What happens when a cruise ship loses power after boat left stranded for hours

If you've seen Netflix's Poop Cruise documentary, you'll know its never good news when a cruise ship loses its power.

Just this weekend, passengers on board a Celebrity Cruises vessel nearly saw their luxury holiday turn into a disaster due to a loss of power.

The ship, Constellation, was forced to drift for around three hours while sailing near the Italian coast on August 2, and was said to be without power or air conditioning for just under three hours.

Royal Caribbean, Celebrity Cruises' parent company, confirmed the vessel had experienced a 'technical issue' that was resolved later that day.

But while this cruise managed to fix the issue onboard fairly swiftly, you might be left wondering what would happen if you found yourself on board a cruise with no power.

The Constellation vessel was adrift for around three hours (Tim Boyle/Bloomberg via Getty Images)

What happens during a power cut

While it depends what is the cause of the loss of power, the most immediate effect would usually be a loss of propulsion.

This means that, like the Celebrity Cruises ship, the vessel will likely stop moving and be left to drift while the cause of the power loss is resolved.

Again, like what happened on the Constellation, many of the interior lights will likely go out, especially in cabins and hallways, and air conditioning may be affected too.

Lifts will usually be out of action, primarily as a safety measure, to prevent them from stopping working while passengers are inside.

Meanwhile, the bridge could lose radar, GPS and communication tools, although it will likely be able to rely on backup systems during this time.

As Poop Cruise highlighted, toilet and fresh water systems could stop working as they rely on electrical pumps.

The ship's emergency generator kicked in (Tim Boyle/Bloomberg via Getty Images)

Emergency power systems

Fortunately, most cruise ships are equipped with emergency generators, which will prioritise the most important functions required while the main power sources are restored.

These generators will usually maintain power to critical systems, like emergency lighting and bridge controls, while allowing the captain to sustain contact with the coast guard and port authorities.

The emergency power will also support basic medical equipment and run essential navigation systems.

Netflix recently released a documentary on the 2013 'Poop Cruise' (Netflix)

In the case of the Celebrity Cruises ship, Royal Caribbean has confirmed these emergency generators, which are located on the upper decks, will automatically kick in using an independent fuel source.

The infamous Poop Cruise blackout was caused by a fire in the engine room, which prompted the cruise line, Carnival Cruises, to invest more than $500 million on fleet upgrades, including backup generators and fire suppression tools.

In short, the cruise line has ensured no one will ever have to defecate into a red bag on one of its cruises ever again.