Living Up To a Standard

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Ron Gremban is an early developer of plug-in electric hybrid (PHEV) automobiles, having helped convert hundreds of Toyota Priuses to extend their electric-only range and make them even more practical real-world automobiles. His 2008 writing on the differences between the Prius and Chevrolet’s Volt shows an ability to consider the actual physics and engineering involved rather than allowing the heat of the debate to obscure the realities. Backing from Dr. Andrew Frank of UC Davis gives further credibility to Gremban’s views. Given his demonstrated abilities and his dispassionate vision, it’s no surprise that Gremban would look at projected electric flight in ways that haven’t yet occurred to its most ardent promoters. On April 27, at the Friday evening Motors theme dinner, as part of the Electric Aircraft Symposium hosted by the CAFE Foundation, he shared some of his concerns about potential safety concerns for electrified flight. For instance, how do pilots and know that an electrically-powered propeller is “on” or activated …

No Pain in This Membrane

Dean Sigler Electric Powerplants, Sustainable Aviation 9 Comments

On September 30, the National University of Singapore announced the world’s first energy-storage membrane, with the claim that it “outstrips existing rechargeable batteries and supercapacitors,” and according to Science Daily, “Surpasses existing rechargeable batteries and supercapacitors.” The cheese-cloth appearance looks a bit like a gauze bandage, but when sandwiched between what are alternatively described as two thin metal plates or two graphite plates can hold a significant charge much greater than that of conventional batteries or supercapacitors. The material, developed by a team from the National University of Singapore’s Nanoscience and Nanotechnology Initiative (NUSNNI), and led by principle investigator Dr Xie Xian Ning, is capable of holding a “charge at 0.2 farads per square centimeter. This is well above the typical upper limit of 1 microfarad per square centimeter for a standard capacitor,” according to the University. Because energy storage in capacitors is usually measured in farads, How Stuff Works calculates the following to help us understand what that means …

Combining the Best of Batteries and Supercapacitors

Dean Sigler Electric Powerplants, Sustainable Aviation 1 Comment

The CAFE Blog has been tracking developments in batteries and supercapacitors for nearly the last two years, and the annual Electric Aircraft Symposia have attracted speakers on a wide range of innovations in these areas.  Gizmag reminded us this week how much all of this may soon affect the ability of energy storage and power devices to change our world. Their report highlighted work on an energy storage system that combines the energy capacity of batteries with the power density and quick recharging capabilities of capacitors being done at Rice University, and linked that to research at the University of Illinois by Dr. Paul Braun on creating faster charging batteries with higher energy densities than currently possible.  Gizmag then did a callback to something covered earlier by CAFE, the use of structural panels in electric vehicles as energy storage devices. Both researchers pointed to the big disappointment in electrical devices – batteries.  They are either short-lived in their application or take …

CAFE News: Comparing Apples, Bananas, Oranges and Doughnuts

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation Leave a Comment

One of the problems facing judges in the July Green Flight Challenge the CAFE Foundation is managing for NASA is that of determining fairly who gets the best fuel mileage.  Since “fuel” in this case can be traditional aviation gasoline, bio-diesel, electricity from batteries or solar panels, or some other energy storage medium, wildly different energy densities have to be taken into account. If TSA “freedom feels” seem intrusive, the scrutiny applied to GFC entrants and their craft will be even more onerous.  Aircraft will be impounded once inspected and registered, and the only contact pilots may have with their planes before taking off will be to “top off” their fuel tanks or batteries just before the start of their flight – all under constant monitoring. The widely and wildly differing energy densities for the different forms of motive power require careful definition of energy equivalencies.  One pound of gasoline, for instance, equals about 20,000 BTU, or 5.8 kilowatt hours, …

Solar Impulse All-Nighter July 1

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Solar Impulse is set to attempt its first night flight on Thursday, July 1, 2010. Weather conditions are “Favourable for attempting the first night flight on solar energy,” according to the Solar Impulse web site.   “The situation continues to look good and the likelihood of seeing the HB-SIA take off on July 1st and land back in the early morning 2nd July is increasingly probable.” The Solar Impulse team will confirm the date 24 hours before take-off time.  Only accredited journalists will be allowed on-site to witness the event, so don’t head for the Payerne, Switzerland airbase, but follow the flights on the Internet at the project’s special Night Flight web page at www.solarimpulse.com. These flights are crucial to the ongoing aim of flying a solo mission around the world in five hops, followed by the development of a two-seat version of the airplane that will enable a non-stop, around-the world solar flight.  This will hinge on the ability of the craft’s over …

Solar Flight at Night

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

The Solar Impulse prototype, HB-SIA, will be making its first night flights within the next month, according to a June 15, 2010 press release from the project team. With eight successful flights to its credit, the airplane will attempt two critical missions according to the release: “the first night flight ever by a solar aircraft “the first ever complete cycle flight to validate the possibility of long-duration flights without any fuel” “’To fly day and night with a solar aircraft is a human and technological challenge that has never been met so far, and an essential stage of the project’, says André Borschberg, CEO and co-founder of Solar Impulse. ‘Demonstrating that we can fly a whole day and night will then permit us to fly several successive cycles and come close to perpetual flight.’ “’The big question will be whether the pilot will be able to save sufficient energy as to fly right through the night. These night flights in …

Overcome Inertia, Read About Enertia

Dean Sigler Electric Powerplants Leave a Comment

David Bettencourt, an eagle-eyed legal eagle in Hawaii, prompted me to pick up a copy of the April, 2010 Cycle World magazine, in which two articles advance the cause of electric transport.  The first,”Brammo Enertia”, is a critique of the electric cycle that you can buy at Best Buy.  It details the long-term interest of company founder Craig Bramscher in electric vehicles, and his analysis that a vehicle with sufficient range for today’s suburbanite, based on normal commuting needs and available technology, would have two wheels – hence the Enertia.  Matthew Miles, author of the piece, does a good job of comparing performance with a 250-cc Kawasaki Ninja.  Although the Enertia is no match for the IC-powered machine in off-the-line sprints or top speed, it wins the economy-of-operation cup. (Cycle World’s web site has the added bonus of an interview with Craig Bramscher.) The second article, “Batteries Heat Up” is by Bettencourt’s favorite technical writer, Kevin Cameron.  It’s easy to see why Bettencourt collects Cameron’s articles, since …

EAS IV is Your Ticket to an Electric Aircraft Future

Dean Sigler Electric Powerplants Leave a Comment

This press release from the CAFE Foundation speaks for itself. The fourth symposium of its kind is an international, multidiscipline gathering which will  influence the very future of aviation. Santa Rosa, CA., Mar. 1, 2010 – The Comparative Aircraft Flight Efficiency (CAFE) Foundation’s 4th Annual Electric Aircraft Symposium (EAS IV) will convene a renowned faculty of experts on electric aircraft technologies on April 23-24, 2010, at the Doubletree Inn in Rohnert Park, California. The networking program will consist of presentations and exhibits on bio-fuel hybrids, advanced electric motors, solar panels, sailplane technology, fuel cells, future technology for batteries, battery safety during charging, propeller noise reduction, autonomous flight controls, drag reduction, vertical takeoff designs and NASA’s Green Flight Challenge competition. Each presentation will be followed by a Q&A session with the audience, which will be comprised of government officials, enthusiasts, designers, entrepreneurs, students and media. The debut of some exciting new designs is expected at this year’s meeting. Among the outstanding …