Their ships were able to cross the galaxy in a matter of days with almost no external power.

Rather, they kept a firm hand on such external powers.

The system, which can produce electricity from sunlight, needs external power to operate.

A moment later external power was attached to the aircraft and the interior lights came back on as well.

This version had a built in light organ, with an external power supply.

Both can continue as long as the source of external power is present.

Independence in the terms of external power and water supply sources loss.

Some devices require internal or external power to maintain stored information.

However, it can be connected to external power when available.

No external power could destroy national traditions which were rooted in centuries of history.