Meet the Anker PowerHouse: a portable power supply with 12V car, AC, and USB outputs to charge your gadgets. This off-grid 400Wh power supply does not make a lot of noise. It is powerful enough to charge your laptop 15 times and a smartphone for up to 40 times.
This power supply can be charged via AC or solar. It has a smart battery management system with voltage / temperature control and safety features. Costs under $500.