100 Percent Efficiency? Great! and So What?

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

A particularly brilliant and demanding manager for whom your editor used to work had a “SO WHAT?” stamp with which he would critique our technical papers and proposals.  His point in defacing our papers was not to be snide, but to force us to defend why we included certain facts – interesting though they may be in themselves. Two different and equally brilliant discoveries by University of Cambridge and University of California, Riverside researchers bring the “so what?” stamp to mind.  Even with their breakthroughs, approaching 100-percent efficient solar cells in the first instance, solar cells may not yet be a perfect fit for aircraft propulsion. Each square foot of the earth’s surface receives about 15 Watts of solar energy during a bright day.  100 square feet of solar cells (about what we could expect for an average-size wing on an average light plane) would see 1.5 kilowatts hitting that surface – not enough to sustain flight on anything but …

Replacing Gasoline with Aluminum?

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

Several researchers in commercial, government, and academic realms are studying the possibility of using aluminum as an energy source for vehicles and even grid power. In the commercial realm, Alchemy Research in Israel makes the following rather startling claims.  “Alydro is a new technology developed by Alchemy Research for producing clean energy from a reaction of aluminum and water at elevated temperatures. “Alydro generates energy in the form of hydrogen and heat. The only by-product is fully recyclable aluminum oxide. “Alydro is competitive with gasoline on energy density and affordability. It is superior to gasoline on sustainability, environmental characteristics and safety.” Alchemy Research claims that aluminum has 2.5 times the energy density of gasoline, about 84 mega Joules per liter or 23.3 kilowatt hours. Aluminum has about 8.6 kilowatt hours per kilogram, considerably more energy dense than lithium batteries, which range from 120 to 190 Watt-hours per kilogram. Storage takes less space than its equivalent in gasoline and the material is perfectly …