Mrs Green has been pootling around the inter-webby learning about experimental battery storage technology.
On our journey we discovered, via Great Green Gadgets, a clever little clock that is powered by a battery that uses ordinary tap water.
According to Hammacher Schlemmer this little time-keeper can be powered for up to 12 weeks before needing a re-fill. Sadly, it seems that they are no longer selling it. Taking time-out perhaps?
Thousand Suns has produced a portable solar generator packaged in a flight-case.
Unclip, fold out and position the solar panel using the fold-out legs and it will charge fully in six hours. The unit can also be charged using a mains charger in about four hours.
EnviroGadget has plenty more information and pictures of this sleek 4.1 kg solution to powering phones and fridges among other things. Mrs Green is also happy to read that the battery is 95% recyclable and has a life of about 10 years.