Laptops that can charge battery via typing on keyboard. Think bicycle generator.
User will expend energy to type. This energy can go towards charging battery.
This method would no completely recharge the battery of course. However much like hybrid cars using braking, it would recharge the battery partially and extend the life.
Seems to me like you'd either have to make typing on this thing a horrible chore, or you'd be increasing the cost of the use exponentially for almost no battery life improvement. With a coil and a magnet on every key you COULD generate power, but we're talking so little it'd be stupid to waste the energy producing the coils and magnets.
To make this work you should use piezoelectric generator cells. They use they on dance floors and bridges to generate electricity from compressing and and decompressing a crystal lattice. just look up piezoelectricity. basically a grill lighter under every key
Considering that riding my exercise bike at a simulated 30km per hour on "medium resistance" only generates 60Watts (about the power usage of a laptop - check the AC adaptor label), the contribution from finger power during typing is going to be negligible. Back to the drawing board... .
This method would no completely recharge the battery of course. However much like hybrid cars using braking, it would recharge the battery partially and extend the life.
If you could get enough energy from the keyboard, the whole thing would run for months on a single AA battery.
Seems to me like you'd either have to make typing on this thing a horrible chore, or you'd be increasing the cost of the use exponentially for almost no battery life improvement. With a coil and a magnet on every key you COULD generate power, but we're talking so little it'd be stupid to waste the energy producing the coils and magnets.
To make this work you should use piezoelectric generator cells. They use they on dance floors and bridges to generate electricity from compressing and and decompressing a crystal lattice. just look up piezoelectricity. basically a grill lighter under every key
Considering that riding my exercise bike at a simulated 30km per hour on "medium resistance" only generates 60Watts (about the power usage of a laptop - check the AC adaptor label), the contribution from finger power during typing is going to be negligible. Back to the drawing board... .