The Okeanos Explorer is diesel electric, using four very large diesel engines that put out 600 kilowatts of electricity each. This electricity is used to power the ship and the two main propulsion motors that turn the props moving the ship through the water at speeds of up to 10 knots. Two of these diesel engines are received their 40,000-hour overhaul during dry dock. Download larger version (jpg, 6.2 MB).