbon in light to moderate breezes. The vibration moves a magnet through a coil, which generates current in a similar fashion to Jung and Lee's device.
Both will likely find a market, says Matthew Wright of the Institute of Sound and Vibration Research at the University of Southampton in the UK. "There are situations where you need a small amount of power, but in a location that's too remote to connect to the grid, or to deliver fuel or batteries to. One of these devices might well find a niche there."
Sunday, June 5, 2011
Graphene-based supercapacitor hits new energy storage high
From Gizmag: Graphene-based supercapacitor hits new energy storage high
A breakthrough in supercapacitor performance has been achieved with the development of a device that can store as much energy as a battery while recharging in seconds. The graphene-based supercapacitor being developed in the U.S. by researchers at Nanotek Instruments can store as much energy per unit mass as nickel metal hydride batteries and could one day be used to help deliver almost instant charging to recharge mobile phones, digital cameras or micro electric vehicles.
With the high surface area of their electrodes and an extremely narrow gap between the electrodes, supercapacitors, also known as electric double-layer capacitors or electrochemical capacitors, can store a large amount of electrical charge in a tiny volume. The newly developed device has electrodes made graphene mixed with an acetylene black called Super P that acts as a conductive additive and a binder that holds it all together. The resulting slurry is coated onto the surface of a current collector and assembled in coin-sized capacitors. The electrolyte-electrode interface is made of "Celguard-3501" and the electrolyte is a chemical called EMIMBF4.
Specific energy density of the new capacitor (a measure of how much electricity can be stored per weight) has been measured at 85.6 Wh/kg at room temperature and 136 Wh/kg at 80 degrees Celsius (176 F), which is comparable to Ni-mh batteries. These are the best values for electric double layer supercapacitors based on carbon nanomaterials recorded to date.
"This new technology makes for an energy storage device that stores nearly as much energy as in a battery but which can be recharged in seconds or minutes," Jang said. "We believe that this is truly a breakthrough in energy technology."
The team, which includes scientists from Angstron Materials in the U.S. and Dalian University of Technology in China, is now trying to further improve the energy density of the device.
"Our goal is to make a supercapacitor that stores as much energy as the best lithium-ion batteries (for the same weight) but which can still be recharged in less than two minutes," Jang said. "Despite the theoretically high specific surface area of single-layer graphene (which can reach up to 2.675 m2/g), a supercapacitance of 550 F/g has not been reached in a real device because the graphene sheets tend to re-stack together. We are trying to overcome this problem by developing a strategy that prevents the graphene sheets from sticking to each other face-to-face. This can be achieved if curved graphene sheets are used instead of flat ones."
 |
| High surface area of graphene make supercapcitors possible |
With the high surface area of their electrodes and an extremely narrow gap between the electrodes, supercapacitors, also known as electric double-layer capacitors or electrochemical capacitors, can store a large amount of electrical charge in a tiny volume. The newly developed device has electrodes made graphene mixed with an acetylene black called Super P that acts as a conductive additive and a binder that holds it all together. The resulting slurry is coated onto the surface of a current collector and assembled in coin-sized capacitors. The electrolyte-electrode interface is made of "Celguard-3501" and the electrolyte is a chemical called EMIMBF4.
Specific energy density of the new capacitor (a measure of how much electricity can be stored per weight) has been measured at 85.6 Wh/kg at room temperature and 136 Wh/kg at 80 degrees Celsius (176 F), which is comparable to Ni-mh batteries. These are the best values for electric double layer supercapacitors based on carbon nanomaterials recorded to date.
"This new technology makes for an energy storage device that stores nearly as much energy as in a battery but which can be recharged in seconds or minutes," Jang said. "We believe that this is truly a breakthrough in energy technology."
The team, which includes scientists from Angstron Materials in the U.S. and Dalian University of Technology in China, is now trying to further improve the energy density of the device.
"Our goal is to make a supercapacitor that stores as much energy as the best lithium-ion batteries (for the same weight) but which can still be recharged in less than two minutes," Jang said. "Despite the theoretically high specific surface area of single-layer graphene (which can reach up to 2.675 m2/g), a supercapacitance of 550 F/g has not been reached in a real device because the graphene sheets tend to re-stack together. We are trying to overcome this problem by developing a strategy that prevents the graphene sheets from sticking to each other face-to-face. This can be achieved if curved graphene sheets are used instead of flat ones."
Integrating Capacitors Into Car Frames
From Slashdot: Integrating Capacitors Into Car Frames
"It has long been recognized that adding capacitors in parallel with batteries can improve the performance of hybrid and electric vehicles by accepting and supplying spikes of power, which reduces stress on the battery pack, extending range and improving cycle life. The challenge has been figuring out where to put them, when batteries already compete for space. A new research prototype from Imperial College London has integrated them into the body panels and structural frame of the vehicle itself. In their prototype, carbon fiber serves as both the structure for the vehicle and electrode for the energy storage sandwiched within."
"It has long been recognized that adding capacitors in parallel with batteries can improve the performance of hybrid and electric vehicles by accepting and supplying spikes of power, which reduces stress on the battery pack, extending range and improving cycle life. The challenge has been figuring out where to put them, when batteries already compete for space. A new research prototype from Imperial College London has integrated them into the body panels and structural frame of the vehicle itself. In their prototype, carbon fiber serves as both the structure for the vehicle and electrode for the energy storage sandwiched within."
Friday, June 3, 2011
An alternative to Windmills
On NewScientist: Wind power harnesses the energy of galloping
On Slashdot: Harnessing the Energy of Galloping Gertie"You've all seen the footage of Galloping Gertie, the infamous Tacoma Narrows bridge. This is due to a type of turbulence called Wake Galloping, caused by airflow creating lift on the lee-side of cylinders (or cables on suspension bridges.) Now researchers in South Korea have developed a way of harnessing the turbulence to generate electricity. Their device works most efficiently at wind speeds too low for conventional wind turbines."
THE thought of wind power brings visions of giant turbines, high-altitude kites and graceful sailboats to mind. But the breeze has a more sinister side, full of turbulence that can wreak havoc with bridges and other structures.
Now Hyung-Jo Jung and Seung-Woo Lee at the Korea Advanced Institute of Science and Technology in Daejeon, South Korea, plan to harness these destructive forces to generate energy. They have built a prototype that produces energy using a specific type of unstable airflow called wake galloping.
Wake galloping is a form of vigorous vibration that affects cylindrical parts of structures, such as the cables on suspension bridges, exposed to seemingly harmless airflow. When the wind passes a horizontal cylinder, eddy currents called wake vortices are created on the lee side. These induce a lifting force on a cylinder in the path of these eddies - but only if the two have the same diameter and the second cylinder is three to six diameters away from the first.
The leeward cylinder's weight counteracts the lift by pulling it back down again, resulting in the cylinder repeatedly moving up and down as the wind continues to blow. It is this movement that Jung and Lee hope to harness as energy.
To do this, they built a device containing two 85-centimetre long, 5-cm-diameter perspex rods spaced appropriately from each other. The rod on the leeward side was attached to a magnet, which was free to move within a copper coil (see diagram). As the cylinder moved, so did the magnet, generating a current in the coil.
The team found that even at wind speeds between 2.5 to 4.5 metres per second, when traditional wind turbines are inefficient, the system generated nearly half a watt of electrical power. They think this could be improved if the magnets and coils were optimised. The team report their findings in Smart Materials and Structures (DOI: 10.1088/0964-1726/20/5/055022).
"One of the most promising applications for this is monitoring a structure's health using wireless sensors," Jung says. "The device could supply the monitors with power in a bridge or a high-rise building." And if enough of the generators were grouped together, he adds, they could power a bridge's street lighting.
The pair are now attempting to find what Jung calls the "most efficient size of the device" before they attempt to commercialise it.
Jung and Lee are not alone in harnessing unusual aspects of the wind. Humdinger Wind Energy of Honolulu, Hawaii, led by founder Shawn Frayne, is interested in a similar phenomenon called aeroelastic flutter, in which aerodynamic forces reinforce a structure's natural resonance, causing it to vibrate. The most famous example of this occurred in 1940, when the newly opened Tacoma Narrows bridge in Washington state began undulating in a light breeze, earning it the nickname Galloping Gertie. Within four months of completion, the bridge had shaken itself to shreds in a storm.
Frayne has created the Windbelt, which uses aeroelastic flutter to vibrate a plastic ribbon in light to moderate breezes. The vibration moves a magnet through a coil, which generates current in a similar fashion to Jung and Lee's device.
Both will likely find a market, says Matthew Wright of the Institute of Sound and Vibration Research at the University of Southampton in the UK. "There are situations where you need a small amount of power, but in a location that's too remote to connect to the grid, or to deliver fuel or batteries to. One of these devices might well find a niche there."
On Slashdot: Harnessing the Energy of Galloping Gertie"You've all seen the footage of Galloping Gertie, the infamous Tacoma Narrows bridge. This is due to a type of turbulence called Wake Galloping, caused by airflow creating lift on the lee-side of cylinders (or cables on suspension bridges.) Now researchers in South Korea have developed a way of harnessing the turbulence to generate electricity. Their device works most efficiently at wind speeds too low for conventional wind turbines."
HGTV's latest Dream Home incorporates Control4 automation
HGTV's latest Dream Home incorporates Control4 automation
2011 HGTV Green Home includes Control4 automation, controlled by a customized iPad, and The Energy Detective monitoring system.
2011 HGTV Green Home includes Control4 automation, controlled by a customized iPad, and The Energy Detective monitoring system.
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