Ideas are popping out of the woodwork now that aviation is beginning to understand the threat global warm-gaming* poses to its reputation and livelihood. The latest has been published in the UK Institute of Physics' journal Superconductor Science and Technology, where researchers say the technology is available to build a non-polluting all-electric aircraft using superconducting motors for propulsion and actuation and liquid hydrogen for cryogenic cooling and power generation. High-temperature superconducting motors would replace the gas-turbine cores in the aircraft's high-bypass turbofans, and be driven by electrical power produced from the hydrogen through fuel cells or by burning it in high-speed turbogenerators.
The propulsion and power system for an all-electric Boeing 737 would be heavier, but the fuel required would be less, researchers estimate. You can read read the report here.
*Woracle definition – global warm-gaming: exploiting public fear of climate change to further personal ambitions.