100 Percent Efficiency? Great! and So What?

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

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 …

The New Mythbusters: Slow Charging May Not Make Batteries Last Longer

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

For the last 60 years, your editor remembers the oft-repeated advice from garage mechanics and now lithium-ion advocates that slow charging is the way to make your batteries last for many cycles.  Where does this put Tesla, for instance, with its 20-minute Superchargers?  Are you damaging your expensive cells by being in a hurry? In yet another example of counter-intuitive thinking at work, researchers at SLAC, the National Accelerator Laboratory at located on the Stanford University campus have challenged several tenets of conventional battery wisdom.  According to PC World, their work, “published on Sunday in the Journal, Nature Materials, challenges the commonly held notion that slowly charging a battery helps prolong its life and that it’s damaging to a battery …