Hello Philippa and Georgina and Jo Jo and Sarah and to others who I can’t remember.
The following are the links I said I would post which are related to your projects:
Charging while walking:
It’s worthwhile looking at how this motion produces electricity:
This one involves usual solar power
All you need for this one is 500 lb of potato
Not sure if this is possible either – but we can test!
Onion and ipod
Looks like this may be a fake, but how can we tell . . .?
(not so) constructive comments:
Heat from Manure
Not too much out there, but at least it seems to have been done before:
Good luck, and keep me informed.