It is an interesting concept: while kids are playing with Lego-like bricks, composing a simple shelter, we could take advantage of the energy produced and store it.
Two critical questions are "how" and "where".
A solution could be to use the bricks as energy storage devices.
A light-weight system of springs could be responsible of absorbing vibrations and the elastic energy would be stored in a battery situated in the middle of the contructing item.
Once the brick is inserted in the proper box after having plaied, some pins will connect to the accumulator of the playground and release the energy.
Isn't it smart?
