A portable oxygen concentrator can run on both AC and DC power, and the batteries can be charged with both. This battery charge allows it to bring in air and separate the oxygen from the rest of the air, for you to breathe in on the correct setting. Some portable oxygen concentrators offer both continuous flows and pulse dose settings.
A home or stationary oxygen concentrator runs on AC power only. It brings air through the inlet vent, and it runs through a filter, which catches dust and other small foreign particles. The oxygen is separated from the rest of the air, which is expelled out of the machine through a different vent. The oxygen is then released through the tube and cannula in the proper dosage.