Fire alarm systems need to be inspected, tested and tagged annually. Testing must include all smoke detectors, manual pull devices, annunciators, visual indicators and strobes, control units, voice/alarm communications systems and any other devices that are a part of the fire alarm system.
it will need a port like this one to get more power from the usb since it only give 5.0 volts and this powered usb give up12 to 24 volts so you dont have that in a laptop and there is no way it could raise the power on the usb port in a laptop without damaging something .http://en.wikipedia.org/wiki/Powered_USB.
1: A Standard Downstream Port (SDP) USB port can charge devices with up to 500 mA of current when the computer is on (a). However, when the computer is off (b), charging over USB is not possible. Fig. 2: The Pericom PI5USBxx is a USB charging controller.. Enabling all-the-time USB charging in PCs, laptops.