Don’t Smoke ‘Em Even if You’ve Got ‘Em

Dean Sigler Biofuels, Diesel Powerplants, Sustainable Aviation Leave a Comment

Biofuels would be wonderful if they didn’t starve people while feeding trucks, cars and airplanes.  Living with such a constraint, though, might prove to be productive, profitable, and environmentally sound. The Guardian describes efforts in America’s tobacco country to grow a crop that will be less destructive of human lungs and hearts if it is consumed in jet engines rather than in cigarettes. “’We’re experimenting with varieties that were discarded 50 years ago by traditional tobacco growers because the flavors were poor or the plants didn’t have enough nicotine,’ explains Tyton [BioEnergy Systems] co-founder Peter Majeranowski.” In a case that oddly enough is GMO free, “Researchers are pioneering selective breeding techniques and genetic engineering to increase tobacco’s sugar and seed oil content to create a promising source of renewable fuel. The low-nicotine varieties require little maintenance, are inexpensive to grow and thrive where other crops would fail.” Fuel tobacco is a higher-value crop than hay, for instance, and “looser” farming …

Airliners Get Better Mileage than Cars, and Trains do Even Better

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

Airliners beat cars in fuel economy, especially on longer trips.  That would not be news to attendees at recent Electric Aircraft Symposia, where speakers like Ilan Kroo, Stanford University professor and aircraft designer, have brought that message home. One of Kroo’s slides, shown below in a 2009 lecture (It’s nearly an hour, but worth a look and listen), lists a “narrow-body” airliner (in this case a Boeing 737-800) as able to fly one passenger coast-to-coast on 29 gallons of fuel, at about 81 passenger miles per gallon.  A person carpooling his or her four-passenger Prius and driving responsibly could beat that (although not in the five hours required for the jet to make the total flight), but most trips are solo affairs, especially during commutes. Not anywhere near Green Flight Challenge efficiencies (403.5 ppmg for the winning Pipistrel G-4), such economies are improving with more modern versions of fuel efficient airliners.  Cars are also gaining in fuel economy, prompted by government …