One of the easiest and yet largest changes would probably be to shift cars and other vehicles from a generate on-board model to a model where energy is stored i

One of the easiest and yet largest changes would probably be to shift cars and other vehicles from a generate on-board model to a model where energy is stored in the vehicle but is generated in a more centralized manner. Centralizing energy production enables better scaling (small ICEs are on average much less efficient than large ones), reduces the cost of deploying new technologies as they become available, enables depending on local opportunities for renewable energy, etc. There are many good proposals for how to store energy in-vehicle, such as capacitors, batteries, flywheels, fuel cells and even pneumatic storage. There's many good business opportunities to be had exploring these options and bringing them to market. See, for example, Tesla Motors and the Chevy Volt. There's a lot of startups doing good work in this field, including one founded by a HN regular DaniFong: http://lightsailenergy.com/ http://lightsailenergy.com/ As time goes on, I think we'll see an explosion in this area, but only if we as a society place the proper emphasis on tacking the problem.