Still on the broad subject of energy, I came across this interesting design that claims to produce hydrogen at 15% efficiency using sunlight!
'Scientists at KU Leuven in Belgium have developed a device that combines incoming solar energy and water vapor from the surrounding air to produce a record-breaking daily average of 250 liters (66 gal) of hydrogen throughout the year. According to the researchers' estimations, an array of 20 such panels paired with an underground pressurized tank could provide the totality of a household's entire electricity and heating needs for a modest price.'
If this pans out it could be a very practical way to run small scale energy production, as small scale as running one's house and car!
Mike