Wind up power

[DonkeyApple]

I'm thinking of building a large playhouse for the children down the end of the garden and I've been mulling over whether to install lighting etc

Obviously you can buy wind up lanterns and radios but in time they will go walk-about so I was starting to think about wiring in the kit and connecting it to a 12v generation source (via a car battery as a store). Ie the children will need to hand or foot crank a generator if they want power.

Having a long ok around for dynamos I was surprised that there don't seem to be a lot of options around?

[DonkeyApple]

Yup. Thought about solar on the roof but I fancied the idea of making them graft for their electricity. Plus, they would learn that leaving the lights on is a ball ache.

The car alternator is a good idea. I'd already thought about using an old bike as the means to convert leg power as I can envisage the handle of a hand wheel connecting with a head at some point.

The children are only 5&6 so one question is could they honestly produce enough to power LEDs and a portable radio/MP3 player without it being too much of a chore and keeping it fun?

[DonkeyApple]

MDMA . said:

DonkeyApple said:

The children are only 5&6 so one question is could they honestly produce enough to power LEDs and a portable radio/MP3 player without it being too much of a chore and keeping it fun?

sounds more Victorian workhouse than fun to me get a couple looms in there while you're at it.

Seems harsh. They have access to modern medicine for starters.

Besides, knowing my offspring they will probably arrange play dates to get kids to charge up their house for free. Thus, also teaching capitalism and labour exploitation.

Going back to the bike idea, I'm guessing the rear wheel needs to be adapted to work as a flywheel rather than a lightweight, conventional wheel?

[DonkeyApple]

roofer said:

http://www.nabendynamo.de/english/index.html

Be surprised if you can get an AC alternator to spin fast enough.

I suspect it's going to need a solar panel to keep it reasonably topped up as I don't think a winding mechanism suitable for children will do the job on its own. They seem pretty cheap but are quite ugly.

[DonkeyApple]

Dr Doofenshmirtz said:

It's a nice idea in theory - but in practice batteries need to be kept in a fully charged state to have any hope of them lasting...especially lead acid/gel/AGM. As soon as they start losing charge, the plates sulphate and the battery eventually dies.

All you need is a small solar panel on the roof (3-10 watts is ideal and no charge controller required as long as it's under 500mA charge) a 12v led strip light and a small sealed 12v 4.5 Ah battery.

Yup. But it's the child labour element that is at the heart of exploring this idea.