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.
The USB battery charging standard defines two types of ports: Charging ports, and regular data ports (and combi ports). A charging port is one that supplies >500mA@5V, but can't do data. A charging port is indicated to the device by a short between the D+/D- lines. QC aside, there's no digital data communication.