deep sea oil rigs

I was watching a show on deep sea oil rigs. Amazing stuff.
I was wondering about the electricity they use. Now, I know that they have generators, but it seems like these rigs would be a good place for air or water powered generators to help produce electricity.
Do any of you guys know anything about this?

By “air or water powered,” I assume you’re talking about wind turbines or water turbines, correct? Neither of these reliably works 24/7, so you would need some kind of on-site energy storage system or conventional fossil-fuel power plant to provide electrical power during periods of inadequate wind or water currents. It would be difficult/expensive to build adequate on-site energy storage to get you through the doldrums, which means the only option is a fossil-fuel power plant big enough to meet 100% of the rig’s electrical power demands. And if you’re already installing a fossil-fuel power plant big enough run the place, then it’s probably cheaper to just run it 24/7 than it is to install/maintain a wind/water turbine and manage the switching back and forth between systems.

Yeah, I was thinking of turbines. The show I saw was on the " North Sea" and there seemed to be a lot of wind and waves to generate electricity.
I wasn’t thinking of storing it as much as using the turbines to supplement what they are using at the moment.
I know that the wind or waves can be too much for the turbines and I don’t know how much it would cost to do this. I was just wondering.

Those rigs are huge and use a lot of electricity, you’d need a substantial wind/wave farm to even put a dent in their consumption. Probably as much infrastructure dedicated to generating electricity as dedicated to drilling wells, so equivalently two rigs expenditure instead of one.

And let’s face it - these guys make their money off of fossil fuels. “Going Green” isn’t a top priority at least in the drilling phase.

On drilling rigs they need to be completely mobile and they use large amounts of power so generators aboard is really the only option. You are talking about a drilling package that has to move around 2 million lbs hook weight and provide rotary power plus power the mud pumps so not trivial.

On production platforms, that can have derricks aboard too for production drilling and workovers of existing wells, they are increasingly hooked up to power supplies from nearby platforms and sometimes (and increasingly) from the beach. Onshore power is more reliable, cheaper and greener.

Until the oil price crash STATOIL were looking at putting in a sub-sea power grid into the Norwegian sector of the North Sea, so that any production platform could hook up to it (and potentially drilling rigs too). All to be powered by the onshore electricity grid. It was going to cost billions so I suspect that has been kicked into the long grass now.

I’m a former petroleum geologist and use to work on drilling rigs from back in the 80’s by the way if you wonder about my credentials for all this.

What is the procedure for getting the oil from the rigs on to the boat tankers? How often do the oil rigs need to be refueled so that they can keep running?

Well, I think I need to say something about terminology I’m afraid…

In the oil patch rigs are for drilling wells and platforms are for producing oil from completed wells. Generally if a drilling rig finds oil they either test it and plug/abandon it or suspend the well for incorporation into future production (from a platform).

So, generally, oil is not produced from rigs. Sometimes they can do extended well tests when it has to moved to storage - they generally use FSOs (floating storage and offtake) facilities that themselves allow shuttle tankers to remove the oil or in the Gulf I believe sometimes simple oil barges if in shallow water.

Keeping the drilling rigs drilling needs supplies of various sorts and how often depends if you are talking about jack-up rigs, semi-submersible rigs or drill ships. The first two need regular supply vessels to deliver mud chemicals and tubulars etc, the latter can be largely self supplied.

It is hard to keep this simple but also accurate. :slight_smile:

What karpov said. In addition Drilling rigs can also be very ‘peaky’ in power requirements. You can go from , not a lot, to, metric ass loads or power needed very quickly. Wind, wave etc don’t really accommodate that need. Batteries or other forms of power storage wont help as that just adds weight, and for the peak loads required it would be a lot of batteries, and semi sub rigs need all the deck loading they can get for fluids , tubulars etc.The cost of all those batteries would out weigh the cost savings of using renewables.
I am not sure that many operators or drilling contractors are ideologically opposed to any source of power , be it green or other wise. Operational demands of reliability , cost and maintainability tend to drive the choice.


Vessels like this…

( ok thats a dramatic picture, its obviously not always like that, Google offshore supply vessel for more pictures)
Will bring out items generally packaged in 10ft or 8ft shipping containers , that are stores on the flat deck at the back and transferred to the rig via crane. Long tubular items will also be stored there and moved over by crane . Fluids will be store in tanks on the boat, the crane will pull over a hose and fluids can be transferred to and from the rig, there can be quite a lot of shuttling of fluids used for drilling and completing different stages of the well. As Karpov mentioned this is just for drilling related supplies. The produced oil is handled in a very different way.

How often do they need to resupply- really depends on the rig, the operation and the location. One reason for moving to drill ships particularly for deepwater operations is that a ship can have a much higher variable deck loading, ie carry more stuff, than a semi submersible rig.