Fuel efficiency

An innovative new combustion engine eliminates half the guts of a traditional engine, and uses a fascinating internally rotating piston and sleeve arrangement, making it lighter, simpler and more efficient while still making strong power and torque.

Kenworth has unveiled a sleek-looking SuperTruck 2 at the Advanced Clean Transport expo in Las Vegas, attempting to squeeze the maximum possible efficiency out of a diesel powertrain. It works, too, beating the company's most efficient truck by 100%.

That's without any modification to the ships themselves, too. The ambitious 'Blue Visby Solution' proposes enormous fuel and emissions savings for cargo ships worldwide, simply by being smarter about speed and timing and eliminating inefficiencies.

A West Texas company says it's found a remarkably simple way to slash air cargo costs as much as 65% – by having planes tow autonomous, cargo-carrying gliders behind them, big enough to double, or potentially triple their payload capacity.

A futuristic-looking electric vehicle that was launched way back in 2007 is finally on the road to production. Following a year-long crowdfunding effort, the first 2,000 Aptera Launch Edition solar EV production slots have now been taken.

Range Energy makes truck trailers, with a clever connection to any standard tractor cab, loaded with electric powertrains to turn any semi into an efficient hybrid. They also let you push entire trailers around by hand at the depot in "shopping cart mode."

GE once thought super-efficient propfans were the future of air travel, until low fuel prices in the late 1980s moved fuel consumption down the list of priorities. Now, it's bringing them back with the CFM Rise, promising 20% fuel savings.

With a US$425-million cash injection from NASA, Boeing will build and test a full-sized airliner based on its transonic truss-braced wing (TTBW) concept, using long, thin, strut-braced wings to add lift, reduce drag, and burn an impressive 30% less fuel.

The Celera 500L is a truly remarkable design. Otto Aviation says its odd shape delivers an astonishing 59% reduction in drag, so it can cruise as fast as a small jet while using 80% less fuel. Now, Otto and ZeroAvia are giving it a clean powertrain.

Zero-emissions airliners are still a long way off, but Lufthansa and BASF have developed a way to improve things right now. AeroShark is an adhesive riblet film that immediately reduces fuel consumption, and therefore emissions, from any aircraft.

French company Airseas has installed its first half-size automated Seawing kite to a cargo ship chartered by Airbus, and will commence six months of trials in January. The full-size kite is estimated to save up to 20 percent of fuel burn and emissions.

Ordinarily, airliners have to run their engines in order to taxi along the runway – this uses a lot of fuel, plus it generates a lot of CO2. A new in-ground towing system, however, offers what could be a more efficient and eco-friendly alternative.