On Thu, 19 Jul 2012, aesthete8 wrote:
> Is there such a thing?
>
Why?
Unless you sit on it or put books on it, it draws very little current,
maybe none at all, when it's just sitting there. Pressing a button uses
current, but it's a brief instance. The batteries may last almost as long
as if you just left them on the shelf.
Given that, any fidgetting is going to bring up the cost. You could use
rechargeable batteries, but then you'd need to keep recharging them, since
they self-drain. Add solar cells to charge the battery? But the
batteries last long enough. Add a crank generator to charge up the
batteries? But the batteries last long enough. You end up spending money
on a problem that isn't a problem.
SOmething like a flashlight makes sense, since it draws steady current
when on, and likely goes long periods without use. You want that
flashlight to work when the power goes off, hence it makes sense to have a
crank generator or a solar cell to keep it charged. But the circumstances
are different.
Michael