Superhydrophobic Coating Makes Better Solar Panels

Written by on June 2, 2015


Scientists at the Oak Ridge National Laboratory have developed a coating for glass that is superhydrophobic, making it so that it will literally bounce water off the surface. This coating also decreases the amount of light that reflects away from the glass. The benefits for solar collectors are immediately evident.

The ability to be self-cleaning would be an enormous benefit for solar panels, even without the additional conversion efficiency benefits. Although many of the best locations for solar panel farms are in dusty desert climates with very little rainfall, even there, the ability to clean the solar panels with just a small amount of water and the self-cleaning ability of the panels would be a benefit, and a savings in labor and in water use.

The coating can be applied to glass in a number of different categories, including architectural purposes, and military applications, but the use of superhydrophobic coating for solar panels could be particularly beneficial:

“Where solar panels are concerned, the suppression of reflected light translates into a 3-6 percent relative increase in light-to-electricity conversion efficiency and power output of the cells. Coupled with the superhydrophobic self-cleaning ability, this could also substantially reduce maintenance and operating costs of solar panels. In addition, the coating is highly effective at blocking ultraviolet light.”

According to the ORNL press release, the coating is also highly durable, unlike other hydrophobic and self-cleaning technologies. The process to make this coating is also cost-effective, and it “can be fabricated through industry standard techniques mak[ing] it easy and inexpensive to scale up and apply to a wide variety of glass platforms.”

via: Oak Ridge National Laboratory press release

image via: ORNL

MAR 11

Solar Impulse Begins Round-the-World Journey

Written by on March 11, 2015

Earlier this week, the Solar Impulse aircraft took off from Abu Dhabi on the first leg of it’s atempt to fly around the globe entirely on solar power.  We’ve been especially interested in this project from its beginnings as it has moved along setting new records, and we will now be watching as they make this trip around the world.

Pilots Bertrand Piccard and Andre Borschberg will not fly non-stop (which Picard did in 1999 in the Breitling Orbiter 3, completing the first non-stop trip around the world by balloon), but will fly a number of legs over several months.

The adventure is expected to last until July or August of this year, with the flight making a number of stops along the way.  The Solar Impulse site lists the proposed route with “stops in Muscat, Oman; Ahmedabad and Varanasi, India; Mandalay, Myanmar; and Chongqing and Nanjing, China. After crossing the Pacific Ocean via Hawaii, Si2 will fly across the Continental U.S.A. stopping in three locations – Phoenix, and New York City at JFK. A location in the Midwest will be decided dependent on weather conditions. After crossing the Atlantic, the final legs include a stop-over in Southern Europe or North Africa before arriving back in Abu Dhabi.”

The idea of solar powered flight seemed like a distant possibility when the Solar Impulse team announced their concept in 2007.  But work has proceeded methodically, with improvements and new records set along the way in the development of an entirely solar powered aircraft that can even fly through the dark of night solely from its stored power.  Circumnavigating the globe entirely on solar power will mark another milestone in flight, and in green technology, as well.

JAN 22

Solar-Powered Window Sensors for Smarter Buildings

Written by on January 22, 2015


Sensors are the next step needed on the road to developing smarter buildings, and a new, very-low power device has been developed to allow information about window to be transmitted to a control system for a building without a need for extra building wiring or power supply. The sensors are self-powered by the sun through a tiny solar cell on top of the unit.

The sensors, developed by the Fraunhofer Institute, are small enough to fit inside the gap between the two panes of a typical double-pane window. The solar cell itself and the sensor electronics and transmitter are so small that they sit flat on the spacer and do not block any of the visibility between the two panes.

The sensor is able to detect when a window is opened or closed, and can transmit that information wirelessly to a building management system (BMS) controlling the building. Used in conjunction with motorized operators for the windows, this can allow for a building to be opened up for fresh air when conditions permit, and to close the building back up when needed, even if the room is unoccupied.

The sensor can also serve an intrusion detection function, if the window is jostled or changes position unexpectedly. The sensor uses solar power, and is able to charge an internal battery to allow it to continue to operate even at night (currently able to span about 30 hours of darkness). Putting the sensor package between the panes also minimizes the problems that could come with occupants tampering with the sensor.

Since a single room could have many windows, the wiring to provide this level of information to a BMS system has been prohibitive in most cases. But this could be a point where a new degree of smart materials helps make a building more responsive and allow occupants a greater degree of control over their environment in conjunction with an intelligently managed building system.

image: copyright Fraunhofer Institute
via: Gizmag 

JAN 12

Who Cares About the 2015 Green Car of the Year?

Written by on January 12, 2015


One thing we’ve looked for in our annual coverage of the North American International Auto Show (NAIAS) is the attention paid to green cars. Over the past few years, we’ve noted that environmental concerns have diminished year to year. Part of this is due to those concerns going mainstream and being incorporated into manufacturers’ whole lines, to a greater or lesser extent. But the days of having a “green flagship” are pretty much over.

This year’s five finalists for Green Car of the Year were: Audi A3 TDI, BMW i3, Chevrolet Impala Bi-Fuel, Honda Fit, and VW Golf. The field is still wide open, as these include a range of fueling options, including diesel, electric, bi-fuel (gasoline/ethanol), conventional high-efficiency gasoline, and an all-of the above smorgasbord from VW with almost all of those options included in the available options for the Golf.

In fact, the VW Golf was awarded North American Car of the Year honors at this year’s show, and the new, aluminum F-150 Ford pickup won for Truck of the Year. But none of the manufacturers has a display touting the Green Car of the Year. Senior representatives for a couple of the contenders knew that it wasn’t one of theirs, but didn’t know beyond that. The Green Car of the Year seems to have fallen off general awareness at this year’s show.

The most striking new technology on display, which will be of interest to green car enthusiasts, are hydrogen fuel cell vehicles (FCVs). These are going to be the next big thing to watch for, and a number of manufacturers are displaying their FCV concepts and demonstrators. Companies with FCVs in their displays this year include Honda, Hyundai, and Toyota.

Fabrication and 3d printing are also concepts getting prominent display at this year’s show. An operational 3D printing station is on the main floor as part of the Local Motors display, printing out a car body during the show. The lower level of the show, which often has some of the more interesting displays, has a complete 3D printed car, as well as probably the least fuel efficient vehicle at this year’s show, a Bradley Fighting Vehicle (not for retail sale).

Informative static graphic displays are also in much less abundance than previous years. The engine-on-a-stick motif and the cutaway display are much less a part of this year’s show. Many of the manufacturers seem to be focusing more on the sculpture and the simple presence of their cars. Displays about fuel efficiency or milage are in very short supply at this year’s show. And no one is trying to show off a particular vehicle as an esepcially green leader.

If you’ve read this far, then you, too, must have some interest in green cars. Since the announcement was made a few weeks ago, maybe it’s not considered news. But it seems emblematic of just how far things have gone – whether you see that as a good thing or a bad thing – that it’s not even a part of BMW’s display for the vehicle to announce that the BMW i3 is this year’s Green Car of the Year.

DEC 12

Solar-Powered, Concrete Hull Boat

Written by on December 12, 2014


Carter Quillen is an engineer who bought an old, concrete hulled sail boat named the ‘Archimedes’ and, instead of refitting it with new masts, decided instead to turn it into the largest solar powered concrete hulled boat in the world.

The ‘Archimedes’ is a 50 feet (15.24 meters) long, with a displacement of 20 tons and is able to travel at up to 5 miles per hour (8 km/hour) powered solely by a 5kW solar array. Quillen is traveling along the Intercoastal Waterway as an advocate for microgrid energy production as well as using his boat as a demonstration platform for sustainable technology.

In addition to solar electric propulsion, the ‘Archimedes’ also uses solar power for its refrigeration, A/C, and water heating, and the solar panels are also being developed to be deployed in a funnel configuration for rainwater catchment.

Quillen is also campaigning for greater use of solar power in Florida, noting that “the ‘Sunshine State,’ ranks 20th nationwide in solar energy use per capita.”

Link: Ship of Imagination

video link


Is BEHA the Greenest Plane, or a Kitchen Sink?

Written by on December 5, 2014

Most people thought the triplane was a relic of the past, an ungainly aircraft from the early days, left behind as more modern designs came to the fore.  But the triplane could be getting another lease on life if the Kickstarter campaign by Faradair Aerospace Limited is successful.

The BEHA (which stands for Bio-Electric Hybrid Aircraft) is an odd looking design which seems to have everything but the kitchen sink thrown at it.  The design is intended to be a six-seat aircraft with “sports car feel,” with an emphasis on safety.  The cabin is intended to have Formula 1 style crash protection as well as a ballistic parachute recovery fail-safe system.  The electric fans and ducted propeller, along with the lift from three wings, are intended to provide for exceptionally quiet flight.

Bio-Electric Hybrid refers to the combination of propulsion systems being used.  This project combines a biodiesel engine (to generate electricity and to run a large ducted pusher propeller at the back) along with twin electric fan motors.  The plane will take off and land using the electric motors, and the biodiesel engine and pusher propeller are for in-flight recharging and aiding in cross-country cruising.

But wait, like the late-night commercials say, There’s More!

The triple wing provides greater lift for the plane.  It also provides more top surface area for solar panels.  Yes, this plane also has solar panels on all three wings, as well as the fuselage and on top of the duct surrounding the pusher propeller in back.  The solar panels “are not the primary power source for the electric motors, but simply additional trickle charge capability.”

Does all of this unusual gear really make it a green aircraft?  Lots of aircraft have tested biofuels, and the performance has been pretty much uniformly acceptable.  Solar panels on the wings are part of the Solar Impulse, but that is a very specialized, purpose-built craft that does use its solar panels to power the craft.  Ducted fans and electric engines are being used in other applications.  Even whole-airplane parachutes are not new.  Does putting all these features together make a very green vehicle, or is it just a rough patchwork of other concepts all put together in a single vehicle?

EcoGeeks like us have been intrigued by a host of other unusual aircraft concepts over the years. Certainly other pioneering vehicles seemed ungainly at first.  Whether the BEHA rises to become a star will remain to be seen.

Link: Faradair Kickstarter

NOV 26

Super-Efficient Solar Water Desalination

Written by on November 26, 2014


A novel approach to desalinating water could be very beneficial in providing fresh water for many parts of the world needing clean water.  This is a relatively inexpensive process which uses graphite to use solar energy far more efficiently than ever before.

Desalination is an important way to provide fresh water in many parts of the world, but it is usually an extremely energy intensive process.  In order to produce fresh water, the brackish water must be heated to produce steam, which leaves the salts behind.  Then, the steam is condensed to yield clean water.

Solar power would seem to be ideal for this application, but, until now, it has required intense concentration of sunlight in order to produce the heat needed to boil the water.

The method developed by Dr. Hadi Ghasemi at the University of Houston first microwaves graphite for a few seconds, causing it to fracture and pop “like popcorn.”  This material floats on top of a container of water and draws small amounts of water up through capillary action.  The pores in the material serve to further concentrate solar energy on those small amounts of water, causing it to steam.  Since the solar energy is concentrated on just the top layer, the rest of the water stays cool, so far less energy is needed to produce the steam.

This allows cheaper and simpler equipment to be used to concentrate the solar energy and makes for a simpler system to produce clean water.  And graphite is a cheap and plentiful material, which also makes this a promising technology.

via: BoingBoing and NPR

NOV 25

Better Cement for Construction with Less CO2

Written by on November 25, 2014


Greener cement for construction may be already well within reach, based on a new study carried out by researchers from MIT in the United States and CNRS in France.  While modern-day cement has its roots extending back to the mid-1700s, the ratios of the two main ingredients, calcium (from limestone) and silica (from clay), which are used to manufacture it can vary widely, and had not been studied to this extent before.

The potential reduction in carbon emissions from the production of cement could be as much as 60 percent, according to Dr. Roland Pellenq, the senior research scientist for the study.  The production of cement is presently one of the largest contributing industrial sources of CO2 in the atmosphere.  Consequently, changes in its manufacture could have significant and widespread benefits if a better production method is developed.

“In conventional cements, Pellenq explains, the calcium-to-silica ratio ranges anywhere from about 1.2 to 2.2, with 1.7 accepted as the standard. But the resulting molecular structures have never been compared in detail. Pellenq and his colleagues built a database of all these chemical formulations, finding that the optimum mixture was not the one typically used today, but rather a ratio of about 1.5.”  Production of cement at this ratio would, according to the researchers, allow significant reductions in CO2 emissions.  In addition to the emissions benefit, the researchers also found that cement produced at this ratio would be stronger and more fracture resistant.

Adaptation of this research will still take time to implement, as the new formulations will need to be studied by engineering standards organizations before this becomes the new standard for manufacture.

There could even be a synergistic benefit in this, by significantly reducing the carbon emissions in the production of the cement, and then further reducing emissions due to less cement being needed due to the improved strength of the material.

via: MIT Press Release

image credit: Phlat Phield Photos

NOV 23

Electric Turbochargers to Improve Engine Efficiency

Written by on November 23, 2014

In the ongoing quest to improve, electrically powered turbochargers may be the next step in increasing engine efficiency for automobile engines.  The first such to be included in a production model is slated to come in 2016 from Audi on its SQ7 SUV.

Turbo boost has been a popular way of increasing the power of an engine without increasing its size.   Ford’s EcoBoost is an example of this approach, using 3-, 4-, and 6-cylinder engines in vehicles which had previously used larger engines.  Turbocharging an engine increases the amount of air, and therefore fuel, being fed into the engine, providing better performance from a smaller-sized engine.

Conventional turbos use exhaust gasses to spin the turbine that forces more air into the engine.  This is efficient, but it produces “turbo lag” as the engine needs to increase speed in order to develop the boost.  But an electric turbo can respond almost instantaneously, providing added power without any delay.  Furthermore, as Green Car Reports notes, “a more responsive turbo will help the engine produce more low-end power, meaning drivers won’t have to venture higher into the rev range–and increase fuel consumption–as much.”

This becomes a more viable option with the increased computerization of engine control systems, which can read the driving conditions and trigger small amounts of boost as needed.

Whichever kind of turbo is used, the benefits come from having a smaller engine, both in terms of the overall displacement of the cylinders, as well as the mass of the engine itself.  Smaller engines mean less weight the car has to move, which helps in efficiency.  And the smaller displacement means less fuel is routinely used, while the power that would have been available is still there, thanks to the boost of the turbo.

via:  Gas 2.0

image credit: Wikipedia/NASA


Nobel Prize Awarded for Blue LEDs

Written by on October 7, 2014

The Nobel Prize in physics this year has been awarded to three scientists, Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura, for their work in the development of the blue LED.

LEDs were first developed in the early 20th Century, and the first practical, commercial LEDs were brought to the market in the 1960s.  However, the earliest LEDs were red or orange.  The development of blue LEDs was crucial to the ability to make “white light” LEDs, which combine blue, green, and red (or sometimes blue and yellow) to create an acceptable light source for general illumination.  The high efficiency of LED light bulbs and LED displays which we enjoy today stems from this research work.

As the Nobel committee noted, “As about one fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth’s resources.”  With the increased use of LEDs for lighting, demand for electricity is reduced.  We salute these three as EcoGeeks of the highest order.

link: Nobel Foundation Press Release

image: CC BY-SA 3.0 by Gussisaurio/Wikimedia Commons