Right now few cars have LED (light-emitting diode) headlights, but more will come, he said.

This would be enough to power an electronic speaker or small LED (light-emitting diode) lights, but not enough to operate a laptop, which requires an estimated 30 to 50 watts.

This article examines data logging of temperature using the TMP36 temperature sensor and a simple light-emitting diode (LED) for light.