Simply extend the script a little , something like this:

var power = 0;
var pwrdown = 0;

while (power < 100)&& (pwrdown == 0)
{
//do your stuff;
power += TIME;
....
}else
{
//do your stuff;
pwrdown=1;
power -= time*0.25;
}

Hope it helps

Trash

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program (pro'-gram) A magic spell cast over a computer allowing it to turn input into error messages.